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STORM WATER MANAGEMENT MODEL USER`S MANUAL Version

1. The results of this request will be a Statistics Report form see Figure 2 23 containing four tabbed pages a Summary page an Events page containing a rank ordered listing of each event a Histogram page containing a plot of the occurrence frequency versus event magnitude and a Frequency Plot page that plots event magnitude versus cumulative frequency 30 Statistics System Rainfall E ES Summary Events Histogram Frequency Plot SUMAN AY STATISTICS System Variable Paintfall Lin hr Event Statistic Event Total fin Period of Pecord 01701719958 to O1 O1 2000 Number of Events 13 Event Frequency 076 Minimum Value 010 Maximum Value 350 Mean Value 309 Std Deviation 449 Skepmess Coeff 161 Figure 2 23 Statistical Analysis report The summary page shows that there were a total of 213 rainfall events The Events page shows that the largest rainfall event had a volume of 3 35 inches and occurred over a 24 hour period There were no events that matched the 3 inch 6 hour design storm event used in our previous single event analysis that had produced some internal flooding In fact the status report for this continuous simulation indicates that there were no flooding or surcharge occurrences over the simulation period We have only touched the surface of SWMM s capabilities Some additional features of the program that you will find useful include utilizing additional types
2. aline of text that describes the file can be blank the time step used for all inflow records integer seconds the number of variables stored in the file where the first variable must always be flow rate the name and units of each variable one per line where flow rate is the first variable listed and is always named FLOW the number of nodes with recorded inflow data the name of each node one per line a line of text that provides column headings for the data to follow can be blank for each node at each time step a line with the name of the node the date year month and day separated by spaces the time of day hours minutes and seconds separated by spaces the flow rate followed by the concentration of each quality constituent 145 Time periods with no values at any node can be skipped An excerpt from an RDII routing interface file 1s shown below SWMM 5 Example File 300 1 FLOW CES 2 N1 N2 Node Year Mon Day Hr Min Sec Flow N1 2002 04 0L 00 20 00 0 000000 N2 200 04 OL 00 20 00 0 002549 N1 2002 04 OL 0023 00 0 000000 N2 2004 04 0k DU 237 O0 702002549 146 CHAPTER 12 USING ADD IN TOOLS SWMM 5 has the ability to launch external applications from its graphical user interface that can extend its capabilities This section describes how such tools can be registered and share data with SWMM 5 12 1 What Are Add In Tools Add in tools are third party appli
3. and Value is an attribute value Some examples of condition clauses are NODE N23 DEPTH gt 10 PUMP P45 STATUS OFF SIMULATION TIME 12 45 00 235 The objects and attributes that can appear in a condition clause are as follows Object Attributes Value NODE DEPTH numerical value HEAD numerical value INFLOW numerical value DEPTH numerical value FLOW numerical value ORIFICE SETTING WEIR SETTING decimal hours or hr min sec SIMULATION DATE month day year CLOCKTIME time of day in hr min sec An action clause of a Control Rule can have one of the following formats PUMP id STATUS ON OFF PUMP ORIFICE WEIR OUTLET id SETTING value where the meaning of SETTING depends on the object being controlled for Pumps it is a multiplier applied to the flow computed from the pump curve for Orifices it is the fractional amount that the orifice is fully open for Weirs it is the fractional amount of the original freeboard that exists 1 e weir control is accomplished by moving the crest height up or down for Outlets it is a multiplier applied to the flow computed from the outlet s rating curve Modulated controls are control rules that provide for a continuous degree of control applied to a pump or flow regulator as determined by the value of some controller variable such as water depth at a node or by time The functional relation between the control setting and the controller variable is specified by usin
4. 3 Select OK to accept your selections 124 Graph Options General Horizontal Axis Vertical Axis Legend Series Panel Color Background Color View in 3D L 3D Effect Percent SS Main Title Doa Graph Options General The following options can be set on the General page of the Graph Options dialog box Panel Color Color of the panel that contains the graph Background Color Color of graph s plotting area View in 3D Check if graph should be drawn in 3D 3D Effect Percent Degree to which 3D effect is drawn Main Title Text of graph s main title Font Click to set the font used for the main title 125 Graph Options Axes The Horizontal Axis and Vertical Axis pages of the Graph Options dialog box adjust the way that the axes are drawn on a graph Minimum Sets minimum axis value minimum data value is shown in parentheses Can be left blank Maximum Sets maximum axis value maximum data value is shown in parentheses Can be left blank Increment Sets increment between axis labels Can be left blank Auto Scale If checked then Minimum Maximum and Increment settings are ignored Gridlines Toggles the display of grid lines on and off Axis Title Text of axis title Font Click to select a font for the axis title Graph Options Legend The Legend page of the Graph Options dialog box controls how the legend is displayed on the graph Position Selects where to place the legend Color Sel
5. Fraction transferred to the impervious area The fraction of excess snow depth that is added to snow accumulation on the pack s impervious area Fraction transferred to the pervious area The fraction of excess snow depth that is added to snow accumulation on the pack s pervious area Fraction converted to immediate melt The fraction of excess snow depth that becomes liquid water which runs onto any subcatchment associated with the snow pack 200 Fraction moved to another subcatchment The fraction of excess snow depth which is added to the snow accumulation on some other subcatchment The name of the subcatchment must also be provided C 14 Time Pattern Editor The Time Pattern Editor is invoked when a new time pattern object is created or an existing time pattern is selected for editing The editor contains that following data entry fields Time Pattern Editor Mame Type HOURLY Z Description Multipliers Cancel Help Name Enter the name assigned to the time pattern Type Select the type of time pattern being specified Description You can provide an optional comment or description for the time pattern If more than one line is needed click the Z button to launch a multi line comment editor Multipliers Enter a value for each multiplier The number and meaning of the multipliers changes with the type of time pattern selected MONTHLY One multiplier for each month of the year DAILY One multip
6. Supply the text for a footer that will appear on each page 10 Indicate whether the footer should be printed or not and how its text should be aligned 11 Indicate whether pages should be numbered 12 Click OK to accept your choices Page Setup Margins Headers Footers Header Doo Align C Lett Center Right Enabled Footer gwh 5 Align C Lett Center Right Enabled Cancel Figure 10 2 The Headers Footers page of the Page Setup dialog 136 10 3 Print Preview To preview a printout select File gt gt Print Preview from the Main Menu A Preview form will appear which shows how each page being printed will appear While in preview mode the left mouse button will re center and zoom in on the image and the right mouse button will re center and zoom out 10 4 Printing the Current View To print the contents of the current window being viewed in the SWMM workspace either select File gt gt Print from the Main Menu or click amp on the Standard Toolbar The following views can be printed Study Area Map at the current zoom level Status Report Graphs Time Series Profile and Scatter plots Tabular Reports Statistical Reports 10 5 Copying to the Clipboard or to a File SWMM can copy the text and graphics of the current window being viewed to the Windows clipboard or to a file Views that can be copied in this fashion include the Study Area Map graphs tables
7. pairs Time can be specified either as hours from the start of a simulation or as an absolute date and time of day y For rainfall time series it is only necessary to enter periods with non zero rainfall amounts SWMM interprets the rainfall value as a constant value lasting over the recording interval specified for the rain gage that utilizes the time series For all other types of time series SWMM uses interpolation to estimate values at times that fall in between the recorded values Y For times that fall outside the range of the time series SWMM will use a value of O for rainfall and external inflow time series and either the first or last series value for temperature evaporation and water stage time series 3 3 13 Time Patterns Time Patterns allow external Dry Weather Flow DWF to vary in a periodic fashion They consist of a set of adjustment factors applied as multipliers to a baseline DWF flow rate or pollutant concentration The different types of time patterns include Monthly one multiplier for each month of the year Daily one multiplier for each day of the week Hourly one multiplier for each hour from 12 AM to 11 PM Weekend hourly multipliers for weekend days Each Time Pattern must have a unique name and there is no limit on the number of patterns that can be created Each dry weather inflow either flow or quality can have up to four patterns associated with it one for each type listed above 3 4 Com
8. the conduit Avg Loss Coeff length of the conduit Flap Gate YES if a flap gate exists that prevents backflow through the conduit or NO if no flap gate exists NOTE Conduits and flow regulators orifices weirs and outlets can be offset some distance above the invert of their connecting end nodes There are two different conventions available for specifying the location of these offsets The Depth convention uses the offset distance from the node s invert distance between and Y in the figure on the right The Elevation convention uses the absolute elevation of the offset location the elevation of point in the figure The choice of convention can be made on the General Page of the Simulation Options dialog or on the Node Link Properties page of the Project Defaults dialog Head loss coefficient associated with energy losses along the 167 B 8 B 9 Pump Properties Name User assigned pump name Inlet Node Name of node on the inlet side of the pump Outlet Node Name of node on the outlet side of the pump Description Click the ellipsis button or press Enter to edit an optional description of the pump Ta Optional label used to categorize or classify the pump Curve Name of the Pump Curve which contains the pump s operating data double click to edit the curve Use for an Ideal pump Initial Status Status of the pump ON or OFF at the start of the simulation Startup
9. A SWMM project file is a plain text file that contains all of the data used to describe a study area and the options used to analyze it The file is organized into sections where each section generally corresponds to a particular category of object used by SWMM The contents of the file can be viewed from within SWMM while it is open by selecting Project gt gt Details from the Main Menu An existing project file can be opened by selecting File gt gt Open from the Main Menu and be saved by selecting File gt gt Save or File gt gt Save As Normally a SWMM user would not edit the project file directly since SWMM s graphical user interface can add delete or modify a project s data and control settings However for large projects where data currently reside in other electronic formats such as CAD or GIS files it may be more expeditious to extract data from these sources and save it to a formatted project file before running SWMM The format of the project file is described in detail in Appendix D of this manual After a project file is saved to disk a settings file will automatically be saved with it This file has the same name as the project file except that its extension is ini e g if the project file were named projectl inp then its settings file would have the name project1 ini It contains various settings used by SWMM s graphical user interface such as map display options legend colors and intervals object default values
10. HOTSTART Cli Projects SWMMS testl_ h Add adds a new interface file specification to the list Edit edits the properties of the currently selected interface file Delete deletes the currently selected interface from the project but not from your hard drive 109 When the Add or Edit buttons are clicked an Interface File Selector dialog appears where you can specify the type of interface file whether it should be used or saved and its name The entries on this dialog are as follows Interface File Selector File Type HOTSTART Save File O Use File File Name File Type Select the type of interface file to be specified Use Save Buttons Select whether the named interface file will be used to supply input to a simulation run or whether simulation results will be saved to it File Name Enter the name of the interface file or click the Browse button LEN to select from a standard Windows file selection dialog box 8 2 Starting a Simulation To start a simulation either select Project gt gt Run Simulation from the Main Menu or click a3 on the Standard Toolbar A Run Status window will appear which displays the progress of the simulation 110 Run Status U U Percent Complete 3 4 00 Simulated Time Days U Are Min 07 53 To stop a run before its normal termination click the Stop button on the Run Status window or press the lt Esc gt key Simulation results up until the tim
11. Set to zero to use a standard shaped elliptical pipe as cataloged in the publications mentioned in the footnote below As listed in either the Concrete Pipe Design Manual published by the American Concrete Pipe Association or Modern Sewer Design published by the American Iron and Steel Institute 232 Section Purpose Formats Remarks LOSSES Specifies minor head loss coefficients and flap gates for conduits Conduit Kentry Kexit Kavg Flap Conduit name of conduit Kentry entrance minor head loss coefficient Kexit exit minor head loss coefficient Kavg average minor head loss coefficient across length of conduit Flap YES if conduit has a flap valve that prevents back flow NO otherwise Default is NO Minor losses are only computed for the Dynamic Wave flow routing option see OPTIONS section They are computed as Kv 2g where K minor loss coefficient v velocity and g acceleration of gravity Entrance losses are based on the velocity at the entrance of the conduit exit losses on the exit velocity and average losses on the average velocity Only enter data for conduits that actually have minor losses or flap valves 233 Section Purpose Formats Remarks TRANSECTS Describes the cross section geometry of natural channels or conduits with irregular shapes following the HEC 2 data format NC Nlef x1 Name GR Elev Nleft NEON Nchanl Name Nsta Xleft XLIGNC W iactor
12. The Overview Map as pictured below allows one to see where in terms of the overall system the main Study Area Map is currently focused This zoom area 1s depicted by the rectangular outline displayed on the Overview Map As you drag this rectangle to another position the view within the main map will be redrawn accordingly The Overview Map can be toggled on and off by selecting View gt gt Overview Map from the Main Menu The Overview Map window can also be dragged to any position as well as be re sized 97 7 12 Study Area Map Overview Map EOR Setting Map Display Options The Map Options dialog shown below is used to change the appearance of the Study Area Map There are several ways to invoke it select Tools gt gt Map Display Options from the Main Menu or click the Options button ET on the Standard Toolbar when the Study Area Map window has the focus or right click on any empty portion of the map and select Options from the popup menu that appears The dialog contains a separate page selected from the panel on the left side of the form for each of the following display option categories Subcatchments controls fill style symbol size and outline thickness of subcatchment areas Nodes controls size of nodes and making size be proportional to value Links controls thickness of links and making thickness be proportional to value Labels turns display of map labels on off Annotation displays or hides
13. height of WEIR divider ft or m discharge coefficient for WEIR divider depth from ground to invert elevation ft or m default is 0 water depth at start of simulation ft or m default is 0 maximum additional head above ground elevation that node can sustain under surcharge conditions ft or m default is 0 area subjected to surface ponding once water depth exceeds Ymax ft2 or m2 default is 0 226 Section Purpose Format Remarks STORAGE Identifies each storage node of the drainage system Storage nodes can have any shape as specified by a surface area versus water depth relation Name Name Name Elev Ymax YO Acurve Al A2 AO Apond Fevap Elev Ymax YO TABULAR lt Acurve Apond Fevap Elev Ymax YO FUNCTIONAL Al A2 AO Apond Fevap name assigned to storage node invert elevation ft or m maximum water depth possible ft or m water depth at start of simulation ft or m name of curve in CURVES section with surface area ft2 or m2 as a function of depth ft or m for TABULAR geometry coefficient of FUNCTIONAL relation between surface area and depth exponenet of FUNCTIONAL relation between surface area and depth constant of FUNCTIONAL relation between surface area and depth surface area subjected to ponding once water depth exceeds Ymax ft2 or m2 default 1s 0 fraction of potential evaporation from surface realized default is 0 Al A2 and AO are used in the foll
14. 2 Select View gt gt Query or click on the Map Toolbar 3 Fill in the following information in the Query dialog that appears Select whether to search for Subcatchments Nodes or Links Select a parameter to query Select the appropriate operator Above Below or Equals Enter a value to compare against 4 Click the Go button The number of objects that meet the criterion will be displayed in the Query dialog and each such object will be highlighted on the Study Area Map 5 As a new time period is selected in the Browser the query results are automatically updated 6 You can submit another query using the dialog box or close it by clicking the button in the upper right corner 95 Study Area Map Find Nodes MMI Flooding Above Go 1 items found After the Query box is closed the map will revert back to its original display 7 10 Using the Map Legends Map Legends associate a color with a range of values for the current theme being viewed Separate legends exist for Subcatchments Nodes and Links A Date Time Legend is also available for displaying the date and clock time of the simulation period being viewed on the map To display or hide a map legend 1 Select View gt gt Legends from the Main Menu or right click on the map and select Legends from the pop up menu that appears 2 Click on the type of legend whose display should be toggled on or off A visible legend can also be hidden by do
15. 3 4 6 Surface Ponding Normally in flow routing when the flow into a junction exceeds the capacity of the system to transport it further downstream the excess volume overflows the system and is lost An option exists to have instead the excess volume be stored atop the junction in a ponded fashion and be reintroduced into the system as capacity permits Under Steady and Kinematic Wave flow routing the ponded water is stored simply as an excess volume For Dynamic Wave routing which is influenced by the water depths maintained at nodes the excess volume is assumed to pond over the node with a constant surface area This amount of surface area is an input parameter supplied for the junction Alternatively the user may wish to represent the surface overflow system explicitly In open channel systems this can include road overflows at bridges or culvert crossings as well as additional floodplain storage areas In closed conduit systems surface overflows may be conveyed down streets alleys or other surface routes to the next available stormwater inlet or open channel Overflows may also be impounded in surface depressions such as parking lots back yards or other areas 3 4 7 Water Quality Routing Water quality routing within conduit links assumes that the conduit behaves as a continuously stirred tank reactor CSTR Although a plug flow reactor assumption might be more realistic the differences will be small if the travel time through the c
16. 7 the properties of data objects that can appear on the Study Area Map It is invoked when one of these EE 117 objects is selected either on the Study Area Map or in the Data Browser and double clicked or when the Data Outlet Node 18 Browser s Edit button 1s clicked Description a Tag Key features of the Property Editor include F ape Length 400 Roughness 0 01 The Editor is a grid with two columns one for the property s name and the other for its value The columns can be re sized by re sizing the header at the top of the Editor with the mouse Inlet Offset U 44 Click to edit the conduit s cross section geometry A hint area is displayed at the bottom of the Editor with an expanded description of the property being edited The size of this area can be adjusted by dragging the splitter bar located just above it The Editor window can be moved and re sized via the normal Windows operations Depending on the property the value field can be one of the following a text box in which you enter a value 34 dropdown combo box from which you select a value from a list of choices 4 dropdown combo box in which you can enter a value or select from a list of choices an ellipsis button which you click to bring up a specialized editor The property field in the Editor that currently has the focus will be highlighted with a white background Both the mouse and the Up and Down arrow keys on the keyboard
17. Formats DIMENSIONS X1 Y1 X2 Y2 UNITS FEET METERS DEGREES NONE Remarks X1 lower left X coordinate of full map extent Yl lower left Y coordinate of full map extent X2 upper right X coordinate of full map extent YZ upper right Y coordinate of full map extent Section COORDINATES Purpose Assigns X Y coordinates to drainage system nodes Format Node Xcoord Ycoord Remarks Node name of node Xcoord horizontal coordinate relative to origin in lower left of map Ycoord vertical coordinate relative to origin in lower left of map Section VERTICES Purpose Assigns X Y coordinates to interior vertex points of curved drainage system links Format Link Xcoord Ycoord Remarks Link name of link Xcoord horizontal coordinate of vertex relative to origin in lower left of map Ycoord vertical coordinate of vertex relative to origin in lower left of map Include a separate line for each interior vertex of the link ordered from the inlet node to the outlet node Straight line links have no interior vertices and therefore are not listed in this section 251 Section POLYGONS Purpose Assigns X Y coordinates to vertex points of polygons that define a subcatchment boundary Format Subcat Xcoord Ycoord Remarks Subcat name of subcatchment Xcoord horizontal coordinate of vertex relative to origin in lower left of map Ycoord vertical coordinate of vertex relative to origin in lower left of map Include a separate line for each vert
18. Full Extent p Measures a length or area on the map 64 Object Toolbar The Object Toolbar contains buttons for adding objects to the study area map Adds a rain gage to the map Adds a subcatchment to the map Adds a junction node to the map Adds an outfall node to the map Adds a flow divider node to the map Adds a storage unit node to the map Adds a conduit link to the map Adds a pump link to the map Adds an orifice link to the map Adds a weir link to the map Adds an outlet link to the map 2380883110730 Adds a label to the map 4 4 Status Bar The Status Bar appears at the bottom of SWMM s Main Window and is divided into six sections Auto Length OF Offsets Depth Flow Units CFS oom Level 100 A 711 500 7 584 ft Auto Length Indicates whether the automatic computation of conduit lengths and subcatchment areas is turned on or off The setting can be changed by clicking the drop down arrow Offsets Indicates whether the positions of links above the invert of their connecting nodes are expressed as a Depth above the node invert or as the Elevation of the offset Click the drop down arrow to change this option If changed a dialog box will appear asking if all existing offsets in the current project should be changed or not 1 e convert Depth offsets to Elevation offsets or Elevation offsets to Depth offsets depending on the option selected Flow Units Displays the current flow units
19. It updates the state of the snow packs associated with each subcatchment by accounting for snow accumulation snow 99 redistribution by areal depletion and removal operations and snow melt via heat budget accounting Any snowmelt coming off the pack is treated as an additional rainfall input onto the subcatchment At each runoff time step the following computations are made 1 Air temperature and melt coefficients are updated according to the calendar date 2 Any precipitation that falls as snow is added to the snow pack 3 Any excess snow depth on the plowable area of the pack is redistributed according to the removal parameters established for the pack 4 Areal coverages of snow on the impervious and pervious areas of the pack are reduced according to the Areal Depletion Curves defined for the study area 5 The amount of snow in the pack that melts to liquid water 1s found using a a heat budget equation for periods with rainfall where melt rate increases with increasing air temperature wind speed and rainfall intensity b a degree day equation for periods with no rainfall where melt rate equals the product of a melt coefficient and the difference between the air temperature and the pack s base melt temperature 6 Ifno melting occurs the pack temperature is adjusted up or down based on the product of the difference between current and past air temperatures and an adjusted melt coefficient If melting occurs the temper
20. Robert Shubinsky Finally we wish to thank Wayne Huber Thomas Barnwell US EPA Richard Field US EPA Harry Torno US EPA retired and William James University of Guelph for their continuing efforts to support and maintain the program over the past several decades CHAPTER 1 INTRODUCTION 1 1 LZ 1 3 1 4 1 5 1 6 CHAPTER 2 QUICK START TUTORIAL 24 22 24 2 4 2D 2 6 27 CHAPTER 3 SWMM S CONCEPTUAL MODEL 3 1 3 2 3 3 3 4 CHAPTER 4 SWMM S MAIN WINDOW 4 1 CONTENTS WW TESS WMM titi Modeling Capabilities aneao Typical Applications of SW MM Installing EPA SWMM snstastin cai Stepsin Usina SWMM Lada About This MA a e do en ESO Example study ATA A Project ED A cldeal anion tonte DFA WS OCC US sas noticed teta iris settino Object PLO aT Running a Simulation 0 ccccccecseesssesecccecetenesenesececacateassenenccesenedanees Simule Water T ATT Running a Continuous Simulation sees eee eee eee eee TOO a A ES Ker UEC A CN NoD VBU OBI CCtS ara a aa cali Computational Methods sss TIE ASS A 4 2 IW MEU H 60 4 3 TOOD ac earners ret te E 63 4 4 SES Din 65 4 5 Sy AC a IV TTT 66 4 6 Ba TB ON TTT 67 4 7 MaD BION SET conira e is 67 4 8 PHOS Uy ION TT 69 4 9 Sene POCA TERT CNC CS siete aries alae a 70 CHAPTER 5 WORKING WITH PROJECTS ssssssssss essen ee neeaaea enne 73 5 1 Creag a NeW PTO CO O i 73 Z2 Opening an Existine Proje iD aA 73 53 SY RATA RSA
21. Snow Pack Name of snow pack parameter set if any assigned to the subcatchment Initial Buildup Click the ellipsis button or press Enter to specify initial quantities of pollutant buildup over the subcatchment Land Uses Click the ellipsis button or press Enter to assign land uses to the subcatchment Total length of curbs in the subcatchment any length units Used Curb Length only when pollutant buildup is normalized to curb length B 3 Junction Properties Name User assigned junction name junction name X Coordinate Horizontal location of the junction on the Study Area Map If left blank then the junction will not appear on the map Y Coordinate Vertical location of the junction on the Study Area Map If left blank then the junction will not appear on the map Description Click the ellipsis button or press Enter to edit an optional y h nn of the junction Tag Optional label used to categorize or Optional label used to categorize or classify the junction the junction a Click the ellipsis button or press Enter to assign external direct dry weather or RDII inflows to the junction Treatment Click the ellipsis button or press Enter to edit a set of treatment functions for pollutants entering the node Invert El Invert elevation of the junction feet or meters Max Depth Maximum depth of junction 1 e from ground surface to invert feet or meters If zero then th
22. The properties of an object displayed on the Study Area Map can be copied and pasted into another object from the same category To copy the properties of an object to SWMM s internal clipboard 1 Right click the object on the map 2 Select Copy from the pop up menu that appears To paste copied properties into an object 1 Right click the object on the map 2 Select Paste from the pop up menu that appears Only data that can be shared between objects of the same type can be copied and pasted Properties not copied include the object s name coordinates end nodes for links Tag property 85 and any descriptive comment associated with the object For Map Labels only font properties are copied and pasted 6 7 Shaping and Reversing Links Links can be drawn as polylines containing any number of straight line segments that define the alignment or curvature of the link Once a link has been drawn on the map interior points that define these line segments can be added deleted and moved To edit the interior points of a link 1 Select the link to edit on the map and put the map in Vertex Selection mode either by clicking on the Map Toolbar selecting Edit gt gt Select Vertex from the Main Menu or right clicking on the link and selecting Vertices from the popup menu 2 The mouse pointer will change shape to an arrow tip and any existing vertex points on the link will be displayed as small open squares The currently sele
23. and calibration file information Users should not edit this file A SWMM project will still load and run even if the settings file is missing 11 2 Report and Output Files The report file is a plain text file created after every SWMM run that contains a status report on the results of a run It can be viewed by selecting Report gt gt Status from the main menu If the run was unsuccessful 1t will contain a list of error messages For a successful run 1t will contain the mass continuity errors for runoff quantity and quality as well as for flow and water quality routing summary results tables for all drainage system nodes and links and information about the time step size and iterations required when Dynamic Wave routing analyses are performed The output file is a binary file that contains the numerical results from a successful SWMM run This file is used by SWMM s user interface to interactively create time series plots and tables profile plots and statistical analyses of a simulation s results 139 Whenever a successfully run project is either saved or closed the report and output files are saved with the same name as the project file but with extensions of rpt and out This will happen automatically if the program preference Prompt to Save Results is turned off see Section 4 9 Otherwise the user is asked if the current results should be saved or not If results are saved then the next time the project is opened
24. depending on the hydraulic gradient that exists The same aquifer object can be shared by several subcatchments Aquifers are only required in models that need to explicitly account for the exchange of groundwater with the drainage system or to establish baseflow and recession curves in natural channels and non urban systems Aquifers are represented using two zones an un saturated zone and a saturated zone Their behavior is characterized using such parameters as soil porosity hydraulic conductivity evapotranspiration depth bottom elevation and loss rate to deep groundwater In addition the initial water table elevation and initial moisture content of the unsaturated zone must be supplied Aquifers are connected to subcatchments and to drainage system nodes as defined in a subcatchment s Groundwater Flow property This property also contains parameters that govern the rate of groundwater flow between the aquifer s saturated zone and the drainage system node 3 3 4 Unit Hydrographs Unit Hydrographs UHs estimate rainfall dependent infiltration inflow RDII into a sewer system A UH set contains up to three such hydrographs one for a short term response one for an intermediate term response and one for a long term response A UH group can have up to 12 UH sets one for each month of the year Each UH group is considered as a separate object by SWMM and is assigned its own unique name along with the name of the rain gage that supplies r
25. map s background with 7 13 Exporting the Map The full extent view of the study area map can be saved to file using either Autodesk s DXF Drawing Exchange Format format the Windows enhanced metafile EMF format EPA SWMM s own ASCII text map format The DXF format is readable by many Computer Aided Design CAD programs Metafiles can be inserted into word processing documents and loaded into drawing programs for re scaling and editing Both formats are vector based and will not lose resolution when they are displayed at different scales To export the map to a DXF metafile or text file 1 Select File gt gt Export gt gt Map 2 In the Map Export dialog that appears select the format that you want the map saved in Map Export Export Map To Test File map Enhanced Metafile emf Drawing Exchange File def Draw Junchons 4s Open circles Filled circles Filled squares 102 If you select DXF format you have a choice of how nodes will be represented in the DXF file They can be drawn as filled circles as open circles or as filled squares Not all DXF readers can recognize the format used in the DXF file to draw a filled circle Also note that map annotation such as node and link ID labels will not be exported but map label objects will be After choosing a format click OK and enter a name for the file in the Save As dialog that appears 103 This page inte
26. 00 Report Time Step 15 00 KKKKKKKKKKKKKKKKKKKKKKKKEKK Volume Depth Runoff Quantity Continuity acre feet inches KKEKKKKKKKKKKKKKKKKKKKKKKKK Total Precipitation Evaporation Loss Infiltration Loss Surface Runoff Final Surface Storage Q Continuity Error KKKKKKKKKKKKKKKKKKKKKKKKEKK Volume Flow Routing Continuity Mgallons K ARA AR Dry Weather Inflow Wet Weather Inflow Groundwater Inflow RDII Inflow External Inflow Internal Flooding External Outflow Evaporation Loss Initial Stored Volume Final Stored Volume Q Continuity Error OO 0 10 Oo Oo PO O O OO OO 0 0 Figure 2 10 Portion of the Status Report for initial simulation run In SWMM flooding will occur whenever the water surface at a node exceeds the maximum defined depth or if more flow volume enters a node than can be stored or released during a given time step Normally such water will be lost from the system The option also exists to have this water pond atop the node and be re introduced into the drainage system when capacity exists to do so 18 Viewing Results on the Map Simulation results as well as some design parameters such as subcatchment area node invert elevation and link maximum depth can be viewed in color coded fashion on the study area map To view a particular variable in this fashion La des Select the Map page of the Browser panel Select the variables to view for Subcatchments No
27. 1 VIC WIT As Status AIRC OM THT 115 9 2 Variables Phat Can Be Vie lios 118 9 3 Viewme Results n the Maps io iii 118 9 4 Viewine Results with a E a dd 119 9 5 Customizing a Graph s Appearance eee ee e ee 124 vii 9 6 Viewine Results with a Table ad N 128 9 7 VIEWING A Statistics REPO di it 130 CHAPTER 10 PRINTING AND COPYING ss sss ss ss ss sss sss ss esse eee se ennenen ennenen 135 tO as ee ee A ee enae 135 1072 Settune the Pace v TTT 136 103 AS ere re ora ov eA Oe eR I ner TS ee ee eer eee 137 10 Printine the Current VEW a n e 137 10 5 Copying to the Clipboard or to SLT 137 CHAPTER 11 FILES USED BY SWMM ssss ss sss sss s sse se eee ee nenen eee ee 139 TEE ELO AMES e do 139 12 Report and Output lesa 139 MLS Ramales did 140 R Cima Ple ls O eee 140 LS Calbraton Piles A 141 LO Time Scenes Ple 142 LES A II acca dee tak eo dati 143 CHAPTER 12 USING ADD IN TOOLS oonncccnccccnnnncnnnncnnncnonanecnnnncnnnnenannnonanrenannenananos 147 22h WhatAre Addalin TOONS ur a 147 12 2 Contouring Aad iTO sissies a 148 APPENDIX A USEFUL TABLES cuina 153 A l Unitsot Measurement ao 153 A 2 KTS Kee ee T 154 A 3 NRCS Hydrologic Soil Group Definitions sese ee eee eee 155 AA E 156 A 5 DEPTO S10 ba TTT 157 viii A 6 Manning siti Overland FloW iia 157 A 7 Manning S n Closed Conduits is 158 A 8 Mantas gt Open COMO A a E si 159 A 9 Water Quality Characteristics of Urban Runa sss 159 APPENDIX B VI
28. A backdrop drawing such as a street or topographic map can be placed behind the network map for reference The map can be zoomed to any scale and panned from one position to another Nodes and links can be drawn at different sizes flow direction arrows added and object symbols ID labels and numerical property values displayed 66 The map can be printed copied onto the Windows clipboard or exported as a DXF file or Windows metafile 4 6 Data Browser The Data Browser panel shown below appears when the Data tab on the left panel of the SWMM workspace is selected It provides access to all of the data objects in a project The vertical sizes of the list boxes in the browser can be adjusted by using the splitter bar located just below the upper list box The width of the Data Browser panel can be adjusted by using the splitter bar located along its right edge Map The upper list box displays the various categories of data 0 objects available to a SWMM project The lower list box lists the name of each individual object of the currently selected data category Hydrology B Hydraulics H Nodes B Links Conduits Z The buttons between the two list boxes of the Data Browser Pumps are used as follows Drificez adds a new object Wells deletes the selected object gt Z edits the selected object T moves the selected object up one position moves the selected object down one position sorts the objects in ascending or
29. Area with No Depression Storage Infiltration Method The default properties of a subcatchment can be modified later by using the Property Editor 75 Default Node Link Properties The Nodes Links page of the Project Defaults dialog sets default property values for newly created nodes and links These properties include Node Invert Elevation Node Maximum Depth Node Ponded Area Conduit Length Conduit Shape and Size Conduit Roughness Flow Units Link Offsets Convention Routing Method Force Main Equation The defaults automatically assigned to individual objects can be changed by using the object s Property Editor The choice of Flow Units and Link Offsets Convention can be changed directly on the main window Status Bar 5 5 Measurement Units SWMM can use either US units or SI metric units The choice of flow units determines what unit system is used for all other quantities selecting CFS cubic feet per second GPM gallons per minutes or MGD million gallons per day for flow units implies that US unitswill be used throughout selecting CMS cubic meters per second LPS liters per second or MLD million liters per day as flow units implies that SI unitswill be used throughout Flow units can be selected directly on the main window s Status Bar or by setting a project s default values In the latter case the selection can be saved so that all new future projects will automatically use those units y
30. Bl ea OCE Sane ee DO O eee Rear eT ao enn ree etry me Mere Oe mr enon eee Rove en oneee ener ee emt 73 5 4 Settino PEO Ec r DET S E 74 5 5 A a a 76 5 6 EA T7 5 7 Cambra IAA ask sac E A tae H 77 5 8 Vew Al Project Dala tutti pa 79 CHAPTER 6 WORKING WITH OQOBJEC TS sss sss ss sss sese se seene nenen ennenen 81 6 1 OB Se py col S err eee One ne ERT Eee Rie en eer ias 81 6 2 AMO O oo aiii 81 6 3 Sclectin and Movie OD loci 83 6 4 Edita ODE ii 84 6 5 Cony erune An TEI bile aaa 85 6 6 Copyineand Pastine RL 85 6 7 Shape and Reversino LK HT 86 6 8 Skapin e a UDe MITC TT 86 vi 6 9 Peline A OD ds 86 6 10 Editing or Deleting a Group Of ObjectS oooooonnnnnccccnnnnncnoncnnnononnnnnannnnncnnnnnnnnnnnnnnnnnnonnnnnos 87 CHAPTER 7 WORKING WITH THE MAP sss ssss sss sss sss sss sese enen 89 7 1 CIE CUS AMI Ap LTE 89 GD Setting Me Map KTT 89 7 3 Wiltz a Backdrop TT 90 7 4 WE AS Uri Distance oros 93 7 5 ZOO TNS Map TTT 93 7 6 RST ET L by 0 Merman emia Oe aren ter ew er A en ern POP 94 7 1 Viewme at Pull S 94 7 8 Par a OD TTT 95 7 9 SUOM Map QUE did 95 TAO Usme the Map E Te aia 96 Tall Usm Me Overview Maps aid 97 A12 Seuns Map Display OPUS le ido 98 TAO EXpPortins tHe MAP A i 102 CHAPTER 8 RUNNING A SIMULATION 00 0 sss eee e eens essen nenen nee 105 8 1 Setn SUN HON e eE TTT 105 8 2 Station tio ral dedica 110 8 3 Proubleshootna TK SUNG aio 111 CHAPTER 9 VIEWING RESULTS ccs ss css cesses senenn nenen 115 9
31. Depth Startup Depth Depth at inlet node when pump turns on feet or meters Depth at inlet node when pump turns on feet or meters Shutoff Depth Depth at inlet node when pump shuts off feet or meters Depth at inlet node when pump shuts off feet or meters Orifice Properties Name User assigned orifice name Inlet Node Name of node on the inlet side of the orifice Outlet Node Name of node on the outlet side of the orifice Description Click the ellipsis button or press Enter to edit an optional description of the orifice Tag Optional label used to categorize or classify the orifice Type Type of orifice SIDE or BOTTOM Shape Orifice shape CIRCULAR or RECT_CLOSED Height Height of orifice opening when fully open feet or meters Corresponds to the diameter of a circular orifice or the height of a O N orifice Width Width of rectangular orifice when Width of rectangular orifice when fully opened feet or meters opened feet or meters Inlet Offset Depth or elevation of bottom of orifice above invert of inlet node feet or meters see note below table of Conduit Properties Discharge Coeff Discharge Coeff Discharge coefficient unitless A typical value is 0 65 Discharge coefficient unitless A typical value is 0 65 Flap Gate YES if a flap gate exists which prevents backflow through the orifice or NO if no flap gate exists Time to Open The time it ta
32. Format Name Nodel Node2 Offset TABULAR OQcurve Flap Name Nodel Node2 Offset FUNCTIONAL Cl C2 Flap Remarks Name name assigned to outlet link Nodel name of node on inlet end of link Node2 name of node on outflow end of link Offset amount that the outlet is offset above the invert of inlet node ft or m expressed as either a depth or as an elevation depending on the LINK_OFFSETS option setting Ocurve name of rating curve listed in CURVES section that describes outflow rate flow units as a function of head ft or m across the outlet for a TABULAR outlet Gi CZ coefficient and exponent respectively of power function that relates outflow Q to head across the link H for a FUNCTIONAL outlet 1 e Q C1 H Flap YES if flap gate present to prevent reverse flow NO if not default is NO Section XSECTIONS Purpose Provides cross section geometric data for conduit and regulator links of the drainage system Formats Link Shape Geoml Geom2 Geom3 Geom4 Barrels Link CUSTOM Geoml Curve Barrels Link IRREGULAR Tsect Remarks Link name of the conduit orifice or weir Shape cross section shape see Table D 1 below for available shapes Geoml full height of the cross section ft or m Geom2 Geom3 Geom4 auxiliary parameters width side slopes etc as listed in Table D 1 Barrels number of barrels 1 e number of parallel pipes of equal size slope and roughness associated with a conduit defau
33. Report will appear describing what errors occurred Upon successfully completing a run there are numerous ways in which to view the results of the simulation We will illustrate just a few here Viewing the Status Report The Status Report contains useful summary information about the results of a simulation run To view the report select Report gt gt Status A portion of the report for the system just analyzed is shown in Figure 2 10 The full report indicates the following The quality of the simulation is quite good with negligible mass balance continuity errors for both runoff and routing 0 23 and 0 04 respectively if all data were entered correctly 17 Of the 3 inches of rain that fell on the study area 1 75 infiltrated into the ground and essentially the remainder became runoff The Node Flooding Summary table not shown in Figure 2 11 indicates there was internal flooding in the system at node J2 The Conduit Surcharge Summary table also not shown in Figure 2 11 shows that Conduit C2 just downstream of node J2 was surcharged and therefore appears to be slightly undersized EPA STORM WATER MANAGEMENT MODEL VERSION 5 0 Tutorial Example KKKKKKKKKKKKKKKK Analysis Options KKEKKKKKKKKKKKKKK Flow Units Infiltration Method GREEN _AMPT Flow Routing Method Starting Date JUN 27 2002 00 00 00 Ending Date JUN 27 2002 12 00 00 Wet Time Step H hes eg 06 Dry Time Step 2 00 00 Routing Time Step 01
34. Select the object on the map or from the Data Browser 2 Either click the button on the Data Browser or press the lt Delete gt key on the keyboard or right click the object on the map and select Delete from the pop up menu that appears 86 Y You can require that all deletions be confirmed before they take effect See the General Preferences page of the Program Preferences dialog box described in Section 4 9 6 10 Editing or Deleting a Group of Objects A group of objects located within an irregular region of the Study Area Map can have a common property edited or be deleted all together To select such a group of objects 1 Choose Edit gt gt Select Region from the Main Menu or click LZ on the Map Toolbar 2 Draw a polygon around the region of interest on the map by clicking the left mouse button at each successive vertex of the polygon 3 Close the polygon by clicking the right button or by pressing the lt Enter gt key cancel the selection by pressing the lt Esc gt key To select all objects in the project whether in view or not select Edit gt gt Select All from the Main Menu Once a group of objects has been selected you can edit a common property shared among them 1 Select Edit gt gt Group Edit from the Main Menu 2 Use the Group Editor dialog that appears to select a property and specify its new value The Group Editor dialog shown below is used to modify a property for a selected group of objects T
35. Shows a detailed listing of all project data Edits a project s default properties Registers files containing calibration data with the project Runs a simulation The Report menu contains commands used to report analysis results in different formats Command Status Graph Table Statistics Customize Tools Menu Description Displays a status report for the most recent simulation run Displays simulation results in graphical form Displays simulation results in tabular form Displays a statistical analysis of simulation results Customizes the display style of the currently active graph The Tools menu contains commands used to configure program preferences study area map display options and external add in tools Command Program Preferences Map Display Options Configure Tools Description Sets program preferences such as font size confirm deletions number of decimal places displayed etc Sets appearance options for the Map such as object size annotation flow direction arrows and back ground color Adds deletes or modifies add in tools 62 Window Menu The Window Menu contains commands for arranging and selecting windows within the SWMM workspace Command Description Cascade Arranges windows in cascaded style with the study area map filling the entire display area Tile Minimizes the study area map and tiles the remaining windows vertically in the display area Close All Closes all open win
36. TITLE Example SWMM Project OPTIONS FLOW_UNITS CFS INFILTRATION GREEN_AMPT FLOW_ROUTING KINWAVE START_DATE 8 6 2002 START_TIME 10 00 END_TIME 18 00 WET_STEP 00 15 00 DRY_STEP 01 00 00 ROUTING_STEP 00 05 00 RAINGAGES Name Format Interval SCF DataSource SourceName 0 O a a NB ag A he Eo NN E we ee re GAGE1 INTENSITY 0 15 1 0 TIMESERIES SERIES1 EVAPORATION CONSTANT 0 02 SUBCATCHMENTS Name Raingage Outlet Area Imperv Width Slope AREA1 GAGE1 NODE1 2 80 0 SOMO Ls AREA2 GAGE1 NODE2 2 19 50 T T0 SUBAREAS S5ubcatch N_Imp N_Perv S_Imp S_Perv ZER RouteTo AREAL E 0 02 0 02 Ol 20 0 OUTLET AREA2 OZ 0 02 Os 02 0 1 Zee OUTLET INFILTRATION Subcatch Suction Conduct InitDef Name Elev DIVIDERS Name Elev Link Type Parameters NODES FeO Ce CUTOFF 15 0 Figure D 1 Example SWMM project file continued on next page 211 CONDUITS Name Nodel Node2 Length N Z1 Z2 00 Cl NODE NODE 3 800 0501 0 0 0 GZ NODE2 NODE 4 800 Or Od U U U C3 NODE 3 NODES 400 OPRIM U U U C4 NODE4 NODES 400 O DL 0 0 0 CS NODES NODE 6 600 OO 0 U U C6 NODES NODE 7 400 Oog 0 0 U XSEGT TONS RE eH Type G1 G2 G3 G4 C1 RECT_OPEN 0 5 1 U U C2 RECT_OPEN 0 5 il U U ES CIRCULAR t0 U U U C4 RECT OFEN Lg Lag 0 U Co PARABOLIC Le 2 0 U U C6 PARABOLIC ES 220 U U POLLUTANTS Name Units Cppt Cow Cii Kd Show CoPollut Gorract TSS MG L 0 U U U Lead UG L U U U U NO TSS Q420 LANDUSE
37. The units of previously entered data are not automatically adjusted if the unit system is changed 76 5 6 Link Offset Conventions Conduits and flow regulators orifices weirs and outlets can be offset some distance above the invert of their connecting end nodes as depicted below There are two different conventions available for specifying the location of these offsets The Depth convention uses the offset distance from the node s invert distance between and in the figure above The Elevation convention uses the absolute elevation of the offset location the elevation of point in the figure The choice of convention can be made on the Status Bar of SWMM s main window or on the Node Link Properties page of the Project Defaults dialog When this convention is changed a dialog will appear giving one the option to automatically re calculate all existing link offsets in the current project using the newly selected convention 5 7 Calibration Data SWMM can compare the results of a simulation with measured field data in its Time Series Plots which are discussed in section 9 4 Before SWMM can use such calibration data they must be entered into a specially formatted text file and registered with the project Calibration Files Calibration Files contain measurements of a single parameter at one or more locations that can be compared with simulated values in Time Series Plots Separate files can be used for each of the following
38. YES if all rainfall data and runoff calculations should be ignored In this case SWMM only performs flow and pollutant routing based on user supplied direct and dry weather inflows The default is NO ALLOW_PONDING determines whether excess water is allowed to collect atop nodes and be re introduced into the system as conditions permit The default is NO ponding In order for ponding to actually occur at a particular node a non zero value for its Ponded Area attribute must be used SKIP_STEADY_STATE should be set to YES if flow routing computations should be skipped during steady state periods of a simulation during which the last set of computed flows will be used A time step is considered to be in steady state if there has been no significant change in external inflows storage volumes and either node water depths for dynamic wave routing or conduit flows for other forms of routing The default for this option is NO START DATE is the date when the simulation begins If not supplied a date of 1 1 2002 is used START TIME is the time of day on the starting date when the simulation begins The default is 12 midnight 0 00 00 END DATE is the date when the simulation is to end The default is the start date END_TIME is the time of day on the ending date when the simulation will end The default is 24 00 00 REPORT_START_DATE is the date when reporting of results is to begin The default is the simulation start date REPORT_START
39. and reports To copy the current view to the clipboard or to file 1 If the current view is a table select the cells of the table to copy by dragging the mouse over them or copy the entire table by selecting Edit gt gt Select All from the Main Menu 2 Select Edit gt gt Copy To from the Main Menu or click the button on the Standard Toolbar 3 Select choices from the Copy dialog see Figure 10 3 that appears and click the OK button 4 If copying to file enter the name of the file in the Save As dialog that appears and click OK Use the Copy dialog as follows to define how you want your data copied and to where 1 Select a destination for the material being copied Clipboard or File 2 Select a format to copy in Bitmap graphics only Metafile graphics only Data text selected cells in a table or data used to construct a graph 3 Click OK to accept your selections or Cancel to cancel the copy request 137 Copy Graph Copy To Copy As 2 Bitmap L 7 Metafile e Clipboard O File Data Text Figure 10 3 Example of the Copy dialog 138 CHAPTER 11 FILES USED BY SWMM This section describes the various files that SWMM can utilize They include the project file the report and output files rainfall files the climate file calibration data files time series files and interface files The only file required to run SWMM is the project file the others are optional 11 1 Project Files
40. as the pollutant EMC as the function type and enter 100 for the coefficient Fill the other fields with 0 Click the OK button to accept your entries Now do the same for the Undeveloped land use category except use a maximum buildup of 25 a buildup rate constant of 0 5 a buildup power of 1 and a washoff EMC of 50 Land Use Editor General Buildup Wwashott Pollutant TSS Property Value Function Max Buildup Rate Constant Powert5 at Constant MNormalizer Buildup funcion POW power E amp P exponential 547 saturation Figure 2 19 Defining a TSS buildup function for Residential land use The final step in our water quality example is to assign a mixture of land uses to each subcatchment area 1 2 3 Select subcatchment S7 into the Property Editor Select the Land Uses property and click the ellipsis button or press Enter In the Land Use Assignment dialog that appears enter 75 for the Residential and 25 for the Undeveloped see Figure 2 20 Then click the OK button to close the dialog Repeat the same three steps for subcatchment S2 Repeat the same for subcatchment S3 except assign the land uses as 25 Residential and 75 Undeveloped 27 Land Use Assignment Land Use 6 of Area Residential 5 Undeveloped 25 Figure 2 20 Land Use Assignment dialog Before we simulate the runoff quantities of TSS and Lead from our study area an initial buildup of TSS should be defin
41. buildup properties are being edited Function The type of buildup function to use for the pollutant The choices are NONE for no buildup POW for power function buildup EXP for exponential function buildup and SAT for saturation function buildup See the discussion of Pollutant Buildup in Section 3 3 9 for explanations of these different functions Select NONE if no buildup occurs Max Buildup The maximum buildup that can occur expressed as Ibs or kg of the pollutant per unit of the normalizer variable see below This is the same as the C1 coefficient used in the buildup formulas discussed in Section 3 3 9 Rate Constant The time constant that governs the rate of pollutant buildup This is the C2 coefficient in the Power and Exponential buildup formulas discussed in Section 3 3 9 For Power buildup its units are mass days raised to a power while for Exponential buildup its units are l days Power Sat Constant The exponent C3 used in the Power buildup formula or the half saturation constant C2 used in the Saturation buildup formula discussed in Section 3 3 9 For the latter case its units are days Normalizer The variable to which buildup is normalized on a per unit basis The choices are either land area in acres or hectares or curb length Any units of measure can be used for curb length as long as they remain the same for all subcatchments in the project 194 When there are multiple pollutants the user must select ea
42. can be used to move between property fields To begin editing the property with the focus either begin typing a value or hit the Enter key 69 To have the program accept edits made in a property field either press the Enter key or move to another property To cancel the edits press the Esc key The Property Editor can be hidden by clicking the button in the upper right corner of its title bar 4 9 Setting Program Preferences Program preferences allow one to customize certain program features To set program preferences select Program Preferences from the Tools menu A Preferences dialog form will appear containing two tabbed pages one for General Preferences and one for Number Formats Preferences H et General Preferences Number Formats Bold Fonts Large Fonts Blinking Map Highlighter Flyover Map Labeling 21 Confirm Deletions Automatic Backup File Report Elapsed Time by Default Prompt to Save Results Clear File List Temporary Directory Oo 70 General Preferences The following preferences can be set on the General Preferences page of the Preferences dialog Preference Description Bold Fonts Check to use bold fonts in all windows Large Fonts Check to use large size fonts in all windows Blinking Map Highlighter Check to make the selected object on the study area map blink on and off Flyover Map Labeling Check to display the ID label and current theme value in a hint style b
43. click Note how the outfall was automatically given the name Qur At this point your map should look something like that shown in Figure 2 4 Figure 2 4 Subcatchments and nodes for example study area Now we will add the storm sewer conduits that connect our drainage system nodes to one another You must have created a link s end nodes as described previously before you can create the link We will begin with conduit C which connects junction J to J2 1 Click the button on the Object Toolbar The mouse cursor changes shape to a crosshair 2 Click the mouse on junction J7 Note how the mouse cursor changes shape to a pencil gt If you right click or press Enter after adding the first point of a subcatchment s outline the subcatchment will be shown as just a single point 11 3 Move the mouse over to junction J2 note how an outline of the conduit is drawn as you move the mouse and left click to create the conduit You could have cancelled the operation by either right clicking or by hitting the lt Esc gt key 4 Repeat this procedure for conduits C2 through C4 Although all of our conduits were drawn as straight lines it is possible to draw a curved link by left clicking at intermediate points where the direction of the link changes before clicking on the end node To complete the construction of our study area schematic we need to add a rain gage 1 Click the Rain Gage button on the Object Toolbar 2 Move the
44. data drawn in a separate window 3 If more rows in the data entry grid are needed as the series extends out in time simply press the Enter key when in the last row to append a new row to the grid 4 Right clicking over the Data Grid will make a popup Edit menu appear It contains commands to cut copy insert and paste selected cells in the grid as well as options to insert or delete a row Note that there are two methods for describing the occurrence time of time series data as calendar date time of day which requires that at least one date at the start of the series be entered in the Date column 45 elapsed hours since the start of the simulation where the Date column remains empty You can also click the Load button to load in a time series that was previously saved to file or click the Save button to save the current time series data to a file C 16 Title Notes Editor The Title Notes editor is invoked when a project s Title Notes data category is selected for editing As shown below the editor contains a multi line edit field where a description of a project can be entered It also contains a check box used to indicate whether or not the first line of notes should be used as a header for printing Project litle Motes E E E Example 3 Use of Pule Based Pump Controls and Dry Weather Flow Patterns Use title line as header for printing UK 203 C 17 Transect Editor The Transect Editor is invoked when
45. defined in terms of mass then a flow inflow time series is not required 189 Dry Weather Inflows Page The Dry Weather page of the Inflows Editor dialog is used to specify a continuous source of dry weather flow entering a node of the drainage system The dialog consists of the following input fields Inflows for Node 82309 Direct Drp Weather ROI Constituent CFS Time Pattems NOTE Leave Average Value field blank to remove any dry weather inflow for a given constituent at this node Constituent Selects the constituent FLOW or one of the project s specified pollutants whose dry weather inflow will be specified Average Value Specifies the average or baseline value of the dry weather inflow of the constituent in the relevant units flow units for flow concentration units for pollutants Leave blank if there is no dry weather flow for the selected constituent Time Patterns Specifies the names of the time patterns to be used to allow the dry weather flow to vary in a periodic fashion by month of the year by day of the week and by time of day for both weekdays and weekends One can either type in a name or select a previously defined pattern from the dropdown list of each combo box Up to four different types of patterns can be assigned You can click the Z button next to each Time Pattern field to edit the respective pattern 190 More than one constituent can be edited while the dialog is active by simpl
46. gt gt Map Options to bring up the Map Options dialog see Figure 2 3 Select the Subcatchments page set the Fill Style to Diagonal and the Symbol Size to 5 Then select the Nodes page and set the Node Size to 5 Select the Annotation page and check off the boxes that will display ID labels for Subcatchments Nodes and Links Leave the others un checked Finally select the Flow Arrows page select the Filled arrow style and set the arrow size to 7 Click the OK button to accept these choices and close the dialog Map Options Subcatchmente Fill Stple Clear O Solid Links 2 Diagonal L 7 Cross Hatch Nodes Labels Annotation Symbol SIze EEES Outline Thickness Flow Arrows Background Display link to outlet Figure 2 3 Map Options dialog Before placing objects on the map we should set its dimensions 1 Select View gt gt Dimensions to bring up the Map Dimensions dialog 2 Youcan leave the dimensions at their default values for this example Finally look in the status bar at the bottom of the main window and check that the Auto Length feature is off 2 3 Drawing Objects We are now ready to begin adding components to the Study Area Map We will start with the subcatchments 1 Begin by clicking the IA button on the Object Toolbar If the toolbar is not visible then select View gt gt Toolbars gt gt Object Notice how the mouse cursor changes shape to a pencil Drawing o
47. hr s12 average wind speed in December mph or km hr Stemp air temperature at which precipitation falls as snow deg F or C ATIwt antecedent temperature index weight default is 0 5 RNM negative melt ratio default is 0 6 Elev average elevation of study area above mean sea level ft or m default is 0 Lat latitude of the study area in degrees North default is 50 DTLong correction in minutes of time between true solar time and the standard clock time default is 0 0 fraction of area covered by snow when ratio of snow depth to depth at 100 cover is 0 Las fraction of area covered by snow when ratio of snow depth to depth at 100 cover is 0 9 Use the TIMESERIES line to read air temperature from a time series or the FILE line to read it from an external Climate file Climate files are discussed in Section 11 4 If neither format is used then air temperature remains constant at 70 degrees F Wind speed can be specified either by monthly average values or by the same Climate file used for air temperature If neither option appears then wind speed is assumed to be 0 Separate Areal Depletion Curves ADC can be defined for impervious and pervious sub areas The ADC parameters will default to 1 0 meaning no depletion if no data are supplied for a particular type of sub area 219 Section Purpose Format Remarks SUBCATCHMENTS Identifies each subcatchment within the study area Subcatchments ar
48. links are required This form of routing is insensitive to the time step employed and is really only appropriate for preliminary analysis using long term continuous simulations Kinematic Wave Routing This routing method solves the continuity equation along with a simplified form of the momentum equation in each conduit The latter requires that the slope of the water surface equal the slope of the conduit The maximum flow that can be conveyed through a conduit is the full normal flow value Any flow in excess of this entering the inlet node is either lost from the system or can pond atop the inlet node and be re introduced into the conduit as capacity becomes available Kinematic wave routing allows flow and area to vary both spatially and temporally within a conduit This can result in attenuated and delayed outflow hydrographs as inflow is routed through the channel However this form of routing cannot account for backwater effects entrance exit losses flow reversal or pressurized flow and is also restricted to dendritic network layouts It can usually maintain numerical stability with moderately large time steps on the order of 5 to 15 minutes If the aforementioned effects are not expected to be significant then this alternative can be an accurate and efficient routing method especially for long term simulations Dynamic Wave Routing Dynamic Wave routing solves the complete one dimensional Saint Venant flow equations and therefore p
49. listed in the CURVES section of the input Status status at start of simulation either ON or OFF default is ON Startup depth at inlet node when pump turns on ft or m default is 0 Shutoff depth at inlet node when pump shuts off ft or m default is 0 See Section 3 2 for a description of the different types of pumps available Section ORIFICES Purpose Identifies each orifice link of the drainage system An orifice link serves to limit the flow exiting a node and is often used to model flow diversions Format Name Nodel Node2 Type Offset Cd Flap Orate Remarks Name name assigned to orifice link Nodel name of node on inlet end of orifice Node2 name of node on outlet end of orifice Type orientation of orifice either SIDE or BOTTOM Offset amount that a Side Orifice s bottom or the position of a Bottom Orifice is offset above the invert of inlet node ft or m expressed as either a depth or as an elevation depending on the LINK_OFFSETS option setting Ca discharge coefficient unitless Flap YES if flap gate present to prevent reverse flow NO if not default is NO Orate time in decimal hours to open a fully closed orifice or close a fully open one Use 0 if the orifice can open close instantaneously The geometry of an orifice s opening must be described in the XSECTIONS section The only allowable shapes are CIRCULAR and RECT_CLOSED closed rectangular Regulator Orifice Structure Offset 229 Sectio
50. millimeters Initial Free Water Depth of melted water held within the pack at the start of the simulation inches or mm This number should be at or below the product of the initial snow depth and the fraction free water capacity Depth at 100 Cover The depth of snow beyond which the entire area remains completely covered and 19 not subject to any areal depletion effect inches or mm Fraction of Impervious Area That is Plowable The fraction of impervious area that is plowable and therefore is not subject to areal depletion 199 Snow Removal Parameters Page Snow Pack Editor Snow Pack Name P a Crow Pack Parametere Show Removal Parameters Depth at which snow removal begins mm Fraction transterred out of the watershed Fraction transfered to the impervious area Fraction transferred to the pervious area Fraction converted into immediate melt Fraction moved to another subcatchment Mame Note sum of all fractions must be lt 1 0 The Snow Removal page of the Snow Pack Editor describes how snow removal occurs within the Plowable area of a snow pack The following parameters govern this process Depth at which snow removal begins in or mm No removal occurs at depths below this and the fractions specified below are applied to the snow depths in excess of this number Fraction transferred out of the watershed The fraction of excess snow depth that is removed from the system and does not become runoff
51. mouse over the Study Area Map to where the gage should be located and left click the mouse At this point we have completed drawing the example study area Your system should look like the one in Figure 2 1 If a rain gage subcatchment or node is out of position you can move it by doing the following 1 If the button is not already depressed click it to place the map in Object Selection mode 2 Click on the object to be moved 3 Drag the object with the left mouse button held down to its new position To re shape a subcatchment s outline 1 With the map in Object Selection mode click on the subcatchment s centroid indicated by a solid square within the subcatchment to select it 2 Then click the button on the Map Toolbar to put the map into Vertex Selection mode 3 Select a vertex point on the subcatchment outline by clicking on it note how the selected vertex is indicated by a filled solid square 4 Drag the vertex to its new position with the left mouse button held down 5 If need be vertices can be added or deleted from the outline by right clicking the mouse and selecting the appropriate option from the popup menu that appears 6 When finished click the button to return to Object Selection mode This same procedure can also be used to re shape a link 2 4 Setting Object Properties As visual objects are added to our project SWMM assigns them a default set of properties To change the value of a specific prop
52. names of the links that form the loop will be listed following this message Node xxx has more than one outlet link Under Steady and Kinematic Wave flow routing a junction node can have only a single outlet link Node xxx has more than one DUMMY outlet link Only a single conduit with a DUMMY cross section can be directed out of a node Divider xxx does not have two outlet links Flow divider nodes must have two outlet links connected to them Divider xxx has invalid diversion link The link specified as being the one carrying the diverted flow from a flow divider node was defined with a different inlet node Weir Divider xxx has invalid parameters The parameters of a Weir type divider node either are non positive numbers or are inconsistent 1 e the value of the discharge coefficient times the weir height raised to the 3 2 power must be greater than the minimum flow parameter Node xxx has initial depth greater than maximum depth Self explanatory Regulator xxx is the outlet of a non storage node Under Steady or Kinematic Wave flow routing orifices weirs and outlet links can only be used as outflow links from storage nodes Outfall xxx has more than 1 inlet link or an outlet link An outfall node is only permitted to have one link attached to it Regulator xxx has invalid cross section shape An orifice must have either a CIRCULAR or RECT_CLOSED shape while a weir must have either a RECT_OPEN TRAPEZOIDAL or TRIANGU
53. node recommended for light colored backgrounds Link Options The Links page of the Map Options dialog controls how links are displayed on the map Option Link Size Proportional to Value Display Border Label Options Description Sets thickness of links displayed on map in pixels Select if link thickness should increase as the viewed parameter increases in value Check if a black border should be drawn around each link The Labels page of the Map Options dialog controls how user created map labels are displayed on the study area map Option Use Transparent Text At Zoom Of Description Check to display label with a transparent background otherwise an opaque background is used Selects minimum zoom at which labels should be displayed labels will be hidden at zooms smaller than this 100 Annotation Options The Annotation page of the Map Options dialog form determines what kind of annotation is provided alongside of the objects on the study area map Option Rain Gage IDs Subcatch Ds Node IDs Link IDs Subcatch Values Node Values Link Values Use Transparent Text Font Size At Zoom Of Symbol Options Description Check to display rain gage ID names Check to display subcatchment ID names Check to display node ID names Check to display link ID names Check to display value of current subcatchment variable Check to display value of current node variable Check to display value of cur
54. node was ever defined in the study area invalid number xxx at line n of input file Either a non numeric character was encountered where a numerical value was expected or an invalid number e g a negative value was supplied invalid date time xxx at line n of input file An invalid format for a date or time was encountered Dates must be entered as month day year and times as either decimal hours or as hour minute second control rule clause out of sequence at line n of input file Errors of this nature can occur when the format for writing control rules is not followed correctly see Section C 3 data provided for unidentified transect at line n of input file A GR line with Station Elevation data was encountered in the TRANSECTS section of the input file after an NC line but before any X1 line that contains the transect s ID name transect station out of sequence at line n of input file The station distances specified for the transect of an irregular cross section must be in increasing numerical order starting from the left bank Transect xxx has too few stations A transect for an irregular cross section must have at least 2 stations defined for it Transect xxx has too many stations A transect cannot have more than 1500 stations defined for it Transect xxx has no Manning s N No Manning s N was specified for a transect 1 e there was no NC line in the TRANSECTS section of the input file Transect xxx has inval
55. of our nation s waterways The EPA Stormwater Management Model is a computer program that can assess the impacts of such runoff and evaluate the effectiveness of mitigation strategies The modernized and updated version of the model described in this document will make it a more accessible and valuable tool for researchers and practitioners engaged in water resources and water quality planning and management Sally C Gutierrez Acting Director National Risk Management Research Laboratory ACKNOWLEDGEMENTS The development of SWMM 5 was pursued under a Cooperative Research and Development Agreement between the Water Supply and Water Resources Division of the U S Environmental Protection Agency and the consulting engineering firm of Camp Dresser amp McKee Inc The project team consisted of the following individuals US EPA CDM Lewis Rossman Robert Dickinson Trent Schade Carl Chan Daniel Sullivan retired Edward Burgess The team would like to acknowledge the assistance provided by Wayne Huber Oregon State University Dennis Lai US EPA and Michael Gregory CDM We also want to acknowledge the contributions made by the following individuals to previous versions of SWMM that we drew heavily upon in this new version John Aldrich Douglas Ammon Carl W Chen Brett Cunningham Robert Dickinson James Heaney Wayne Huber Miguel Medina Russell Mein Charles Moore Stephan Nix Alan Peltz Don Polmann Larry Roesner Charles Rowney and
56. rate TABULAR Curve Name Name of Rating Curve containing the relationship between head and flow rate double click to edit the curve B 12 Map Label Properties Text Text of label X Coordinate Horizontal location of the upper left corner of the label on the Study Area Map Y Coordinate Vertical location of the upper left corner of the label on the Study Area Map Anchor Node Name of node or subcatchment that anchors the label s position when the map is zoomed in i e the pixel distance between the node and the label remains constant Leave blank if anchoring is not used Click the ellipsis button or press Enter to modify the font used to draw the label Font 170 APPENDIX C SPECIALIZED PROPERTY EDITORS C 1 Aquifer Editor The Aquifer Editor is invoked whenever a new aquifer object is created or an existing aquifer object is selected for editing It contains the following data fields Name Aguifer Edit quier Editor User assigned aquifer name Property Value Aquifer Mame Al A Porosity Porosity 05 Volume of voids total soil volume volumetric fraction Wilting Point Field Capacity Wilting Point Conductivity Soil moisture content at which plants cannot survive volumetric fraction Conduct Slope Tension Slope Field Capacity Upper Evap Fraction Soil moisture content after all free water has drained off volumetric Lower E vap Depth fraction Lower Gi Lo
57. rearranged by using the Bj al TE and buttons underneath the list box 6 Click the OK button to view the profile plot To save the current set of links listed in the dialog for future use 1 Click the Save Current Profile button 2 Supply a name for the profile when prompted To use a previously saved profile 1 Click the Use Saved Profile button 2 Select the profile to use from the Profile Selection dialog that appears Profile plots can also be created before any simulation results are available to help visualize and verify the vertical layout of a drainage system Plots created in this manner will contain a refresh i button 2 in the upper left corner that can be used to redraw the plot after edits are made to any elevation data appearing in the plot Scatter Plots A Scatter Plot displays the relationship between a pair of variables such as flow rate in a pipe versus water depth at a node To create a Scatter Plot 1 Select Report gt gt Graph gt gt Scatter from the main menu or press on the Standard Toolbar 2 Specify what time interval and what pair of objects and their variables to plot using the Scatter Plot dialog that appears The Scatter Plot dialog is used to select the objects and variables to be graphed against one another in a scatter plot Use the dialog as follows 1 Select a Start Date and End Date for the plot the default is the entire simulation period 2 Select the following choices for
58. smaller than the specified conduit lengthening time step As this value is decreased fewer conduits will require lengthening A value of O the default means that no conduits will be lengthened VARIABLE_STEP is a safety factor applied to a variable time step computed for each time period under dynamic wave flow routing The variable time step is computed so as to satisfy the Courant stability criterion for each conduit and yet not exceed the ROUTING_STEP value If the safety factor is O the default then no variable time step is used INERTIAL DAMPING indicates how the inertial terms in the Saint Venant momentum equation will be handled under dynamic wave flow routing Choosing NONE maintains these terms at their full value under all conditions Selecting PARTIAL will reduce the terms as flow comes closer to being critical and ignores them when flow is supercritical Choosing FULL will drop the terms altogether NORMAL FLOW_LIMITED specifies which condition is checked to determine if flow in a conduit is supercritical and should thus be limited to the normal flow Use SLOPE to check if the water surface slope is greater than the conduit slope FROUDE to check if the Froude number is greater than 1 0 or BOTH to check both conditions The default is BOTH 215 MIN_SURFAREA is a minimum surface area used at nodes when computing changes in water depth under dynamic wave routing If O is entered then the default value of 12 566 ft2 1 e t
59. snow removal by plowing but not to areal depletion This area is the fraction SNNO of the total impervious area The IMPERVIOUS line contains parameter values for the remaining impervious area and the PERVIOUS line does the same for the entire pervious area Both of the latter two areas are subject to areal depletion The REMOVAL line describes how snow removed from the plowable area is transferred onto other areas The various transfer fractions should either sum to 1 0 or be all 0 0 to indicate that no plowing is done or the line can simply be omitted 224 Section JUNCTIONS Purpose Identifies each junction node of the drainage system Junctions are points in space where channels and pipes connect together For sewer systems they can be either connection fittings or manholes Format Name Elev Ymax YO Ysur Apond Remarks Name name assigned to junction node Elev elevation of junction invert ft or m Ymax depth from ground to invert elevation ft or m default is 0 YQ water depth at start of simulation ft or m default is 0 Ysur maximum additional head above ground elevation that manhole junction can sustain under surcharge conditions ft or m default is 0 Apond area subjected to surface ponding once water depth exceeds Ymax ft2 or m2 default is Q Section OUTFALLS Purpose Identifies each outfall node e final downstream boundary of the drainage system and the corresponding water stage elevation
60. supplies groundwater Leave this field blank if you want the subcatchment not to generate any groundwater flow Receiving Node Name of node that receives groundwater from the aquifer Surface Elevation Elevation of ground surface for the subcatchment that lies above the aquifer in feet or meters Groundwater Flow Coefficient Value of Al in the groundwater flow formula Groundwater Flow Exponent Value of B1 in the groundwater flow formula Surface Water Flow Coefficient Value of A2 in the groundwater flow formula Surface Water Flow Exponent Value of B2 in the groundwater flow formula Surface GW Interaction Coefficient Value of A3 in the groundwater flow formula Fixed Surface Water Depth Fixed depth of surface water at the receiving node feet or meters set to zero if surface water depth will vary as computed by flow routing Threshold Groundwater Elevation Aquifer water table elevation which must be reached before any ground water flow occurs feet or meters Leave blank to use the receiving node s invert elevation 184 The values of the flow coefficients must be in units that are consistent with the groundwater flow units of cfs acre for US units or cms ha for metric units Y If groundwater flow is simply proportional to the difference in groundwater and surface water heads then set the Groundwater and Surface Water Flow Exponents B1 and B2 to 1 0 set the Groundwater Flow Coefficient A1 to the proportionalit
61. term and long term responses respectively as well as parameters that describe any initial abstraction losses The editor contains the following data entry fields Unit Hydrograph Editor Mame of UH Group Rain Gage Hidrograph Parameters Games rove Tne ATT January 2 E February Short Term 0 5 March M au July August F fraction of rainfall that becomes Il September October T time to hydrograph peak hours November K falling limb duration ema limb duration December a Initial Abstraction Parameters Recover Rate in day 4 1 Initial Depth in 0 0 Name of UH Group Enter the name assigned to the UH Group Rain Gage Type in or select from the dropdown list the name of the rain gage that supplies rainfall data to the unit hydrographs in the group Month Select a month from the list box for which hydrograph parameters will be defined Select ALL MONTHS to specify a default set of hydrographs that apply to all months of the year Then select specific months that need to have special hydrographs defined 206 R T K Parameters Grid Use this data grid to provide the R T K shape parameters for each set of unit hydrographs in selected months of the year The first row is used to specify parameters for a short term response hydrograph 1 e small value of T the second for a medium term response hydrograph and the third for a long term response hydrograph largest value of T It is not required that
62. that appears first is given the higher priority Condition Clauses A Condition Clause of a control rule has the following format object id attribute relation value where object acategory of object 1d the object s ID label attribute an attribute or property of the object relation arelational operator lt gt lt lt gt gt value an attribute value Some examples of condition clauses are NODE NZS DEPTH 2 10 PUMP P435 STATUS OFF SIMULATION CLOCKTIME 22 45 00 The objects and attributes that can appear in a condition clause are as follows DEPTH HEAD INFLOW NODE LINK FLOW DEPTH PUM STATUS FLOW ORIFICE SETTING WEIR SIMULATION TIME DATE CLOCKTIME numerical value numerical value numerical value numerical value numerical value ON or OFF numerical value fraction open elapsed time in decimal hours or hr min sec month day year time of day in hr min sec 179 Action Clauses An Action Clause of a control rule can have one of the following formats PUMP id STATUS ON OFF PUMP ORIFICE WEIR OUTLET id SETTING value where the meaning of SETTING depends on the object being controlled for Pumps it is a multiplier applied to the flow computed from the pump curve for Orifices it is the fractional amount that the orifice is fully open for Weirs it is the fractional amount of the original freeboard that exists 1 e weir control is accomplishe
63. that are in effect Click the drop down arrow to change the choice of flow units Selecting a US flow unit means that all other quantities will be expressed in US units while choosing a metric flow unit will force all quantities to be expressed in metric units The units of previously entered data are not automatically adjusted if the unit system is changed 65 Run Status A faucet icon shows no running water if simulation results are not available running water when simulation results are available a broken faucet when simulation results are available but may be invalid because project data have been modified Zoom Level Displays the current zoom level for the map 100 is full scale XY Location Displays the map coordinates of the current position of the mouse pointer 4 5 Study Area Map The Study Area Map shown below provides a planar schematic diagram of the objects comprising a drainage system Its pertinent features are as follows Study Area Map ol x The location of objects and the distances between them do not necessarily have to conform to their actual physical scale Selected properties of these objects such as water quality at nodes or flow velocity in links can be displayed by using different colors The color coding is described in a Legend which can be edited New objects can be directly added to the map and existing objects can be selected for editing deleting and repositioning
64. the X variable the quantity plotted along the horizontal axis a Object Category Subcatchment Node or Link b Object ID enter a value or click on the object either on the Study Area Map or in the Data Browser and then click the button on the dialog c Variable to plot choices depend on the category of object selected 3 Do the same for the Y variable the quantity plotted along the vertical axis 4 Click the OK button to create the plot 123 Scatter Plot Start Date End Date 01701 1338 w 01702 1998 Ww arable T M arable Object Category Object Category Object Object a CIC O V arable Varable 9 5 Customizing a Graph s Appearance To customize the appearance of a graph 1 Make the graph the active window click on its title bar 2 Select Report gt gt Customize from the Main Menu or click on the Standard Toolbar or right click on the graph 3 Use the Graph Options dialog that appears to customize the appearance of a Time Series or Scatter Plot or use the Profile Plot Options dialog for a Profile Plot Graph Options Dialog The Graph Options dialog is used to customize the appearance of a time series plot or a scatter plot To use the dialog 1 Select from among the five tabbed pages that cover the following categories of options General Horizontal Axis Vertical Axis Legend and Series 2 Check the Default box if you wish to use the current settings as defaults for all new graphs as well
65. the amount of pollutant buildup existing over the subcatchment at the start of the simulation The editor consists of a data entry grid with two columns The first column lists the name of each pollutant in the project and the second column contains edit boxes for entering the initial buildup values If no buildup value is supplied for a pollutant it is assumed to be O The units for buildup are either pounds per acre when US units are in use or kilograms per hectare when SI metric units are in use Subcatchment 1 Initial Buildup Editor Pollutant Initial Buildup lbs ac H Pery 0 10 4 IS Dstore lmpery 0 05 Lead Dstore Pery 0 05 ero PPery 25 Subarea Routing OUTLET Percent Routed 100 Infiltration HORTON Enter initial buildup of pollutants on subcatchment 1 Groundwater Snow Pack Initial Buildup art Curb Length Initial pollutant buildup on subcatchmert click to edit If a non zero value is specified for the initial buildup of a pollutant it will override any initial buildup computed from the Antecedent Dry Days parameter specified on the Dates page of the Simulation Options dialog C 10 Land Use Editor The Land Use Editor dialog is used to define a category of land use for the study area and to define its pollutant buildup and washoff characteristics The dialog contains three tabbed pages of land use properties General Page provides land use name and street sweeping parameters Buildup Page defines rat
66. type e g intensity or volume recording time interval and depth units must also be supplied as rain gage properties For the other file types these properties are defined by their respective file format and are automatically recognized by SWMM 11 4 Climate Files SWMM can use an external climate file that contains daily air temperature evaporation and wind speed data The program currently recognizes the following formats A DSI 3200 or DSI 3210 file available from the National Climatic Data Center at www ncdc noaa gov oa ncdc html Canadian climate files available from Environment Canada at www climate weatheroffice ec gc ca 140 A user prepared climate file where each line contains a recording station name the year month day maximum temperature minimum temperature and optionally evaporation rate and wind speed If no data are available for any of these items on a given date then an asterisk should be entered as its value When a climate file has days with missing values SWMM will use the value from the most recent previous day with a recorded value Y 11 5 For a user prepared climate file the data must be in the same units as the project being analyzed For US units temperature is in degrees F evaporation is in inches day and wind speed is in miles hour For metric units temperature is in degrees C evaporation is in mm day and wind speed is in km hour Calibration Files Calibration files contain meas
67. unit feet or meters or meters Max Depth Max Depth Maximum depth of the storage unit feet or meters Maximum depth of the storage unit feet or meters Initial Depth Initial depth of water in the storage unit at the start of the simulation feet or meters Ponded Area Surface area occupied by ponded water atop the storage unit once the water depth exceeds the maximum depth sq feet or sq meters See description for Junctions Evap Factor The fraction of the potential evaporation from the storage unit s water surface that is actually realized Shape Curve Method of describing the geometric shape of the storage unit FUNCTIONAL uses the function Area A Depth B C to describe how surface area varies with depth TABULAR uses a tabulated area versus depth curve In either case depth is measured in feet or meters and surface area in area in sq feet or sq meters 0 feet or sq meters FUNCTIONAL Coeff in the functional relationship between surface area and storage depth Exponent B value in the functional relationship between surface area and storage depth Constant C value in the functional relationship between surface area and Seem A depth TAB TABULAR Curve Name Name a the Storage Curve containing the relationship between surface area and storage depth double click to edit the curve 166 B 7 Conduit Properties Name User assigned conduit name Inlet No
68. AMPEN reduces the terms as flow comes closer to being critical and ignores them when flow is supercritical IGNORE drops the terms altogether from the momentum equation producing what is essentially a Diffusion Wave solution Define Supercritical Flow By Selects the basis used to determine when supercritical flow occurs in a conduit The choices are water surface slope only 1 e water surface slope gt conduit slope Froude number only 1 e Froude number gt 1 0 both water surface slope and Froude number The first two choices were used in earlier versions of SWMM while the third choice which checks for either condition is now the recommended one Force Main Equation Selects which equation will be used to compute friction losses during pressurized flow for conduits that have been assigned a Circular Force Main cross section The choices are either the Hazen Williams equation or the Darcy Weisbach equation Use Variable Time Step Check the box if an internally computed variable time step should be used at each routing time period and select an adjustment or safety factor to apply to this time step The variable time step is computed so as to satisfy the Courant condition within each conduit A typical adjustment factor would be 75 to provide some margin of conservatism The computed variable time step will not be less than 0 5 seconds nor be greater than the fixed time step specified on the Time 108 Steps page of
69. BMPs entry of dry weather sanitary flows and user specified external inflows at any point in the drainage system routing of water quality constituents through the drainage system reduction in constituent concentration through treatment in storage units or by natural processes in pipes and channels Typical Applications of SWMM Since its inception SWMM has been used in thousands of sewer and stormwater studies throughout the world Typical applications include design and sizing of drainage system components for flood control sizing of detention facilities and their appurtenances for flood control and water quality protection flood plain mapping of natural channel systems designing control strategies for minimizing combined sewer overflows evaluating the impact of inflow and infiltration on sanitary sewer overflows generating non point source pollutant loadings for waste load allocation studies evaluating the effectiveness of BMPs for reducing wet weather pollutant loadings 1 4 Installing EPA SWMM EPA SWMM Version 5 is designed to run under the Windows 98 NT ME 2000 XP Vista operating system of an IBM Intel compatible personal computer It is distributed as a single file epaswmm5_setup exe which contains a self extracting setup program To install EPA SWMM 1 Select Run from the Windows Start menu 2 Enter the full path and name of the epaswmm5_setup exe file or click the Browse button to locate it on your computer 3 Clic
70. C2 SweepEffic BMPEffic Landuse land use name Pollutant pollutant name FuncType washoff function type EXP RC EMC Cl C2 washoff function coefficients see Table D 3 SweepEffic street sweeping removal efficiency percent BMPEffic BMP removal efficiency percent Table D 3 Pollutant wash off functions Name Function Equation Units EMC Event Mean Cl Mass Liter Concentration Each washoff function expresses its results in different units For the Exponential function the runoff variable is expressed in catchment depth per unit of time inches per hour or millimeters per hour while for the Rating Curve function it is in whatever flow units were specified in the OPTIONS section of the input file e g CFS CMS etc The buildup parameter in the Exponential function is the current buildup over the subcatchment s land use area in mass units The units of C1 in the Exponential function are in hr ps per hour or mm hr i per hour For the Rating Curve function the units of C1 depend on the flow units employed For the EMC event mean concentration function C1 is always in concentration units 241 Section TREATMENT Purpose Specifies the degree of treatment received by pollutants at specific nodes of the drainage system Format Node Pollut Result Func Remarks Node Name of node where treatment occurs Pollut Name of pollutant receiving treatment Result Result computed by treatment function C
71. E R2A IF NODE 23 DEPTH gt 12 AND LINK 165 FLOW gt 100 THEN ORIFICE R55 SETTING 0 5 RULE R2B IF NODE 23 DEPTH gt 12 AND LINK 165 FLOW gt 200 THEN ORIFICE R55 SETTING 1 0 RULE R2C IF NODE 23 DEPTH lt 12 OR LINK 165 FLOW lt 100 THEN ORIFICE R55 SETTING 0 Pump station operation RULE R3A IF NODE N1 DEPTH gt 5 THEN PUMP NIA STATUS ON RULE R3B IF NODE N1 DEPTH gt 7 THEN PUMP NIB STATUS ON RULE R3C IF NODE N1 DEPTH lt 3 THEN PUMP NIA STATUS OFF AND PUMP NIB STATUS OFF 48 Modulated weir height control RULE R4 IF NODE N2 DEPTH gt 0 THEN WEIR W25 SETTING CURVE C25 Appendix C 3 describes the control rule format in more detail and the special Editor used to edit them 3 3 8 Pollutants SWMM can simulate the generation inflow and transport of any number of user defined pollutants Required information for each pollutant includes pollutant name concentration units 1 e milligrams liter micrograms liter or counts liter concentration in rainfall concentration in groundwater concentration in direct infiltration inflow first order decay coefficient Co pollutants can also be defined in SWMM For example pollutant X can have a co pollutant Y meaning that the runoff concentration of X will have some fixed fraction of the runoff concentration of Y added to it Pollutant buildup and washoff from subcatchment areas are determined by the land uses assigned to th
72. Eof set Elev station e Neighe Nchanl Nsta xXleft Xright 0 0 0 Wfactor Eoffset SEACION esa lev otation Manning s n of right overbank portion of channel use O if no change from previous NC line Manning s n of right overbank portion of channel use O if no change from previous NC line Manning s n of main channel portion of channel use 0 if no change from previous NC line name assigned to transect number of stations across cross section at which elevation data is supplied station position which ends the left overbank portion of the channel ft or m station position which begins the right overbank portion of the channel ft or m factor by which distances between stations should be multiplied to increase or decrease the width of the channel enter 0 1f not applicable amount added or subtracted from the elevation of each station ft or m elevation of the channel bottom at a cross section station relative to some fixed reference ft or m distance of a cross section station from some fixed reference ft or m Transect geometry 19 described as shown below assuming that one is looking in a downstream direction Ele wation verbank xl eft o Xright Station The first line in this section must always be a NC line After that the NC line is only needed when a transect has different N values than the previous one The Manning s n values on the NC line will supersede any roughness valu
73. F divider flow units TABULAR DIVIDER Curve Name Name of Diversion Curve used with a TABULAR divider double click to edit the curve WEIR DIVIDER Min Flow Minimum flow at which diversion begins for a WEIR divider flow units Max Depth Vertical height of WEIR opening feet or meters Coefficient Product of WEIR s discharge coefficient and its length Weir coefficients are typically in the range of 2 65 to 3 10 per foot for flows in CFS 165 B 6 Storage Unit Properties Name User assigned storage unit name X Coordinate Horizontal location of the storage unit on the Study Area Map If left blank then the storage unit will not appear on the map Y Coordinate Vertical location of the storage unit on the Study Area Map If left blank then the storage unit will not appear on the map Description Click the ellipsis button or press Enter to edit an optional description of the storage unit Tag sts Tag Optional label used to categorize or classify the storage unit Optional label used to categorize or classify the storage unit Inflows Click the ellipsis button or press Enter to assign external direct dry weather or RDII inflows to the storage unit Treatment Click the ellipsis button or press Enter to edit a set of treatment functions for ee R SME e SOES M a o entering the storage unit Invert E El Elevation of the bottom of the storage unit Elevation of the bottom of the storage
74. HENING_STEP seconds VARIABLE STEP value INERTIAL DAMPING NONE PARTIAL FULL NORMAL FLOW_LIMITED SLOPE FROUDE BOTH MIN SURFAREA value TEMPDIR directory Remarks FLOW_UNITS makes a choice of flow units Selecting a US flow unit means that all other quantities will be expressed in US units while choosing a metric flow unit will force all quantities to be expressed in metric units The default is CFS INFILTRATION selects a model for computing infiltration of rainfall into the upper soil zone of subcatchments The default model is HORTON 213 FLOW_ROUTING determines which method is used to route flows through the drainage system STEADY refers to sequential steady state routing i e hydrograph translation KINWAVE to kinematic wave routing DYNWAVE to dynamic wave routing and NONE is used to simulate runoff only The default routing method is KINWAVE LINK_OFFSETS determines the convention used to specify the position of a link offset above the invert of its connecting node DEPTH indicates that offsets are expressed as the distance between the node invert and the link while ELEVATION indicates that the absolute elevation of the offset is used FORCE MAIN EQUATION establishes whether the Hazen Williams H W or the Darcy Weisbach D W equation will be used to compute friction losses for pressurized flow in conduits that have been assigned a Circular Force Main cross section shape The default is H W IGNORE_RAINFALL is set to
75. II 100 Variable Time Step A FII 0 e LL 200 0 Time hours Flow time series plots for the links having the highest FII s should be inspected to insure that flow routing results are acceptably stable 113 Numerical instabilities under Dynamic Wave flow routing can be reduced by reducing the routing time step utilizing the variable time step option with a smaller time step factor selecting to ignore the inertial terms of the momentum equation selecting the option to lengthen short conduits 114 CHAPTER 9 VIEWING RESULTS This chapter describes the different ways in which the results of a simulation can be viewed These include a status report various map views graphs tables and a statistical frequency report 9 1 Viewing a Status Report A Status Report is available for viewing after each simulation It contains a summary of the main Simulation Options that are in effect a list of any error conditions encountered during the run a summary listing of the project s input data if requested in the Simulation Options a summary of the data read from each rainfall file used in the simulation a description of each control rule action taken during the simulation if requested in the Simulation Options the system wide mass continuity errors for o runoff quantity and quality o groundwater flow o conveyance system flow and water quality the names of the nodes with the highest individual fl
76. LAR shape Drainage system has no acceptable outlet nodes Under Dynamic Wave flow routing there must be at least one node designated as an outfall a Unit Hydrograph in set xxx has invalid time base The time base of a Unit hydrograph must be greater than 0 256 ERROR 153 ERROR 155 ERROR 161 ERROR 171 ERROR 173 ERROR 181 ERROR 182 ERROR 191 ERROR 193 ERROR 195 ERROR 200 ERROR 201 ERROR 203 ERROR 205 a Unit Hydrograph in set xxx has invalid response ratios The response ratios for a set of Unit Hydrographs the short medium and long term response hydrographs must be between O and 1 0 and cannot add up to a value greater than 1 0 invalid sewer area for RDII at Node xxx The sewer area contributing RDII inflow to a node cannot be a negative number cyclic dependency in treatment functions at Node xxx An example would be where the removal of pollutant 1 is defined as a function of the removal of pollutant 2 while the removal of pollutant 2 is defined as a function of the removal of pollutant 1 Curve xxx has its data out of sequence The X values of a curve object must be entered in increasing order Time Series xxx has its data out of sequence The time or date time values of a time series must be entered in sequential order invalid Snow Melt Climatology parameters The ATI Weight or Negative Melt Ratio parameters are not between U and or the site latitude is not
77. Ma Capacity Cancel The Time Series Plot dialog describes the objects and variable to be graphed in a time series plot Time series for certain system wide variables such as total rainfall total runoff total flooding etc can also be plotted Use the dialog as follows 1 Select a Start Date and End Date for the plot the default is the entire simulation period 2 Choose whether to show time as Elapsed Time or as Date Time values 3 Choose an Object Category Subcatchment Node Link or System for plotting 4 Ifthe object category is not System identify the objects to plot by a selecting the object either on the Study Area Map or in the Data Browser b clicking the button on the dialog to add it to the plot c repeating these steps for any additional objects of the same category 5 Select a simulated variable to be plotted The available choices depend on the category of object selected 6 Click the OK button to create the plot A maximum of 6 objects can be selected for a single plot Objects already selected can be deleted TE moved up in the order or moved down in the order by clicking the LZ e and buttons respectively 121 Profile Plots A Profile Plot displays the variation in simulated water depth with distance over a connected path of drainage system links and nodes at a particular point in time Once the plot has been created it will be automatically updated as a new time period is selec
78. Only one link can be incident on an outfall node Formats Name Elev FREE Gate Name Elev NORMAL Gate Name Elev FIXED Stage Gate Name Elev TIDAL Tcurve Gate Name Elev TIMESERIES Tseries Gate Remarks Name name assigned to outfall node Elev invert elevation ft or m Stage elevation of fixed stage outfall ft or m Tcurve name of curve in CURVES section containing tidal height 1 e outfall stage v hour of day over a complete tidal cycle Tseries name of time series in TIMESERIES section that describes how outfall stage varies with time Gate YES or NO depending on whether a flap gate is present that prevents reverse flow 225 Section Purpose Formats Remarks DIVIDERS Identifies each flow divider node of the drainage system Flow dividers are junctions with exactly two outflow conduits where the total outflow is divided between the two in a prescribed manner Name Name Name Name Name Elev DivLink Omin Dcurve Ht Cd Ymax YO Ysur Apond Elev DivlLink OVERFLOW Ymax YO Ysur Apond Elev Divlink CUTOFF Qmin Ymax YO Ysur Apond Elev DivLink TABULAR Dcurve Ymax YO Ysur Apond Elev DivLink WEIR Omin HE Cd Imax YO Ysur Apond name assigned to divider node invert elevation ft or m name of link to which flow is diverted flow at which diversion begins for either a CUTOFF or WEIR divider flow units name of curve for TABULAR divider that relates diverted flow to total flow
79. Pumps are links used to lift water to higher elevations A pump curve describes the relation between a pump s flow rate and conditions at its inlet and outlet nodes Four different types of pump curves are supported Typel An off line pump with a wet well where flow increases incrementally with available wet well volume Flow olume Type2 An in line pump where flow increases incrementally with inlet node depth Flow Depth Type3 An in line pump where flow varies continuously with head difference between the inlet and outlet nodes Flor Head Type4 A variable speed in line pump where flow varies continuously with inlet node depth Flow Depth Ideal An ideal transfer pump whose flow rate equals the inflow rate at its inlet node No curve is required The pump must be the only outflow link from its inlet node Used mainly for preliminary design The on off status of pumps can be controlled dynamically by specifying startup and shutoff water depths at the inlet node or through user defined Control Rules Rules can also be used to simulate variable speed drives that modulate pump flow The principal input parameters for a pump include names of its inlet and outlet nodes name of its pump curve 40 initial on off status startup and shutoff depths 3 2 9 Flow Regulators Flow Regulators are structures or devices used to control and divert flows within a conveyance system They ar
80. RATION subcatchment infiltration parameters AQUIFERS groundwater aquifer parameters GROUNDWATER subcatchment groundwater parameters SNOWPACKS subcatchment snow pack parameters JUNCTIONS junction node information OUTFALLS outfall node information DIVIDERS flow divider node information STORAGE storage node information 209 CONDUITS conduit link information PUMPS pump link information ORIFICES orifice link information WEIRS weir link information OUTLETS outlet link information XSECTIONS conduit orifice and weir cross section geometry TRANSECTS transect geometry for conduits with irregular cross sections LOSSES conduit entrance exit losses and flap valves CONTROLS rules that control pump and regulator operation POLLUTANTS pollutant information LANDUSES land use categories COVERAGES assignment of land uses to subcatchments BUILDUP buildup functions for pollutants and land uses WASHOF F washoff functions for pollutants and land uses TREATMENT pollutant removal functions at conveyance system nodes INFLOWS external hydrograph pollutograph inflow at nodes DWE baseline dry weather sanitary inflow at nodes PATTERNS periodic variation in dry weather inflow RDI1 rainfall dependent I I information at nodes LOADINGS initial pollutant loads on subcatchments CURVES x y tabular data referenced in other sections TIMESERIES time series data referenced in other sections The sections can a
81. Recording time interval between gage readings in either decimal 161 B 2 Subcatchment Properties Name User assigned subcatchment name X Coordinate Horizontal location of the subcatchment s centroid on the Study Area Map If left blank then the subcatchment will not appear on the map Y Coordinate Vertical location of the subcatchment s centroid on the Study Area Map If left blank then the subcatchment will not appear on the map Description Click the ellipsis button or press Enter to edit an optional description of the subcatchment mea Tag SS e Optional label used to categorize or classify the subcatchment Rain Rain Gage Name Name of the rain gage associated with the subcatchment the rain gage associated with the subcatchment Outlet Name of the node or subcatchment which receives the subcatchment s runoff Area Area Area of the subcatchment acres or hectares Area of the subcatchment acres or hectares Width Characteristic width of the overland flow path for sheet flow runoff feet or meters An initial estimate of the characteristic width is given by the subcatchment area divided by the average maximum overland flow length The maximum overland flow length is the length of the flow path from the inlet to the furthest drainage point of the subcatchment Maximum lengths from several different possible flow paths should be averaged These paths should reflect slow flow such as over pervious su
82. Release the mouse button The following alternative method can also be used 1 Select the object to be moved from the Data Browser it must either be a rain gage subcatchment node or map label 2 With the left mouse button held down drag the item from the Items list box of the Data Browser to its new location on the map 3 Release the mouse button Note that the second method can be used to place objects on the map that were imported from a project file that had no coordinate information included in it 6 4 Editing Objects To edit an object appearing on the Study Area Map 1 Select the object on the map 2 If the Property Editor is not visible either double click on the object or right click on the object and select Properties from the pop up menu that appears or click on in the Data Browser 3 Edit the object s properties in the Property Editor Appendix B lists the properties associated with each of SWMM s visual objects To edit an object listed in the Data Browser 1 Select the object in the Data Browser 2 Either click on Z in the Data Browser or double click the item in the Objects list or press the lt Enter gt key 84 Depending on the class of object selected a special property editor will appear in which the object s properties can be modified Appendix C describes all of the special property editors used with SWMM s non visual objects y The unit system in which objec
83. S RESIDENTIAL UNDEVELOPED WASHOFF 77 Landuse Pollutant Type Coeff Expon SweepEff BMPEff RESIDENTIAL TSS EMC 23 4 U U U UNDEVELOPED TSS EMC 12 1 U U U COVERAGES oF Subcatch Landuse Pent Landuse Pent AREA1 RESIDENTIAL 80 UNDEVELOPED 20 AREA2 RESIDENTIAL 55 UNDEVELOPED 45 TIMESERIES Rainfall time series SERIE SL OO Og Ue ies EaU C250 Oud SERIES1 0 45 Dord T400 0 0 2400 0730 REPORT INPUT YES SUBCATCHMENTS ALL NODES ALL LINKS C4 C3 C6 Figure D 1 Example SWMM project file continued from previous page 212 Section TITLE Purpose Attaches a descriptive title to the problem being analyzed Format Any number of lines may be entered The first line will be used as a page header in the output report Section OPTIONS Purpose Provides values for various analysis options Format FLOW_UNITS CFS GPM MGD CMS LPS MLD INFILTRATION HORTON GREEN AMPT CURVE NUMBER FLOW_ROUTING STEADY KINWAVE DYNWAVE NONE LINK_OFFSETS DEPTH ELEVATION FORCE_MAIN EQUATION H W D W IGNORE_RAINFALL YES NO ALLOW_PONDING YES NO SKIP_STEADY STATE YES NO START_DATE month day year START_TIME hours minutes END_DATE month day year END_ TIME hours minutes REPORT_START_DATE month day year REPORT_START_TIME hours minutes SWEEP_START month day SWEEP_END month day DRY DAYS days REPORT_STEP hours minutes seconds WET_STEP hours minutes seconds DRY_STEP hours minutes seconds ROUTING_STEP seconds LENGT
84. SUAL OBJECT PROPERTIES sss sss sss sees sese seene nenen 161 B 1 Rain Gace Ke a LT 161 B 2 Subcatchment Properties rt H 162 B 3 J nc ON Propere Seien E 163 B 4 Ow a sake oY 8 ex Dc 164 B 5 Flow Divider Properties as i 165 B 6 Storage Unit e ae TTT 166 B 7 ele OPC TTT 167 B 8 LUTO POTTIER arco 168 B 9 Onee A o anouseua tageeesSecgacieeteiceneanguse 168 BA Wer Properties e an da dd 169 BAT Quick Properties ia ais 170 BA Map Label Eropertes critica tico iacnahenetees 170 APPENDIX C SPECIALIZED PROPERTY EDITORS sss sese ssss sese ee senenn neee 171 C l AQUI dolido ll RARE eT 171 C 2 96 TRT Ce erent Elton 172 C 3 Control Rules Se T 177 C 4 TOSS AAA as eceal en eu ta cesan anaes eteeea Aaa duane 181 CD CUE ello eee te mtr NS 182 C 6 Groundwater Flow Sa esiisa aaa 183 C7 IST RT Re aT gat ans E E sess ev gated oa EA ET 185 C 8 OWEN oo oca 188 C 9 Inua s ee Edit 192 EMO Lado dl Ed 192 CAL Wandise Assiominient Ed ti 196 CA Polun Edda dido in ads 197 tio STs Lar o O ud a 198 Cura Time Patter Pdo 201 Esto Lime Senos Edo didas 202 Calg MEN ES A o 203 CA Transe EONO batave E E ee eae es 204 Cols TEreatiment Edi 205 C19 Um Ey GOS PME O aviat lealtades 206 APPENDIX D COMMAND LINE SVWWMM ssss sss sss ssc esc es esse enean enean ee 209 APPENDIX E ERROR MESSAGES css s sss ss sese sese 255 CHAPTER 1 INTRODUCTION 1 1 What is SWMM The EPA Storm Water Management Model SWMM is
85. SurfEl surface elevation of subcatchment ft or m Al groundwater flow coefficient see below B1 groundwater flow exponent see below A2 surface water flow coefficient see below B2 surface water flow exponent see below A3 surface water groundwater interaction coefficient see below TW fixed depth of surface water at receiving node ft or m set to zero if surface water depth will vary as computed by flow routing E groundwater elevation which must be reached before any flow occurs feet or meters Leave blank to use the receiving node s invert elevation The flow coefficients are used in the following equation that determines a groundwater flow rate based on groundwater and surface water elevations Q Al H E A2 H E A3H H where O groundwater flow cfs per acre or cms per hectare Ho computed elevation of groundwater table ft or m He computed elevation of surface water at receiving node ft or m if TW is O or TW E otherwise 223 Section Purpose Formats Remarks SNOWPACKS Specifies parameters that govern how snowfall accumulates and melts on the plowable impervious and pervious surfaces of subcatchments Name PLOWABLE Cmin Cmax Tbase FWF SDO FWO SNNO Name IMPERVIOUS Cmin Cmax Tbase FWF SDO FWO SD100 Name PERVIOUS Cmin Cmax Tbase FWF SDO FWO SDI100 Name REMOVAL Dplow Fout Fimp Fperv Fimelt Fsub Scatch Name name assigned to snowpack paramet
86. The scale factor can have several uses such as allowing one to easily change the magnitude of an inflow hydrograph while keeping its shape the same without having to re edit the entries in the hydrograph s time series Or it can allow a group of nodes sharing the same time series to have their inflows behave in a time synchronized fashion while letting their individual magnitudes be different If left blank the scale factor defaults to 1 0 Inflow Type For pollutants selects the type of inflow data contained in the time series as being either a concentration mass volume or mass flow rate mass time This field does not appear for FLOW inflow Conversion Factor A numerical factor used to convert the units of pollutant mass flow rate in the time series data into concentration mass units per second For example if the time series data were in pounds per day and the pollutant concentration defined in the project was mg L then the conversion factor value would be 453 590 mg Ib 86400 sec day 5 25 mg sec per Ib day More than one constituent can be edited while the dialog is active by simply selecting another choice for the Constituent property However if the Cancel button is clicked then any changes made to all constituents will be ignored Y If a pollutant is assigned a direct inflow in terms of concentration then one must also assign a direct inflow to flow otherwise no pollutant inflow will occur If pollutant inflow is
87. Time series plot of results from initial simulation run 21 After a plot is created you can customize its appearance by selecting Report gt gt Customize or right clicking on the plot copy it to the clipboard and paste it into another application by selecting Edit gt gt Copy To or clicking Ba lon the Standard Toolbar print it by selecting File gt gt Print or File gt gt Print Preview use File gt gt Page Setup first to set margins orientation etc Viewing a Profile Plot SWMM can generate profile plots showing how water surface depth varies across a path of connected nodes and links Let s create such a plot for the conduits connecting junction JZ to the outfall Out of our example drainage system To do this 1 Select Report gt gt Graph gt gt Profile or simply click Ey on the Standard Toolbar 2 Either enter JZ in the Start Node field of the Profile Plot dialog that appears see Figure 2 14 or select 1t on the map or from the Data Browser and click the button next to the field Profile Plot Create Protile Links in Profile Start Mode C E El End Node w E Find Path Save Current Profile eje Figure 2 14 Profile Plot dialog 3 Do the same for node Out in the End Node field of the dialog 4 Click the Find Path button An ordered list of the links forming a connected path between the specified Start and End nodes will be displayed in the Links in Profile box You can edit the entrie
88. _TIME is the time of day on the report starting date when reporting is to begin The default is the simulation start time of day 214 SWEEP_START is the day of the year month day when street sweeping operations begin The default is 1 1 SWEEP_END is the day of the year month day when street sweeping operations end The default is 12 31 DRY_DAYS is the number of days with no rainfall prior to the start of the simulation The default is 0 REPORT_STEP is the time interval for reporting of computed results The default is 0 15 00 WET_STEPis the time step length used to compute runoff from subcatchments during periods of rainfall or when ponded water still remains on the surface The default is 0 05 00 DRY_STEP is the time step length used for runoff computations consisting essentially of pollutant buildup during periods when there is no rainfall and no ponded water The default is 1 00 00 ROUTING_STEP is the time step length in seconds used for routing flows and water quality constituents through the conveyance system The default is 600 sec 5 minutes which should be reduced if using dynamic wave routing Fractional values e g 2 5 are permissible as are values entered in hours minutes seconds format LENGTHENING_STEP is a time step in seconds used to lengthen conduits under dynamic wave routing so that they meet the Courant stability criterion under full flow conditions 1 e the travel time of a wave will not be
89. a dynamic rainfall runoff simulation model used for single event or long term continuous simulation of runoff quantity and quality from primarily urban areas The runoff component of SWMM operates on a collection of subcatchment areas that receive precipitation and generate runoff and pollutant loads The routing portion of SWMM transports this runoff through a system of pipes channels storage treatment devices pumps and regulators SWMM tracks the quantity and quality of runoff generated within each subcatchment and the flow rate flow depth and quality of water in each pipe and channel during a simulation period comprised of multiple time steps SWMM was first developed in 1971 and has undergone several major upgrades since then It continues to be widely used throughout the world for planning analysis and design related to storm water runoff combined sewers sanitary sewers and other drainage systems in urban areas with many applications in non urban areas as well The current edition Version 5 is a complete re write of the previous release Running under Windows SWMM 5 provides an integrated environment for editing study area input data running hydrologic hydraulic and water quality simulations and viewing the results in a variety of formats These include color coded drainage area and conveyance system maps time series graphs and tables profile plots and statistical frequency analyses This latest re write of SWMM was produce
90. a new transect object is created or an existing transect is selected for editing It contains the following data entry fields Transect Editor Transect Hame Desorption Left Bank Right Bank Channel Bank Stations CY Ald Stations 0 0 Elevations 799 Name The name assigned to the transect Description An optional comment or description of the transect Station Elevation Data Grid Values of distance from the left side of the channel along with the corresponding elevation of the channel bottom as one moves across the channel from left to right looking in the downstream direction Up to 1500 data values can be entered Roughness Values of Manning s roughness for the left overbank right overbank and main channel portion of the transect The overbank roughness values can be zero if no overbank exists Bank Stations The distance values appearing in the Station Elevation grid that mark the end of the left overbank and the start of the right overbank Use O to denote the absence of an overbank 204 Modifiers The Stations modifier is a factor by which the distance between each station will be multiplied when the transect data is processed by SWMM Use a value of 0 if no such factor is needed The Elevations modifier is a constant value that will be added to each elevation value Right clicking over the Data Grid will make a popup Edit menu appear It contains commands to cut copy insert and paste selected cells in t
91. a node of the drainage system These inflows are represented by both a constant and time varying component as follows Inflow at time t baseline value scale factor time series value at time t The dialog consists of the following input fields Inflows for Node 82309 Direct Dry Weather RADII Constituent Baseline fe Time Series Scale Factor 1 0 NOTE Leave Baseline and Time Seres telde blank to remove any direct inflow for a green constituent at this node Constituent Selects the constituent FLOW or one of the project s specified pollutants whose direct inflow will be described 188 Baseline Specifies the value of the constant baseline component of the constituent s inflow For FLOW the units are the project s flow units For pollutants the units are the pollutant s concentration units if inflow is a concentration or can be any mass flow units if the inflow is a mass flow see Conversion Factor below If left blank then no baseline inflow is assumed Time Series Specifies the name of the time series that contains inflow data for the selected constituent If left blank then no direct inflow will occur for the selected constituent at the node in question You can click the Z button to bring up the Time Series Editor dialog for the selected time series Scale Factor A multiplier used to adjust the values of the constituent s inflow time series The baseline value is not adjusted by this factor
92. able in Section A 2 Curve Number Infiltration Parameters The following data fields appear in the Infiltration Editor for Curve Number infiltration Curve Number This is the SCS curve number which is tabulated in the publication SCS Urban Hydrology for Small Watersheds 2nd Ed TR 55 June 1986 Consult the Curve Number Table Section A 4 for a listing of values by soil group and the accompanying Soil Group Table Section A 3 for the definitions of the various groups Conductivity The soil s saturated hydraulic conductivity in hr or mm hr Typical ranges are shown in both the Soil Group Table Section A 3 and in the Soil Characteristics Table Section A 2 This is used to estimate the minimum number of dry hours that must occur before a new storm is considered to begin using the equation dry hours 4 5 conductivity in hr 1 2 Drying Time The number of days it takes a fully saturated soil to dry Typical values range between 2 and 14 days 187 C 8 Inflows Editor The Inflows Editor dialog is used to assign Direct Dry Weather and RDI inflow into a node of the drainage system It is invoked whenever the Inflows property of a Node object is selected in the Property Editor The dialog consists of three tabbed pages that provide a special editor for each type of inflow Direct Inflows Page The Direct page on the Inflows Editor dialog is used to specify the time history of direct external flow and water quality entering
93. action Last Cleaned User assigned name of the pollutant User assigned name of land use Figure 2 17 Pollutant Editor dialog Figure 2 18 Land Use Editor dialog Next we need to define buildup and washoff functions for TSS in each of our land use categories Functions for Lead are not needed since its runoff concentration was defined to be a fixed fraction of the TSS concentration Normally defining these functions requires site specific calibration In this example we will assume that suspended solids in Residential areas builds up at a constant rate of 1 pound per acre per day until a limit of 50 lbs per acre is reached For the Undeveloped area we will assume that buildup is only half as much For the washoff function we will assume a constant event mean concentration of 100 mg L for Residential land and 50 mg L for Undeveloped land When runoff occurs these concentrations will be maintained until the avaliable buildup is exhausted To define these functions for the Residential land use 1 Select the Residential land use category from the Data Browser and click the 4 button 2 Inthe Land Use Editor dialog move to the Buildup page see Figure 2 19 3 Select TSS as the pollutant and POW for Power function as the function type 26 6 Assign the function a maximum buildup of 50 a rate constant of 1 0 a power of 1 and select AREA as the normalizer Move to the Washoff page of the dialog and select TSS
94. adjustment factors AL HOURLY 0 5 0 6 0 7 0 8 0 8 0 9 H1 Lel dee deo Lee Let 220 H1 O 9 Des 0 7 0 6 25 0 5 H1 Ceo Uae Wao Uso Des 6 Section INFLOWS Purpose Specifies external hydrographs and pollutographs that enter the drainage system at specific nodes Formats Node FLOW FlowSeries Node Pollut PollSeries Format CONVFaACEOr Remarks Node name of node where external inflow enters FlowSeries name of time series in TIMESERIES section describing how external inflows vary with time Pollur name of pollutant PollSeries name of time series describing how external pollutant loading varies with time Format CONCEN if pollutant inflow is described as a concentration MASS if it is described as a mass flow rate ConvFactor the factor that converts the inflow s mass flow rate units into the project s mass units per second where the project s mass units are those specified for the pollutant in the POLLUTANTS section see example below If an external inflow of a pollutant concentration is specified for a node then there must also be an external inflow of FLOW provided for the same node Examples NODE2 FLOW N2FLOW NODE33 Too N33TSS CONCEN Mass inflow of BOD in time series N65BOD given in lbs hr 126 converts lbs hr to mg sec NODE65 BOD N65BOD MASS 126 244 Section LOADINGS Purpose Specifies the pollutant buildup that exists on each subcatchment at the start of a simulation Format Subcat Po
95. age description presence of a flap gate to prevent backflow through the outfall 3 2 5 Flow Divider Nodes Flow Dividers are drainage system nodes that divert inflows to a specific conduit in a prescribed manner A flow divider can have no more than two conduit links on its discharge side Flow dividers are only active under Kinematic Wave routing and are treated as simple junctions under Dynamic Wave routing There are four types of flow dividers defined by the manner in which inflows are diverted Cutoff Divider diverts all inflow above a defined cutoff value Overflow Divider diverts all inflow above the flow capacity of the non diverted conduit Tabular Divider uses a table that expresses diverted flow as a function of total inflow Weir Divider uses a weir equation to compute diverted flow The flow diverted through a weir divider is computed by the following equation Q S E T where Qj diverted flow Cu weir coefficient H weir height and fis computed as Q Q d E z Q min where U is the inflow to the divider Qmin 18 the flow at which diversion begins and _ 1 5 Org Oe The user specified parameters for the weir divider are Qmin Hw and Cy 36 The principal input parameters for a flow divider are junction parameters see above name of the link receiving the diverted flow method used for computing the amount of diverted flow 3 2 6 Storage Units Storage Units are drainage system nod
96. ain water concentration units GW Concentration Concentration of the pollutant in ground water concentration units I amp I Concentration Concentration of the pollutant in any Infiltration Inflow concentration units Decay Coefficient First order decay coefficient of the pollutant 1 days Snow Only YES if pollutant buildup occurs only when snowfall occurs NO otherwise default is NO 197 Co Pollutant Name of another pollutant whose runoff concentration contributes to the runoff concentration of the current pollutant Co Fraction Fraction of the co pollutant s runoff concentration that contributes to the runoff concentration of the current pollutant An example of a co pollutant relationship would be where the runoff concentration of a particular heavy metal is some fixed fraction of the runoff concentration of suspended solids In this case suspended solids would be declared as the co pollutant for the heavy metal C13 Snow Pack Editor The Snow Pack Editor is invoked when a new snow pack object is created or an existing snow pack is selected for editing The editor contains a data entry field for the snow pack s name and two tabbed pages one for snow pack parameters and one for snow removal parameters Snow Pack Parameters Page Snow Pack Editor Snow Pack Name snow Pack Parameters Show Removal Parameters Fraction of Impervious Area That 12 Plowable 05 198 The Parameters page of the S
97. ainfall data to it Each unit hydrograph as shown in Figure 3 3 is defined by three parameters 45 R the fraction of rainfall volume that enters the sewer system T the time from the onset of rainfall to the peak of the UH in hours K the ratio of time to recession of the UH to the time to peak reak T Ti HEJ Time Figure 3 3 An RDII unit hydrograph A UH group can also have a set of Initial Abstraction IA parameters associated with it These determine how much rainfall is lost to interception and depression storage before any excess rainfall 19 generated and transformed into RDII flow by a unit hydrograph The IA parameters consist of a maximum possible depth of IA inches or mm arecovery rate inches day or mm day at which stored IA is depleted during dry periods an initial depth of stored IA inches or mm To generate RDI into a drainage system node the node must identify through its Inflows property the UH group and the area of the surrounding sewershed that contributes RDII flow Y An alternative to using unit hydrographs to define RDI flow is to create an external RDI interface file which contains RDII time series data 3 3 5 Transects Transects refer to the geometric data that describe how bottom elevation varies with horizontal distance over the cross section of a natural channel or irregular shaped conduit Figure 3 4 displays an example transect for a natural channel 46 Y Oyerbank C
98. ale and viewing area will change as the map window is zoomed and panned For this reason metafiles work better than bitmaps or JPEGs since they will not loose resolution when re scaled Most CAD and GIS programs have the ability to save their drawings and maps as metafiles Selecting View gt gt Backdrop from the Main Menu will display a sub menu with the following commands Load loads a backdrop image file into the project Unload unloads the backdrop image from the project Align aligns the drainage system schematic with the backdrop Resize resizes the map dimensions of the backdrop Watermark toggles the backdrop image appearance between normal and lightened To load a backdrop image select View gt gt Backdrop gt gt Load from the Main Menu A Backdrop Image Selector dialog form will be displayed The entries on this form are as follows Backdrop Image Selector Backdrop Image File World Coordinates File optional Scale Map to Backdrop Image Backdrop Image File Enter the name of the file that contains the image You can click the 4 button to bring up a standard Windows file selection dialog from which you can search for the image file World Coordinates File If a world file exists for the image enter its name here or click the E button to search for it A world file contains geo referencing information for the image and can be created from the software that produced the image file o
99. all three hydrographs be defined The shape parameters for each UH consist of R the fraction of rainfall volume that enters the sewer system T the time from the onset of rainfall to the peak of the UH in hours K the ratio of time to recession of the UH to the time to peak Initial Abstraction Parameters Grid This data grid contains parameters that define how rainfall will be reduced by any available initial abstraction 1 e interception and depression storage before it is processed through the unit hydrographs defined for a specific month of the year These parameters consist of the maximum depth of initial abstraction available in rain depth units the rate at which any utilized initial abstraction is made available again in rain depth units per day the amount of initial abstraction that has already been utilized at the start of the simulation in rain depth units If a grid cell is left empty its corresponding parameter value is assumed to be Q Right clicking over the R T K data grid will make a popup Edit menu appear It contains commands to cut copy and paste text to or from selected cells in the grid 207 This page intentionally left blank 208 APPENDIX D COMMAND LINE SWMM D 1 General Instructions EPA SWMM can also be run as a console application from the command line within a DOS window In this case the study area data are placed into a text file and results are written to a text file The
100. alogs to specify what information the table should contain The Table by Object dialog is used when creating a time series table of several variables for a single object Use the dialog as follows 128 aA W N a 6 Table by Object Start Date End Date 01701 1398 w 01702 1998 kd Time Format Object Category Warlablez Links Flow dl Depth Velocity Froude Mo Capacity T55 Lead Cancel Select a Start Date and End Date for the table the default is the entire simulation period Choose whether to show time as Elapsed Time or as Date Time values Choose an Object Category Subcatchment Node Link or System Identify a specific object in the category by o the object either on the Study Area Map or in the Data Browser and then clicking the button on the dialog Only a single object can be selected for this type of table Check off the variables to be tabulated for the selected object The available choices depend on the category of object selected Click the OK button to create the table The Table by Variable dialog 1s used when creating a time series table of a single variable for one or more objects Use the dialog as follows E 2 cF 4 Select a Start Date and End Date for the table the default is the entire simulation period Choose whether to show time as Elapsed Time or as Date Time values Choose an Object Category Subcatchment Node or Link Select a simulated variable to be tab
101. and data can be added to the SWMM project file using any text editor or spreadsheet program SWMM s map data are organized into the following seven sections SWMM does not provide any automated facility formats into the SWMM map data format D3 CN BD ADD HS DDR MVD eye yey wwe ae SO A A KN N NN N N ESOS NN aac POV Veer NN OOO NA Figure D 2 Example study area map 249 MAP DIMENSIONS Dis OO 0 00 10000 00 10000 00 UNITS None COORDINATES Node N1 N2 N3 N4 VERTICES Link 3 3 SYMBOLS Gage G1 X Coorqd 4006 62 6953 64 4635 76 3509 93 X Coord 5430 46 7251 66 X Coord 5298 01 Y Coord 5463 58 4768 21 3443 71 827 81 Y Coord 2019 87 927 15 Y Coord 9139 07 Polygons Subcatchment X Coorqd YC OOT S1 3708 61 8543 05 Sil 4834 44 7019 87 S1 3675 50 4834 44 lt additional vertices not listed gt SZ 6523 18 8079 47 SZ 8112 58 8841 06 LABELS j X Coord 5033 11 1655 63 FILS Y Coorqd Label 8807 95 Gi 7450 33 TST 7549 67 S2 Figure D 3 Data for map shown in Figure D 2 A detailed description of each map data section will now be given Remember that map data are only used as a visualization aid for SWMM s GUI and they play no role in any of the runoff or routing computations Map data are not needed for running the command line version of SWMM 250 Section MAP Purpose Provides dimensions and distance units for the map
102. ature of the pack is increased by the equivalent heat content of the melted snow up to the base melt temperature Any remaining melt liquid beyond this is available to runoff from the pack 7 The available snowmelt is then reduced by the amount of free water holding capacity remaining in the pack The remaining melt is treated the same as an additional rainfall input onto the subcatchment 3 4 5 Flow Routing Flow routing within a conduit link in SWMM is governed by the conservation of mass and momentum equations for gradually varied unsteady flow 1 e the Saint Venant flow equations The SWMM user has a choice on the level of sophistication used to solve these equations Steady Flow Routing Kinematic Wave Routing Dynamic Wave Routing Steady Flow Routing Steady Flow routing represents the simplest type of routing possible actually no routing by assuming that within each computational time step flow is uniform and steady Thus it simply translates inflow hydrographs at the upstream end of the conduit to the downstream end with no delay or change in shape The normal flow equation is used to relate flow rate to flow area or depth 56 This type of routing cannot account for channel storage backwater effects entrance exit losses flow reversal or pressurized flow It can only be used with dendritic conveyance networks where each node has only a single outflow link unless the node is a divider in which case two outflow
103. between 60 and 60 degrees invalid parameters for Snow Pack xxx A snow pack s minimum melt coefficient is greater than its maximum coefficient the fractions of free water capacity or impervious plowable area are not between U and 1 or the snow removal fractions sum to more than 1 0 simulation start date comes after ending date Self explanatory report start date comes after ending date Self explanatory reporting time step is less than routing time step Self explanatory one or more errors in input file This message appears when one or more input file parsing errors the 200 series errors occur too many characters in input line A line in the input file cannot exceed 1024 characters too few items at line n of input file Not enough data items were supplied on a line of the input file invalid keyword at line n of input file An unrecognized keyword was encountered when parsing a line of the input file 257 ERROR 207 ERROR 209 ERROR 211 ERROR 213 ERROR 217 ERROR 219 ERROR 221 ERROR 223 ERROR 225 ERROR 227 ERROR 229 ERROR 231 ERROR 233 duplicate ID name at line n of input file An ID name used for an object was already assigned to an object of the same category undefined object xxx at line n of input file A reference was made to an object that was never defined An example would be if node 123 were designated as the outlet point of a subcatchment yet no such
104. bject appear on the map and is therefore recommended With the second method the object will not appear on the map until X Y coordinates are entered manually by editing the object s properties What follows are more specific instructions for adding each type of object to a project Adding a Rain Gage To add a Rain Gage using the Object Toolbar 1 Click on the toolbar 2 Move the mouse to the desired location on the map and click To add a Rain Gage using the Data Browser 1 Select Rain Gages from the list of categories 81 2 Click the Y button 3 Enter the rain gage s X and Y coordinates in the Property Editor if you want it to appear on the study area map Adding a Subcatchment To add a Subcatchment using the Object Toolbar Click ES on the toolbar Use the mouse to draw a polygon outline of the subcatchment on the map 1 2 3 left click at each vertex 4 right click or press lt Enter gt to close the polygon 5 press the lt Esc gt key if you wish to cancel the action To add a Subcatchment using the Data Browser 1 Select Subcatchments from the list of object categories 2 Click the button 3 Enter the X and Y coordinates of the subcatchment s centroid in the Property Editor if you want it to appear on the study area map Adding a Node To add a Node using the Object Toolbar 1 Click the button for the type of node to add 1f 1ts not already depressed L fora junction Y f
105. bjects on the map is just one way of creating a project For large projects it might be more convenient to first construct a SWMM project file external to the program The project file is a text file that describes each object in a specified format as described in Appendix D of this manual Data extracted from various sources such as CAD drawings or GIS files can be used to create the project file 10 2 Move the mouse to the map location where one of the corners of subcatchment S lies and left click the mouse 3 Do the same for the next three corners and then right click the mouse or hit the Enter key to close up the rectangle that represents subcatchment S You can press the Esc key if instead you wanted to cancel your partially drawn subcatchment and start over again Don t worry if the shape or position of the object isn t quite right We will go back later and show how to fix this 4 Repeat this process for subcatchments 2 and S3 Observe how sequential ID labels are generated automatically as we add objects to the map Next we will add in the junction nodes and the outfall node that comprise part of the drainage network 1 To begin adding junctions click the button on the Object Toolbar 2 Move the mouse to the position of junction J and left click it Do the same for junctions J2 through J4 3 To add the outfall node click the button on the Object Toolbar move the mouse to the outfall s location on the map and left
106. by selecting View gt gt Backdrop gt gt Resize In this case the following Backdrop Dimensions dialog will appear Backdrop Dimensions Lower Lett Backdrop coordinate 2665029 39 coordinate 213004 04 Upper Right Backdrop coordinate 2r 21645 73 0000 00 coordinate 297152 2P 10000 00 Resize Backdrop Image Only Scale Backdrop Image to Map Scale Map to Backdrop Image The dialog lets you manually enter the X Y coordinates of the backdrop s lower left and upper right corners The Study Area Map s dimensions are also displayed for reference While the dialog is visible you can view map coordinates by moving the mouse over the map window and noting the X Y values displayed in SW NMM S Status Panel at the bottom of the main window 92 Selecting the Resize Backdrop Image Only button will resize only the backdrop and not the Study Area Map according to the coordinates specified Selecting the Scale Backdrop Image to Map button will position the backdrop image in the center of the Study Area Map and have it resized to fill the display window without changing its aspect ratio The map s lower left and upper right coordinates will be placed in the data entry fields for the backdrop coordinates and these fields will become disabled Selecting Scale Map to Backdrop Image makes the dimensions of the map coincide with the dimensions being set for the backdrop image Note that this option will chang
107. c Study roa Map CIA DLL 251 d a 1 E L b B 11 i 13 14 13 16 Io Lei OT me ons pE Te ESD 59 4 2 Main Menu The Main Menu located across the top of the EPA SWMM main window contains a collection of menus used to control the program These include File Menu Edit Menu View Menu Project Menu Report Menu Tools Menu Window Menu Help Menu File Menu The File Menu contains commands for opening and saving data files and for printing Command New Open Reopen Save Save As Export Combine Page Setup Print Preview Print Exit Description Creates anew SWMM project Opens an existing project Reopens a recently used project Saves the current project Saves the current project under a different name Exports study area map to a file in a variety of formats Exports current results to a Hot Start file Combines two Routing Interface files together Sets page margins and orientation for printing Previews a printout of the currently active view map report graph or table Prints the current view Exits EPA SWMM 60 Edit Menu The Edit Menu contains commands for editing and copying Command Copy To Select Object Select Vertex Select Region Select All Find Object Find Text Group Edit Group Delete View Menu Description Copies the currently active view map report graph or table to the clipboard or to a file Enables the user t
108. cations that users can add to the Tools menu of the main SWMM menu bar and be launched while SWMM is still running SWMM can interact with these applications to a limited degree by exchanging data through its pre defined files see Chapter 11 or through the Windows clipboard Add in tools can provide additional modeling capabilities to what SWMM already offers Some examples of useful add ins might include a tool that performs a statistical analysis of long term rainfall data prior to adding it to a SWMM rain gage an external spreadsheet program that would facilitate the editing of a SWMM data set a unit hydrograph estimator program that would derive the R T K parameters for a set of RDI unit hydrographs which could then be copied and pasted directly into SWMM s Unit Hydrograph Editor 4 post processor program that uses SWMM s hydraulic results to compute suspended solids removal through a storage unit a third party dynamic flow routing program used as a substitute for SWMM s own internal procedure Figure 12 1 shows what the Tools menu might look like after several add in tools have been registered with it The Configure Tools option is used to add delete or modify add in tools The options below this are the individual tools that have been made available by this particular user and can be launched by selecting them from the menu File Edit View Project Report Tools Window Help O g amp h 22 3 Program Preferenc
109. ch pollutant separately from the Pollutant dropdown list and specify its pertinent buildup properties Washoff Page The Washoff page of the Land Use Editor dialog describes the properties associated with pollutant washoff over the land use during wet weather events These consist of Land Use Editor General Buildup Washot Pollutant T55 Property Value Function EsP Coefficient 0 1 Exponent 1 Cleaning Effic U BMP Eftic U Weashoff function EXP exponential AC rating curve EMC event mean concentration Pollutant The name of the pollutant whose washoff properties are being edited Function The choice of washoff function to use for the pollutant The choices are NONE no washoff EXP exponential washoff RC rating curve washoff EMC event mean concentration washoff The formula for each of these functions is discussed in Section 3 3 9 under the Pollutant Washoff topic Coefficient This is the value of Cl in the exponential and rating curve formulas or the event mean concentration 195 Exponent The exponent used in the exponential and rating curve washoff formulas Cleaning Efficiency The street cleaning removal efficiency percent for the pollutant It represents the fraction of the amount that is available for removal on the land use as a whole set on the General page of the editor which is actually removed BMP Efficiency Removal efficiency percent associated with any Best Managem
110. coincides with the first point then the area of the enclosed polygon will also be displayed 7 5 Zooming the Map To Zoom In on the Study Area Map 1 Select View gt gt Zoom In from the Main Menu or click 4 on the Map Toolbar 93 2 To zoom in 100 1 e 2X move the mouse to the center of the zoom area and click the left button 3 To perform a custom zoom move the mouse to the upper left corner of the zoom area and with the left button pressed down draw a rectangular outline around the zoom area Then release the left button To Zoom Out on the Study Area Map 1 Select View gt gt Zoom Out from the Main Menu or click 4 on the Map Toolbar 2 The map will be returned to the view in effect at the previous zoom level 7 6 Panning the Map To pan across the Study Area Map window 1 Select View gt gt Pan from the Main Menu or click on the Map Toolbar 2 With the left button held down over any point on the map drag the mouse in the direction you wish to pan in 3 Release the mouse button to complete the pan To pan using the Overview Map which is described in Section 7 10 below 1 If not already visible bring up the Overview Map by selecting View gt gt Overview Map from the Main Menu 2 If the Study Area Map has been zoomed in an outline of the current viewing area will appear on the Overview Map Position the mouse within this outline on the Overview Map 3 With the left button held down
111. command line for running SWMM in this fashion is swmm5 inpfile rptfile outfile where inpfile is the name of the input file rptfile is the name of the output report file and outfile is the name of an optional binary output file that stores results in a special binary format If the latter file is not needed then just the input and report file names should be supplied As written the above command assumes that you are working in the directory in which EPA SWMM was installed or that this directory has been added to the PATH variable in your user profile or the autoexec bat file in older versions of Windows Otherwise full pathnames for the executable swmm5 exe and the files on the command line must be used D 2 Input File Format The input file for command line SWMM has the same format as the project file used by the Windows version of the program Figure D 1 illustrates an example SWMM5 input file It is organized in sections where each section begins with a keyword enclosed in brackets The various keywords are listed below TITLE project title OPTIONS analysis options REPORT output reporting instructions FILES interface file options RAINGAGES rain gage information HYDROGRAPHS unit hydrograph data used to construct RDI inflows EVAPORATION evaporation data TEMPERATURE air temperature and snow melt data SUBCATCHMENTS basic subcatchment information SUBAREAS subcatchment impervious pervious sub area data INFILT
112. cription Mo dates means times are relative to start of simulation Figure 2 7 Time Series Editor dialog The Time Series Editor can also be launched directly from the Rain Gage Property Editor by selecting the editor s Series Name field and double clicking on it Leaving off the dates for a time series means that SWMM will interpret the time values as hours from the start of the simulation Otherwise the time series follows the date time values specified by the user 15 Having completed the initial design of our example project it is a good idea to give it a title and save our work to a file at this point To do this 1 Select the Title Notes category from the Data Browser and click the 4 button 2 In the Project Title Notes dialog that appears see Figure 2 8 enter Tutorial Example as the title of our project and click the OK button to close the dialog 3 From the File menu select the Save As option 4 In the Save As dialog that appears select a folder and file name under which to save this project We suggest naming the file tutorial inp An extension of inp will be added to the file name if one is not supplied 5 Click Save to save the project to file The project data are saved to the file in a readable text format You can view what the file looks like by selecting Project gt gt Details from the main menu To open our project at some later time you would select the Open command from the File me
113. cted vertex will be displayed as a filled square To select a particular vertex click the mouse over it 3 To add a new vertex to the link right click the mouse and select Add Vertex from the popup menu or simply press the lt Insert gt key on the keyboard 4 To delete the currently selected vertex right click the mouse and select Delete Vertex from the popup menu or simply press the lt Delete gt key on the keyboard 5 To move a vertex to another location drag it to its new position with the left mouse button held down While in Vertex Selection mode you can begin editing the vertices for another link by simply clicking on the link To leave Vertex Selection mode right click on the map and select Quit Editing from the popup menu or simply select one of the other buttons on the Map Toolbar A link can also have its direction reversed 1 e its end nodes switched by right clicking on it and selecting Reverse from the pop up menu that appears Normally links should be oriented so that the upstream end is at a higher elevation than the downstream end 6 8 Shaping a Subcatchment Subcatchments are drawn on the Study Area Map as closed polygons To edit or add vertices to the polygon follow the same procedures used for links If the subcatchment 19 originally drawn or is edited to have two or less vertices then only its centroid symbol will be displayed on the Study Area Map 6 9 Deleting an Object To delete an object 1
114. ctive window in the SWMM workspace This can include the study area map a graph a table or a report 10 1 Selecting a Printer To select a printer from among your installed Windows printers and set its properties s H 2 3 Select File gt gt Page Setup from the Main Menu Click the Printer button on the Page Setup dialog that appears see Figure 10 1 Select a printer from the choices available in the combo box in the Print Setup dialog that appears Click the Properties button to select the appropriate printer properties which vary with choice of printer Click OK on each dialog to accept your selections Page Setup Margins Headers Footers Paper Size width 8 5 Height 11 0 Orientation Margins inches 2 Portrait Left ioo Right Landscape Top 4 Bottom Figure 10 1 The Margins page of the Page Setup dialog 135 10 2 Setting the Page Format To format the printed page 1 2 3 4 5 6 7 9 Select File gt gt Page Setup from the main menu Use the Margins page of the Page Setup dialog form that appears Figure 10 1 to Select a printer Select the paper orientation Portrait or Landscape Set left right top and bottom margins Use the Headers Footers page of the dialog box Figure 10 2 to Supply the text for a header that will appear on each page Indicate whether the header should be printed or not and how its text should be aligned
115. d 1602 O OSLO Dis 20 O OF 30 Joro O LOO O O helo Gogi 11 6 Time Series Files Time series files are external text files that contain data for SWMM s time series objects Examples of time series data include rainfall evaporation inflows to nodes of the drainage system and water stage at outfall boundary nodes Normally these data are entered and edited through SWMM s Time Series Editor However there is an option to import data from an external file into the editor Creating and editing this file can be done outside of SWMM using text editors or spreadsheet programs The format of a time series file consists of two lines of descriptive text followed by the actual tme series data with one time series value per line Typically the first text line identifies the tme series and the second line includes a detailed description of the time series Time series values can either be in date time value format or in time value format where each entry is separated by one or more spaces or tab characters For the date time value format dates are entered as month day year e g 7 21 2004 and times as 24 hour military time e g 8 30 pm is 20 30 After the first date additional dates need only be entered whenever a new day occurs For the time value format time can either be decimal hours or military time since the start of a simulation e g 2 days 4 hours and 20 minutes can be entered as either 52 333 or 52 20 An example of a tim
116. d by moving the crest height up or down for Outlets it is a multiplier applied to the flow computed from the outlet s rating curve Some examples of action clauses are PUMP P67 STATUS OFF ORIP ICE O22 SETTING Des Modulated Controls Modulated controls are control rules that provide for a continuous degree of control applied to a pump or flow regulator as determined by the value of some controller variable such as water depth at a node or by time The functional relation between the control setting and the controller variable can be specified by using a Control Curve a Time Series or a PID Controller Some examples of modulated control rules are RULE MC1 IF NODE N2 DEPTH gt 0 THEN WEIR W25 SETTING CURVE C25 RULE MC2 IF SIMULATION TIME gt 0 THEN PUMP P12 SETTING TIMESERIES TS101 RULE MC3 LE BLINK LS ELOW lt gt Leo THEN ORDPICE QOL2Z SETTING PID 01 040 0x0 Note how a modified form of the action clause is used to specify the name of the control curve time series or PID parameter set that defines the degree of control A PID parameter set contains three values a proportional gain coefficient an integral time in minutes and a derivative time in minutes Also by convention the controller variable used in a Control Curve or PID Controller will always be the object and attribute named in the last condition clause of the rule As an example in rule MC1 above Curve C25 would define how the fractional se
117. d by the Water Supply and Water Resources Division of the U S Environmental Protection Agency s National Risk Management Research Laboratory with assistance from the consulting firm of CDM Inc 1 2 Modeling Capabilities SWMM accounts for various hydrologic processes that produce runoff from urban areas These include time varying rainfall evaporation of standing surface water SHOW accumulation and melting rainfall interception from depression storage infiltration of rainfall into unsaturated soil layers percolation of infiltrated water into groundwater layers interflow between groundwater and the drainage system nonlinear reservoir routing of overland flow Metcalf amp Eddy Inc University of Florida Water Resources Engineers Inc Storm Water Management Model Volume I Final Report 11024DOC07 71 Water Quality Office Environmental Protection Agency Washington DC July 1971 7 Huber W C and Dickinson R E Storm Water Management Model Version 4 User s Manual EPA 600 3 88 001a Environmental Research Laboratory U S Environmental Protection Agency Athens GA October 1992 Spatial variability in all of these processes is achieved by dividing a study area into a collection of smaller homogeneous subcatchment areas each containing its own fraction of pervious and impervious sub areas Overland flow can be routed between sub areas between subcatchments or between entry points of a
118. de Name of node on the inlet end of the conduit which is normally the end at higher elevation Outlet Node Name of node on the outlet end of the conduit which is normally the end at lower elevation Description Click the ellipsis button or press Enter to edit an optional description of the conduit Tag Optional label used to categorize or classify the conduit Shape Click the ellipsis button or press Enter to edit the geometric eee of the conduit s cross section Max Max Depth Maximum Maximum depth of the conduit s cross section feet or meters of the conduit s cross section feet or meters Length Length Conduit length feet or meters Conduit length feet or meters Roughness Manning s roughness coefficient see Section A 7 for closed conduit values or Section A 8 for open channel values Inlet Offset Depth or elevation of the conduit invert above the node invert at the upstream end of the conduit feet or meters Outlet Offset Depth or elevation of the conduit invert above the node invert at the downstream end of the conduit feet or meters Initial Flow Initial flow in the conduit flow units Maximum Flow Maximum flow allowed in the conduit flow units use O or leave blank if not applicable Entry Loss Coeff Head loss coefficient associated with energy losses at the entrance of the conduit Exit Loss Coeff Head loss coefficient associated with energy losses at the exit of
119. der e l Conduits Selections made in the Data Browser are coordinated with objects highlighted on the Study Area Map and vice versa For example selecting a conduit in the Data Browser will cause that conduit to be highlighted on the map while selecting it on the map will cause it to become the selected object in the Data Browser 4 7 Map Browser The Map Browser panel shown below appears when the Map tab on the left panel of the SWMM workspace is selected It controls the mapping themes and time periods viewed on the Study Area Map The width of the Map Browser panel can be adjusted by using the splitter bar located along its right edge 67 Data Map Themez Subcatchments Area e Nodes Invert X Links Max Depth Time Period Date 01 01 19 l 4 TT The Map Browser consists of the following three panels that control what results are displayed on the map The Themes panel selects a set of variables to view in color coded fashion on the Map The Time Period panel selects which time period of the simulation results are viewed on the Map The Animator panel controls the animated display of the Study Area Map and all Profile Plots over time The width of the Map Browser panel can be adjusted by using the splitter bar located along its right edge The Themes panel of the Map Browser is used to select a thematic variable to view in color coded fashion on the Study Area Map Themez S
120. des and Links from the dropdown combo boxes appearing in the Themes panel In Figure 2 11 subcatchment runoff and link flow have been selected for viewing The color coding used for a particular variable is displayed with a legend on the study area map To toggle the display of a legend select View gt gt Legends To move a legend to another location drag 1t with the left mouse button held down To change the color coding and the breakpoint values for different colors select View gt gt Legends gt gt Modify and then the pertinent class of object or if the legend is already visible simply right click on it To view numerical values for the variables being displayed on the map select Tools gt gt Map Display Options and then select the Annotation page of the Map Options dialog Use the check boxes for Subcatchment Values Node Values and Link Values to specify what kind of annotation to add The Date Time of Day Elapsed Time controls on the Map Browser can be used to move through the simulation results in time Figure 2 11 depicts results at 5 hours and 45 minutes into the simulation You can use the controls in the Animator panel of the Map Browser see Figure 2 11 to animate the map display through time For example pressing the button will run the animation forward in time Viewing a Time Series Plot To generate a time series plot of a simulation result E 2 Select Report gt gt Graph gt gt Tim
121. dows except for the study area map Window List Lists all open windows the currently selected window has the focus and is denoted with a check mark Help Menu The Help Menu contains commands for getting help in using EPA SWMM Command Description Help Topics Displays the Help system s Table of Contents How Do I Displays a list of topics covering the most common operations Measurement Units Shows measurement units for all of SWMM s parameters Error Messages Lists the meaning of all error messages Tutorial Presents a short tutorial introducing the user to EPA SWMM About Lists information about the version of EPA SWMM being used 4 3 Toolbars Toolbars provide shortcuts to commonly used operations There are three such toolbars Standard Toolbar Map Toolbar Object Toolbar All toolbars can be docked underneath the Main Menu bar docked on the right side of the Browser Panel or dragged to any location on the EPA SWMM workspace When undocked they can also be re sized Toolbars can be made visible or invisible by selecting View gt gt Toolbars from the Main Menu 63 Standard Toolbar The Standard Toolbar contains buttons for the following commonly used commands Creates a new project File gt gt New Opens an existing project File gt gt Open Saves the current project File gt gt Save Prints the currently active window File gt gt Print Copies selection to the clipboard or to a file Edit gt g
122. drag the outline to a new position 4 Release the mouse button and the Study Area Map will be panned to an area corresponding to the outline on the Overview Map 7 7 Viewing at Full Extent To view the Study Area Map at full extent either select View gt gt Full Extent from the Main Menu or press DL on the Map Toolbar 94 7 8 Finding an Object To find an object on the Study Area Map whose name is MAA known 1 Select View gt gt Find Object from the Main Menu or click dn on the Standard Toolbar Adjacent Links 2 In the Map Finder dialog that appears select the type of object to find and enter its name 3 Click the Go button If the object exists it will be highlighted on the map and in the Data Browser If the map is currently zoomed in and the object falls outside the current map boundaries the map will be panned so that the object comes into view Y User assigned object names in SWMM are not case sensitive E g NODEI23 is equivalent to Node123 After an object is found the Map Finder dialog will also list the outlet connections for a subcatchment the connecting links for a node the connecting nodes for a link 7 9 Submitting a Map Query A Map Query identifies objects on the study area map that meet a specific criterion e g nodes which flood links with velocity below 2 ft sec etc To submit a map query 1 Select a time period in which to query the map from the Map Browser
123. drainage system SWMM also contains a flexible set of hydraulic modeling capabilities used to route runoff and external inflows through the drainage system network of pipes channels storage treatment units and diversion structures These include the ability to handle networks of unlimited size use a wide variety of standard closed and open conduit shapes as well as natural channels model special elements such as storage treatment units flow dividers pumps weirs and orifices apply external flows and water quality inputs from surface runoff groundwater interflow rainfall dependent infiltration inflow dry weather sanitary flow and user defined inflows utilize either kinematic wave or full dynamic wave flow routing methods model various flow regimes such as backwater surcharging reverse flow and surface ponding apply user defined dynamic control rules to simulate the operation of pumps orifice openings and weir crest levels In addition to modeling the generation and transport of runoff flows SWMM can also estimate the production of pollutant loads associated with this runoff The following processes can be modeled for any number of user defined water quality constituents 1 3 dry weather pollutant buildup over different land uses pollutant washoff from specific land uses during storm events direct contribution of rainfall deposition reduction in dry weather buildup due to street cleaning reduction in washoff load due to
124. dup is a function of the number of preceding dry weather days and can be computed using one of the following functions Power Function Pollutant buildup B accumulates proportionally to time t raised to some power until a maximum limit is achieved B Min C C t where C maximum buildup possible mass per unit of area or curb length C buildup rate constant and C time exponent Exponential Function Buildup follows an exponential growth curve that approaches a maximum limit asymptotically B C l e where C maximum buildup possible mass per unit of area or curb length and Cz buildup rate constant 1 days Saturation Function Buildup begins at a linear rate that continuously declines with time until a saturation value is reached B Ci Citi where C maximum buildup possible mass per unit area or curb length and C half saturation constant days to reach half of the maximum buildup Pollutant Washoff Pollutant washoff from a given land use category occurs during wet weather periods and can be described in one of the following ways Exponential Washoff The washoff load W in units of mass per hour is proportional to the product of runoff raised to some power and to the amount of buildup remaining W C q B 50 where C washoff coefficient C2 washoff exponent q runoff rate per unit area inches hour or mm hour and B pollutant buildup in mass lbs or kg per unit area or curb l
125. e Series or simply click on the Standard Toolbar A Time Series Plot dialog will appear It is used to select the objects and variables to be plotted For our example the Time Series Plot dialog can be used to graph the flow in conduits C and C2 as follows refer to Figure 2 12 L 2 Select Links as the Object Category Select Flow as the Variable to plot Click on conduit C either on the map or in the Data Browser and then click D in the dialog to add it to the list of links plotted Do the same for conduit C2 Press OK to create the plot which should look like the graph in Figure 2 13 19 SWMM 5 tutorial inp File Edit wiew Project Report Tools Window Help F ice Study Area Map Themes Huna Nodes None Links Flows Time Period Date Ob 2 7 2002 ae SID Time of Day 05 45 00 i au 2 Elapsed Time Auto Length Flow Units CFS L oom Level 100 zT 5341 116 444 239 Figure 2 11 Example of viewing color coded results on the Study Area Map 20 Time Series Plot Start Date End Date 062722002 w 06 27 2002 Ww Time Format Object Categor Elapsed Time Na Links V ariabiez B Flow OOOO Depth Velocity _ Froude Ho Capacity Cancel Figure 2 12 Time Series Plot dialog i B Graph Link Flow Link Flow Link LCT Link 2 P LU LL o 2 LL Elapsed Time hours Figure 2 13
126. e a row You can also click the Load button to load in a curve that was previously saved to file or click the Save button to save the current curve s data to a file C 6 Groundwater Flow Editor Groundwater Flow Editor A Aquifer Name Recenving Node surface Elevation Groundwater Flow Coeff Groundwater Flow Espon surface Water Flow Coeff Surface Water Flow Expor surface L4 Interaction Coeff Fited Surface Water Depth Threshold Groundwater Eley Mame of aquifer object that lies below subcatchmert leave blank for no groundwater 183 The Groundwater Flow Editor dialog is invoked when the Groundwater property of a subcatchment is being edited It is used to link a subcatchment to both an aquifer and to a node of the drainage system that exchanges groundwater with the aquifer It also specifies coefficients that determine the rate of groundwater flow between the aquifer and the node These coefficients Al A2 Bl B2 and A3 appear in the following equation that computes groundwater flow as a function of groundwater and surface water heads Q AIH EP A2 H E A3H H where Q groundwater flow cfs per acre or cms per hectare Hoy elevation of groundwater table ft or m Hsw elevation of surface water at receiving node ft or m E threshold groundwater elevation or node invert elevation ft or m The properties listed in the editor are as follows Aquifer Name Name of aquifer object that
127. e and any adjustment factors supplied by the specified patterns If not supplied an adjustment factor defaults to 1 0 Section PATTERNS Purpose Specifies time pattern of dry weather flow or quality in the form of adjustment factors applied as multipliers to baseline values Format Name MONTHLY Factorl Fator gss PFactoriZ Name DAILY Factor PACCO ges FACLO Name HOURLY Factori Pactos asa Paccorz4 Name WEEKEND Fator Pactor ses aClCOorz4 Remarks Name name used to identify the pattern Factorl Factor etc multiplier values The MONTHLY format is used to set monthly pattern factors for dry weather flow constituents The DAILY format is used to set dry weather pattern factors for each day of the week where Sunday 1s day 1 The HOURLY format is used to set dry weather factors for each hour of the of the day starting from midnight If these factors are different for weekend days than for weekday days then the WEEKEND format can be used to specify hourly adjustment factors just for weekends 243 More than one line can be used to enter a pattern s factors by repeating the pattern s name but not the pattern type at the beginning of each additional line The pattern factors are applied as multipliers to any baseline dry weather flows or quality concentrations supplied in the DWF section Examples Day of week adjustment factors Di DALLY Os 10 1220 2 0 2 0 1 0 OVS D2 DAILY Use Uso 220 ded 140 0 9 Uso Hourly
128. e and offers some troubleshooting tips to use when examining simulation results Chapter 9 discusses the various ways in which the results of an analysis can be viewed These include different views of the study area map various kinds of graphs and tables and several different types of special reports Chapter 10 explains how to print and copy the results discussed in Chapter 9 Chapter 11 describes how EPA SWMM can use different types of interface files to make simulations runs more efficient The manual also contains several appendixes Appendix A provides several useful tables of parameter values including a table of units of expression for all design and computed parameters Appendix B lists the editable properties of all visual objects that can be displayed on the study area map and be selected for editing using point and click Appendix C describes the specialized editors available for setting the properties of non visual objects Appendix D provides instructions for running the command line version of SWMM and includes a detailed description of the format of a project file Appendix E lists all of the error messages and their meaning that SWMM can produce This page intentionally left blank CHAPTER 2 QUICK START TUTORIAL This chapter provides a tutorial on how to use EPA SWMM If you are not familiar with the elements that comprise a drainage system and how these are represented ina SWMM model you might
129. e at which pollutant buildup occurs Washoff Page defines rate at which pollutant washoff occurs 192 General Page The General page of the Land Use Editor dialog describes the following properties of a particular land use category Land Use Editor Use Name Residential Description STREET SWEEPING 00 Interval Availability Last Swept User assigned name of land use Land Use Name The name assigned to the land use Description An optional comment or description of the land use click the ellipsis button or press Enter to edit Street Sweeping Interval Days between street sweeping within the land use Street Sweeping Availability Fraction of the buildup of all pollutants that is available for removal by sweeping Last Swept Number of days since last swept at the start of the simulation If street sweeping does not apply to the land use then the last three properties can be left blank Buildup Page The Buildup page of the Land Use Editor dialog describes the properties associated with pollutant buildup over the land during dry weather periods These consist of 193 Land Use Editor General Buildup ww azhar Pollutant T55 Property Value Function Max Buildup Rate Constant Powert5 at Constant Mormalizer Buildup funcion POW power Ex P exponential 547 saturation Pollutant Select the pollutant whose
130. e distance from the invert to the top of the highest connecting link will be used Depth of water at the junction at the start of the simulation feet or meters Initial Depth Surcharge Depth Additional depth of water beyond the maximum depth that is allowed before the junction floods feet or meters This parameter can be used to simulate bolted manhole covers or force main connections Ponded Area Area occupied by ponded water atop the junction after flooding occurs sq feet or sq meters If the Allow Ponding simulation option is turned on a non zero value of this parameter will allow ponded water to be stored and subsequently returned to the conveyance system when capacity exists 163 B 4 Outfall Properties Name User assigned outfall name X Coordinate Horizontal location of the outfall on the Study Area Map If left blank then the outfall will not appear on the map Y Coordinate Vertical location of the outfall on the Study Area Map If left blank then the outfall will not appear on the map Description Click the ellipsis button or press Enter to edit an optional description of the outfall Tag Optional label used to categorize or classify the outfall Inflows Click the ellipsis button or press Enter to assign external direct dry weather or RDII inflows to the outfall Treatment Click the ellipsis button or press Enter to edit a set of treatment functions for a T entering the node I
131. e entered for the conduit which uses the irregular cross section 234 There should be one X1 line for each transect Any number of GR lines may follow and each GR line can have any number of Elevation Station data pairs In HEC 2 the GR line is limited to 5 stations The station that defines the left overbank boundary on the X1 line must correspond to one of the station entries on the GR lines that follow The same holds true for the right overbank boundary If there is no match a warning will be issued and the program will assume that no overbank area exists Section Purpose Formats Remarks CONTROLS Determines how pumps and regulators will be adjusted based on simulation time or conditions at specific nodes and links Each control rule is a series of statements of the form RULE rulelD IF condition 1 AND condition lt OR condition s AND co aition 4 ECC THEN action 1 AND action 2 BEC ELSE action_3 AND action 4 BEC PRIORITY value RuleID an ID label assigned to the rule condition_n a condition clause action_n an action clause value a priority value e g a number from 1 to 5 A condition clause of a Control Rule has the following format Object Name Attribute Relation Value where Object is a category of object Name 1s the object s assigned ID name Attribute is the name of an attribute or property of the object Relationisa relational operator lt gt lt lt gt gt
132. e file xxx An external climate data file could not be opened most likely because it does not exist error in reading from climate file xxx SWMM was trying to read data from an external climate file with the wrong format attempt to read beyond end of climate file xxx The specified external climate does not include data for the period of time being simulated cannot open scratch RDII interface file SWMM could not open the temporary file it uses to store RDII flow data cannot open RDII interface file xxx An RDII interface file could not be opened possibly because it does not exist or because the user does not have write privileges to its directory 260 ERROR 345 ERROR 351 ERROR 353 ERROR 355 ERROR 357 invalid format for RDII interface file SWMM was trying to read data from a designated RDII interface file with the wrong format 1 e it may have been created for some other project or actually be some other type of file cannot open routing interface file xxx A routing interface file could not be opened possibly because it does not exist or because the user does not have write privileges to its directory invalid format for routing interface file xxx SWMM was trying to read data from a designated routing interface file with the wrong format 1 e it may have been created for some other project or actually be some other type of file mismatched names in routing interface file xxx The names of pol
133. e invert discharge coefficient time to open or close Weirs 41 Weirs like orifices are used to model outlet and diversion structures in a drainage system Weirs are typically located in a manhole along the side of a channel or within a storage unit They are internally represented in SWMM as a link connecting two nodes where the weir itself is placed at the upstream node A flap gate can be included to prevent backflow Four varieties of weirs are available each incorporating a different formula for computing flow across the weir as listed in Table 3 2 Table 3 2 Available types of weirs Weir Type Cross Section Shape Flow Formula Trapezoidal Trapezoidal C ROE C shi weir discharge coefficient L weir length S side slope of S A or trapezoidal weir h head difference across the weir Cus discharge coefficient through sides of trapezoidal weir Weirs can be used as storage unit outlets under all types of flow routing If not attached to a storage unit they can only be used in drainage networks that are analyzed with Dynamic Wave flow routing The height of the weir crest above the inlet node invert can be controlled dynamically through user defined Control Rules This feature can be used to model inflatable dams The principal input parameters for a weir include names of its inlet and outlet nodes shape and geometry crest height or elevation above the inlet node invert discharge coeffici
134. e land area units which generate runoff from rainfall Name Rgage OutID Area Imperv Width Slope Clength Spack Name name assigned to subcatchment Rgage name of rain gage in RAINGAGES section assigned to subcatchment Out ID name of node or subcatchment that receives runoff from subcatchment Area area of subcatchment acres or hectares Imperv percent imperviousness of subcatchment Width characteristic width of subcatchment ft or meters Slope subcatchment slope percent Clength total curb length any length units Spack name of snow pack object from SNOWPACKS section that characterizes snow accumulation and melting over the subcatchment Section Purpose Format Remarks SUBAREAS Supplies information about pervious and impervious areas for each subcatchment Each subcatchment can consist of a pervious sub area an impervious sub area with depression storage and an impervious sub area without depression storage Subcat Nimo Nperv Simp Sperv Zero RouteTo Rted Subcat subcatchment name Nimp Mamning s n for overland flow over the impervious sub area Nperv Mamning s n for overland flow over the pervious sub area Simp depression storage for impervious sub area inches or mm Sperv depression storage for pervious sub area inches or mm 3Zero percent of impervious area with no depression storage RouteTo Use IMPERVIOUS if pervious area runoff runs onto impervious area PERVIOUS if impervio
135. e series file is shown below EPASWMM Time Series Data lt optional description goes here gt OIL OL7 2003 100600 000000 OOS 0203200 00 30 0 04800 00 45 0 02400 DESOT 0 01 00 0770672003 A4 0 00300 14 45 0 04800 Lo 00 003000 T8715 0301000 142 Y When preparing rainfall time series files 1t is only necessary to enter periods with non zero rainfall amounts SWMM interprets the rainfall value as a constant value lasting over the recording interval specified for the rain gage which utilizes the time series For all other types of time series SWMM uses interpolation to estimate values at times that fall in between the recorded values 11 7 Interface Files SWMM can use several different kinds of interface files that contain either externally imposed inputs e g rainfall or infiltration inflow hydrographs or the results of previously run analyses e g runoff or routing results These files can help speed up simulations simplify comparisons of different loading scenarios and allow large study areas to be broken up into smaller areas that can be analyzed individually The different types of interface files that are currently available include rainfall interface file runoff interface file hot start file RDI interface file routing interface files Consult Section 8 1 Setting Simulation Options for instructions on how to specify interface files for use as input and or output in a simulation Rainfall and Runo
136. e the coordinates of all objects currently on the map so that their positions relative to one another remain unchanged Selecting this option may then require that the backdrop be re aligned so that its position relative to the drainage area objects is correct Y Exercise caution when selecting the Scale Map to Backdrop Image option in either the Backdrop Image Selector dialog or the Backdrop Dimensions dialog as 1t will modify the coordinates of all existing objects currently on the Study Area Map You might want to save your project before carrying out this step in case the results are not what you expected The name of the backdrop image file and 1ts map dimensions are saved along with the rest of a project s data whenever the project is saved to file For best results in using a backdrop image Use a metafile not a bitmap If the image is loaded before any objects are added to the project then scale the map to it 7 4 Measuring Distances To measure a distance or area on the Study Area Map 1 Click 4 on the Map Toolbar 2 Left click on the map where you wish to begin measuring from 3 Move the mouse over the distance being measured left clicking at each intermediate location where the measured path changes direction 4 Right click the mouse or press lt Enter gt to complete the measurement 5 The distance measured in project units feet or meters will be displayed in a dialog box If the last point on the measured path
137. e typically used to control releases from storage facilities prevent unacceptable surcharging divert flow to treatment facilities and interceptors SWMM can model the following types of flow regulators Orifices Weirs and Outlets Orifices Orifices are used to model outlet and diversion structures in drainage systems which are typically openings in the wall of a manhole storage facility or control gate They are internally represented in SWMM as a link connecting two nodes An orifice can have either a circular or rectangular shape be located either at the bottom or along the side of the upstream node and have a flap gate to prevent backflow Orifices can be used as storage unit outlets under all types of flow routing If not attached to a storage unit node they can only be used in drainage networks that are analyzed with Dynamic Wave flow routing The flow through a fully submerged orifice is computed as O CAJ2gh where Q flow rate C discharge coefficient A area of orifice opening g acceleration of gravity and h head difference across the orifice The height of an orifice s opening can be controlled dynamically through user defined Control Rules This feature can be used to model gate openings and closings The principal input parameters for an orifice include names of its inlet and outlet nodes configuration bottom or side shape circular or rectangular height or elevation above the inlet nod
138. e when the run was stopped will be available for viewing To minimize the SWMM program while a simulation is running click the Minimize button on the Run Status window If the analysis runs successfully the rl icon will appear in the Run Status section of the Status Bar at the bottom of SWMM s main window Any error or warning messages will appear in a Status Report window If you modify the project after a successful run has been made the faucet icon changes to a broken faucet indicating that the current computed results no longer apply to the modified project 8 3 Troubleshooting Results When a run ends prematurely the Run Status dialog will indicate the run was unsuccessful and direct the user to the Status Report for details The Status Report will include an error statement code and description of the problem e g ERROR 138 Node TG040 has initial depth greater than maximum depth Consult Appendix E for a description of SWMM s error messages Even if a run completes successfully one should check to insure that the results are reasonable The following are the most common reasons for a run to end prematurely or to contain questionable results Unknown ID Error Message This message typically appears when an object references another object that was never defined An example would be a subcatchment whose outlet was designated as N29 but no such subcatchment or node with that name exists Similar situations can exist for incorrect r
139. eb EP United States EPA 600 R 05 040 LY Environmental Protection Agency Revised March 2008 STORM WATER MANAGEMENT MODEL USER S MANUAL Version 5 0 By Lewis A Rossman Water Supply and Water Resources Division National Risk Management Research Laboratory Cincinnati OH 45268 NATIONAL RISK MANAGEMENT RESEARCH LABORATORY OFFICE OF RESEARCH AND DEVELOPMENT U S ENVIRONMENTAL PROTECTION AGENCY CINCINNATI OH 45268 DISCLAIMER The information in this document has been funded wholly or in part by the U S Environmental Protection Agency EPA It has been subjected to the Agency s peer and administrative review and has been approved for publication as an EPA document Mention of trade names or commercial products does not constitute endorsement or recommendation for use Although a reasonable effort has been made to assure that the results obtained are correct the computer programs described in this manual are experimental Therefore the author and the U S Environmental Protection Agency are not responsible and assume no liability whatsoever for any results or any use made of the results obtained from these programs nor for any damages or litigation that result from the use of these programs for any purpose FOREWORD The U S Environmental Protection Agency is charged by Congress with protecting the Nation s land air and water resources Under a mandate of national environmental laws the Agency strives to formulate and imp
140. ects color to use for legend background Symbol Width Selects width to use in pixels to draw the symbol portion of the legend Framed Places a frame around the legend Visible Makes the legend visible Graph Options Series The Series page of the Graph Options dialog box controls how individual data series or curves are displayed on a graph To use this page a 2 3 Select a data series to work with from the Series combo box Edit the title used to identify this series in the legend Click the Font button to change the font used for the legend Other legend properties are selected on the Legend page of the dialog Select a property of the data series you would like to modify not all properties are available for some types of graphs The choices are Lines Markers Patterns Labels 126 Profile Plot Options Dialog The Profile Plot Options dialog is used to customize the appearance of a Profile Plot The dialog contains three pages Colors selects the color to use for the plot window panel the plot background a conduit s interior and the depth of filled water includes a Display Conduits Only check box that provides a closer look at the water levels within conduits by removing all other details from the plot Axes edits the main and axis titles including their fonts selects to display horizontal and vertical axis grid lines Node Labels selects to display node ID labels e
141. ed so it can be washed off during our single rainfall event We can either specify the number of antecedent dry days prior to the simulation or directly specify the initial buildup mass on each subcatchment We will use the former method 1 From the Options category of the Data Browser select the Dates sub category and click the button 2 Inthe Simulation Options dialog that appears enter 5 into the Antecedent Dry Days field 3 Leave the other simulation options the same as they were for the dynamic wave flow routing we just completed 4 Click the OK button to close the dialog Now run the simulation by selecting Project gt gt Run Simulation or by clicking on the Standard Toolbar When the run is completed view its Status Report Note that two new sections have been added for Runoff Quality Continuity and Quality Routing Continuity From the Runoff Quality Continuity table we see that there was an initial buildup of 47 5 lbs of TSS on the study area and an additional 2 5 lbs of buildup added during the dry periods of the simulation Almost 48 lbs were washed off during the rainfall event The quantity of Lead washed off is a fixed percentage 25 times 0 001 to convert from mg to ug of the TSS as was specified If you plot the runoff concentration of TSS for subcatchment S and S3 together on the same time series graph as in Figure 2 21 you will see the difference in concentrations resulting from the different mix of land uses
142. eferences made to Curves Time Series Time Patterns Aquifers Snow Packs Transects Pollutants and Land Uses File Errors File errors can occur when a file cannot be located on the user s computer 111 a file being used has the wrong format a file being written cannot be opened because the user does not have write privileges for the directory folder where the file is to be stored SWMM needs to have write privileges for a directory folder where temporary files are stored during a run The original default is the directory where Windows writes its temporary files If this directory does not exist or the user does not have write privileges to it then a new directory must be assigned by using the Program Preferences dialog which is discussed in Section 4 9 Drainage System Layout Errors A valid drainage system layout must obey the following conditions An outfall node can have only one conduit link connected to it A flow divider node must have exactly two outflow links Under Kinematic Wave routing a junction node can only have one outflow link and a regulator link cannot be the outflow link of a non storage node Under Dynamic Wave routing there must be at least one outfall node in the network An error message will be generated if any of these conditions are violated Excessive Continuity Errors When a run completes successfully the mass continuity errors for runoff flow routing and pollutant routin
143. eft corner of the label should appear Enter the text for the label aA w N Ka Press lt Enter gt to accept the label or lt Esc gt to cancel Adding a Non visual Object To add an object belonging to a class that is not displayable on the Study Area Map which includes Climatology Aquifers Snow Packs Unit Hydrographs Transects Control Rules Pollutants Land Uses Curves Time Series and Time Patterns 1 Select the object s category from the list in the Data Browser 2 Click the Y button 3 Edit the object s properties in the special editor dialog form that appears see Appendix C for descriptions of these editors 6 3 Selecting and Moving Objects To select an object on the map 1 Make sure that the map is in Selection mode the mouse cursor has the shape of an arrow pointing up to the left To switch to this mode either click the Select Object button on the Map Toolbar or choose Edit gt gt Select Object from the Main Menu 83 2 Click the mouse over the desired object on the map To select an object using the Data Browser 1 Select the object s category from the upper list in the Browser 2 Select the object from the lower list in the Browser Rain gages subcatchments and nodes can be moved to another location on the Study Area Map To move an object to another location 1 Select the object on the map 2 With the left mouse button held down over the object drag it to its new location 3
144. eing pressurized and could therefore convey more flow than was computed using Kinematic Wave routing We would now like to see what would happen if we apply Dynamic Wave routing instead 23 To run the analysis with Dynamic Wave routing 1 From the Data Browser select the Options category and click the button 2 On the General page of the Simulation Options dialog that appears select Dynamic Wave as the flow routing method 3 On the Dynamic Wave page of the dialog use the settings shown in Figure 2 16 Simulation Options General Dates Time Steps Dynamic Wave Files Inertial Terme O Keep Dampen Ignore Define Supercritical Flow By Slope Froude No Both Force Main Equation Hazen Williams Darcy Weisbach Variable Time Step B Use Adjustment Factor LS 2 tel Conduit Lengthening Minimun Surface Area Use O for No Lengthening Use O for Default Bresa Time Step sec square Feet Figure 2 16 Dynamic Wave simulation options 4 Click OK to close the form and select Project gt gt Run Simulation or click the button to re run the analysis 10 Normally when running a Dynamic Wave analysis one would also want to reduce the routing time step on the Time Steps page of the dialog In this example we will continue to use a 1 minute time step 24 If you look at the Status Report for this run you will see that there is no longer any junction f
145. ength Washoff mass units are the same as used to express the pollutant s concentration milligrams micrograms or counts Rating Curve Washoff The rate of washoff W in mass per second is proportional to the runoff rate raised to some power W C 0 where C washoff coefficient Cz washoff exponent and O runoff rate in user defined flow units Event Mean Concentration This is a special case of Rating Curve Washoff where the exponent is 1 0 and the coefficient C represents the washoff pollutant concentration in mass per liter Note the conversion between user defined flow units used for runoff and liters is handled internally by SWMM Note that in each case buildup is continuously depleted as washoff proceeds and washoff ceases when there is no more buildup available Washoff loads for a given pollutant and land use category can be reduced by a fixed percentage by specifying a BMP Removal Efficiency that reflects the effectiveness of any BMP controls associated with the land use It is also possible to use the Event Mean Concentration option by itself without having to model any pollutant buildup at all Street Sweeping Street sweeping can be used on each land use category to periodically reduce the accumulated buildup of specific pollutants The parameters that describe street sweeping include days between sweeping days since the last sweeping at the start of the simulation the fraction of buildup of all polluta
146. ent Outlets Outlets are flow control devices that are typically used to control outflows from storage units They are used to model special head discharge relationships that cannot be characterized by pumps orifices or weirs Outlets are internally represented in SWMM as a link connecting two nodes An outlet can also have a flap gate that restricts flow to only one direction Outlets attached to storage units are active under all types of flow routing If not attached to a storage unit they can only be used in drainage networks analyzed with Dynamic Wave flow routing A user defined rating curve determines an outlet s discharge flow as a function of the head difference across it Control Rules can be used to dynamically adjust this flow when certain conditions exist 42 The principal input parameters for an outlet include names of its inlet and outlet nodes height or elevation above the inlet node invert function or table containing its head discharge relationship 3 2 10 Map Labels Map Labels are optional text labels added to SWMM s Study Area Map to help identify particular objects or regions of the map The labels can be drawn in any Windows font freely edited and be dragged to any position on the map 3 3 Non Visual Objects In addition to physical objects that can be displayed visually on a map SWMM utilizes several classes of non visual data objects to describe additional characteristics and processes within a s
147. ent Practice that might have been implemented The washoff load computed at each time step is simply reduced by this amount As with the Buildup page each pollutant must be selected in turn from the Pollutant dropdown list and have its pertinent washoff properties defined C 11 Land Use Assignment Editor The Land Use Assignment editor is invoked from the Property Editor when editing the Land Uses property of a subcatchment Its purpose is to assign land uses to the subcatchment for water quality simulations The percent of land area in the subcatchment covered by each land use is entered next to its respective land use category If the land use is not present its field can be left blank The percentages entered do not necessarily have to add up to 100 Land Use Assignment Land Use Z of Area Residential 50 00 Undeveloped BD UU 196 C 12 Pollutant Editor The Pollutant Editor is invoked when a new pollutant object is created or an existing pollutant is selected for editing It contains the following fields Pollutant Editor E N arme Lead Units UGL Hain Concern 0 0 Liv Concer 0 0 l Conce 0 0 Decay Coett 0 0 Snow Only NO Lo Pollutarnt Co Fraction User assigned name of the pollutant Name The name assigned to the pollutant Units The concentration units mg L ug L or L counts L in which the pollutant concentration is expressed Rain Concentration Concentration of the pollutant in r
148. er set Cmin minimum melt coefficient in hr deg F or mm hr deg C Cmax maximum melt coefficient in hr deg F or mm hr deg C Tbase snow melt base temperature deg F or deg C FWE ratio of free water holding capacity to snow depth fraction SDO initial snow depth in or mm water equivalent FWO initial free water in pack in or mm SNNO fraction of impervious area that can be plowed SDTOD snow depth above which there is 100 cover in or mm water equivalent SDplow depth of snow on plowable areas at which redistribution through plowing occurs in or mm FOUL fraction of excess snow on plowable area transferred out of watershed Fimp fraction of excess snow on plowable area transferred to impervious area by plowing Fperv fraction of excess snow on plowable area transferred to pervious area by plowing Fimelt fraction of excess snow on plowable area converted into immediate melt Fsub fraction of excess snow on plowable area transferred to pervious area in another subcatchment Scatch name of subcatchment receiving the Fsubcatch fraction of transferred snow Use one set of PLOWABLE IMPERVIOUS and PERVIOUS lines for each snow pack parameter set created Snow pack parameter sets are associated with specific subcatchments in the SUBCATCHMENTS section Multiple subcatchments can share the same set of snow pack parameters The PLOWABLE line contains parameters for the impervious area of a subcatchment that is subject to
149. erty for an object we must select the object into the Property Editor see Figure 2 5 There are several different ways to do this If the Editor is already visible 12 then you can simply click on the object or select it from the Data page of the Browser Panel of the main window If the Editor is not visible then you can make it appear by one of the following actions double click the object on the map or right click on the object and select Properties from the pop up menu that appears or select the object from the Data page of the Browser panel and then click the Browser s Z button Subcatchment 51 Property Value Mame al Coordinate 5989 99 Y Coordnate 3133 27 Description Tag Ralngage Outlet Area Width Mame of node or another sUubcatchment that recelwez runoff Figure 2 5 Property Editor window Whenever the Property Editor has the focus you can press the F1 key to obtain a more detailed description of the properties listed Two key properties of our subcatchments that need to be set are the rain gage that supplies rainfall data to the subcatchment and the node of the drainage system that receives runoff from the subcatchment Since all of our subcatchments utilize the same rain gage Gage we can use a shortcut method to set this property for all subcatchments at once 1 From the main menu select Edit gt gt Select All 2 Then select Edit gt gt Group Edit to make a Group Editor dialog a
150. es Me Ce a H Map Display Options Data Map Bele Configure Tools mn Tithe Noles A SWMM d Converter Option Climatology Spreadsheet Editor Hydrology W Hydraulics E Quality Figure 12 1 SWMM s Tools menu 147 12 2 Configuring Add in Tools To configure one s personal collection of add in tools select Configure Tools from the Tools menu This will bring up the Tool Options dialog as shown in Figure 12 2 The dialog lists the currently available tools and has command buttons for adding a new tool and for deleting or editing an existing tool The up and down arrow buttons are used to change the order in which the registered tools are listed on the Tools menu Tool Options SWM 4 Converter Spreadsheet Editor Delete Edit Figure 12 2 The Tools Options dialog Whenever the Add or Edit button is clicked on this dialog a Tool Properties dialog will appear as shown in Figure 12 3 This dialog is used to describe the properties of the new tool being added or the existing tool being edited 148 Tool Properties Tool Name Spreadsheet Editor Program C Prograrn Files Microsott Offices Office UNEXCEL EX wowing fa Directory Parameters SINPFILE Macros PAUJDIA Project directory TSM ADI Sy MM directory INPFILE SWM M input file FAPT FILE Sy MA report file FOUTFILE Sy MA output file RIFFILE SWMM runoff interace file Disable SMM while executin
151. es that provide storage volume Physically they could represent storage facilities as small as a catch basin or as large as a lake The volumetric properties of a storage unit are described by a function or table of surface area versus height The principal input parameters for storage units include invert elevation maximum depth depth surface area data evaporation potential ponded surface area when flooded optional external inflow data optional 3 2 7 Conduits Conduits are pipes or channels that move water from one node to another in the conveyance system Their cross sectional shapes can be selected from a variety of standard open and closed geometries as listed in Table 3 1 Most open channels can be represented with a rectangular trapezoidal or user defined irregular cross section shape For the latter a Transect object is used to define how depth varies with distance across the cross section see Section 3 3 5 below The most common shapes for new drainage and sewer pipes are circular elliptical and arch pipes They come in standard sizes that are published by the American Iron and Steel Institute in Modern Sewer Design and by the American Concrete Pipe Association in the Concrete Pipe Design Manual The Filled Circular shape allows the bottom of a circular pipe to be filled with sediment and thus limit its flow capacity The Custom Closed Shape allows any closed geometrical shape that is symmetrical about the cente
152. ex of the subcatchment polygon ordered in a consistent clockwise or counter clockwise sequence Section SYMBOLS Purpose Assigns X Y coordinates to rain gage symbols Format Gage Xcoord Ycoord Remarks Gage name of rain gage Xcoord horizontal coordinate relative to origin in lower left of map Ycoord vertical coordinate relative to origin in lower left of map 252 Section LABELS Purpose Assigns X Y coordinates to user defined map labels Format Xcoord Ycoord Label Anchor Font Size Bold Italic Remarks Xcoord horizontal coordinate relative to origin in lower left of map Ycoord vertical coordinate relative to origin in lower left of map Label text of label surrounded by double quotes Anchor name of node or subcatchment that anchors the label on zoom ins use an empty pair of double quotes if there is no anchor Fonte name of label s font surround by double quotes 1f the font name includes spaces Size font size in points Bold YES for bold font NO otherwise Italic YES for italic font NO otherwise Use of the anchor node feature will prevent the label from moving outside the viewing area when the map is zoomed in on If no font information is provided then a default font is used to draw the label Section BACKDROP Purpose Specifies file name and coordinates of map s backdrop image Formats FILE Fname DIMENSIONS X1 Y1 X2 Y2 Remarks Fname name of file containing backdrop image Ee lower left X coordina
153. f the Simulation Options dialog establishes the length of the time steps used for runoff computation routing computation and results reporting Time steps are specified in days and hours minutes seconds except for flow routing which is entered as decimal seconds Reporting Time Step Enter the time interval for reporting of computed results 107 Runoff Wet Weather Time Step Enter the time step length used to compute runoff from subcatchments during periods of rainfall or when ponded water still remains on the surface Runoff Dry Weather Time Step Enter the time step length used for runoff computations consisting essentially of pollutant buildup during periods when there is no rainfall and no ponded water This must be greater or equal to the Wet Weather time step Routing Time Step Enter the time step length in decimal seconds used for routing flows and water quality constituents through the conveyance system Note that Dynamic Wave routing requires a much smaller time step than the other methods of flow routing Dynamic Wave Options The Dynamic Wave page of the Simulation Options dialog sets several parameters that control how the dynamic wave flow routing computations are made These parameters have no effect for the other flow routing methods Inertial Terms Indicates how the inertial terms in the St Venant momentum equation will be handled KEEP maintains these terms at their full value under all conditions D
154. ff Files The rainfall and runoff interface files are binary files created internally by SWMM that can be saved and reused from one analysis to the next The rainfall interface file collates a series of separate rain gage files into a single rainfall data file Normally a temporary file of this type is created for every SWMM analysis that uses external rainfall data files and is then deleted after the analysis is completed However if the same rainfall data are being used with many different analyses requesting SWMM to save the rainfall interface file after the first run and then reusing this file in subsequent runs can save computation time Y The rainfall interface file should not be confused with a rainfall data file The latter is an external text file that provides rainfall time series data for a single rain gage The former is a binary file created internally by SWMM that processes all of the rainfall data files used by a project The runoff interface file can be used to save the runoff results generated from a simulation run If runoff is not affected in future runs the user can request that SWMM use this interface file to supply runoff results without having to repeat the runoff calculations again 143 Hot Start Files Hot start files are binary files created by SWMM that contain hydraulic and water quality variables for the drainage system at the end of a run These data consist of the water depth and concentration of each pollutan
155. g Update SMM after closing Figure 12 3 The Tool Properties dialog The data entry fields of the Tool Properties dialog consist of the following Tool Name This is the name to be used for the tool when it is displayed in the Tools Menu Program Enter the full path name to the program that will be launched when the tool is selected You can click the 4 button to bring up a standard Windows file selection dialog from which you can search for the tool s executable file name Working Directory This field contains the name of the directory that will be used as the working directory when the Lah tool is launched You can click the button to bring up a standard directory selection dialog from which you can search for the desired directory You can also enter the macro symbol SPROJDIR to utilize the current SWMM project s directory or SWMMDIR to use the directory where the SWMM 5 executable resides Either of these macros can also be inserted into the Working Directory field by selecting its name in the list of macros provided on the dialog and then clicking the button This field can be left blank in which case the system s current directory will be used 149 Parameters This field contains the list of command line arguments that the tool s executable program expects to see when it is launched Multiple parameters can be entered as long as they are separated by spaces A number of special macro symbols have bee
156. g a control curve a time series or a PID controller To model these types of controls the value entry on the right hand side of the action clause is replaced by the keyword CURVE TIMESERIES or PID and followed by the id name of the respective control curve or time series or by the gain integral time in minutes and derivative time in minutes of a PID controller For direct action control the gain is a positive number while for reverse action control it must be a negative number By convention the controller variable used in a control curve or PID control will always be the object and attribute named in the last condition clause of the rule The value specified for this clause will be the setpoint used in a PID controller 236 Examples Some examples of action clauses are PUMP P67 STATUS OFF ORIFICE Q212 SETTING Das WEIR WZ gt SETTING CURVE C25 ORTFICE ORI 29 SETTING PID Ow 01 020 Only the RULE IF and THEN portions of a rule are required the other portions are optional When mixing AND and OR clauses the OR operator has higher precedence than AND 1 e IF Acor B and C is equivalent to LE A Or B8 and C If the interpretation was meant to be IEA Or B and C then this can be expressed using two rules as in IF A THEN Le Band C THEN The PRIORITY value is used to determine which rule applies when two or more rules require that conflicting actions be taken on a link A rule without a priority value alwa
157. g to x Multiple pairs of x y values can appear on a line If more than one line is needed repeat the curve s name but not the type on subsequent lines The x values must be entered in increasing order Choices for curve type have the following meanings flows are expressed in the user s choice of flow units set in the OPTIONS section STORAGE surface area in ft m v depth in ft m for a storage unit node SHAPE width v depth for a custom closed cross section both normalized with respect to full depth DIVERSION diverted outflow v total inflow for a flow divider node TIDAL water surface elevation in ft m v hour of the day for an outfall node PUMP 1 pump outflow v increment of inlet node volume in ft m PUMP 2 pump outflow v increment of inlet node depth in ft m PUMP 3 pump outflow v head difference between outlet and inlet nodes in ft m PUMP 4 pump outflow v continuous depth in ft m RATING outlet flow v head in ft m CONTROL control setting v controller variable See Section 3 2 for illustrations of the different types of pump curves Storage curve x depth y surface area ACI STORAGE 0 1000 2 2000 4 3500 6 4200 8 5000 Typel pump curve x inlet wet well volume y flow POL PUMPI PCI 200 300s 10 300 20 247 Section Purpose Formats Remarks Examples TIMESERIES Describes how a quantity varies over time Name Date Hour Value Na
158. g will be displayed in the Run Status window These errors represent the percent difference between initial storage total inflow and final storage total outflow for the entire drainage system If they exceed some reasonable level such as 10 percent then the validity of the analysis results must be questioned The most common reasons for an excessive continuity error are computational time steps that are too long or conduits that are too short Run Status a A UL Aun Was successful Continuity Error Surface Furiott Flow R outing Quality Routing In addition to the system continuity error the Status Report produced by a run see Section 9 1 will list those nodes of the drainage network that have the largest flow continuity errors If the error for a node is excessive then one should first consider if the node in question is of importance to the purpose of the simulation If it is then further study is warranted to determine how the error might be reduced 112 Unstable Flow Routing Results Due to the explicit nature of the numerical methods used for Dynamic Wave routing and to a lesser extent Kinematic Wave routing the flows in some links or water depths at some nodes may fluctuate or oscillate significantly at certain periods of time as a result of numerical instabilities in the solution method SWMM does not automatically identify when such conditions exist so it is up to the user to verify the numerical stabili
159. ge of the Climatology Editor Dialog is used to specify points on the Areal Depletion Curves for both impervious and pervious surfaces within a project s study area These curves define the relation between the area that remains snow covered and snow pack depth Each curve is defined by 10 equal increments of relative depth ratio between 0 and 0 9 Relative depth ratio is the ratio of an area s current snow depth to the depth at which there is 100 areal coverage Enter values in the data grid provided for the fraction of each area that remains snow covered at each specified relative depth ratio Valid numbers must be between O and 1 and be increasing with increasing depth ratio Clicking the Natural Area button fills the grid with values that are typical of natural areas Clicking the No Depletion button will fill the grid with all 1 s indicating that no areal depletion occurs This is the default for new projects 176 Climatology Editor Evaporation Wind Speed Snow Melt Areal Depletion Fraction of rea Covered by Snow No Depletion No Depletion Natural Srea Natural rea C 3 Control Rules Editor Control Rules Editor POLE PUMPLA IF MODE S501 DEPTH 4 THEN PUMP PUMP1 status PRIORITY 1 POLE POMPI1E IF MODE S01 DEPTH 1 THEN PUMP PUMP status PRIORITY 1 Click Help to review format of Control Rule statements 177 The Control Rules Editor is invoked whenever a new control rule is created or an existing r
160. h by holding down the lt Shift gt key while drawing a zoom rectangle with the mouse s left button held down Drawing the rectangle from left to right zooms in drawing it from right to left zooms out The plot can also be panned in any direction by holding down the lt Ctrl gt key and moving the mouse across the plot with the left button held down An opened graph will normally be redrawn when a new simulation is run To prevent the automatic updating of a graph once a new set of results is computed you can lock the current graph by clicking the Ed icon in the upper left corner of the graph To unlock the graph click the icon again Time Series Plots A Time Series Plot graphs the value of a particular variable at up to six locations against time When only a single location is plotted and that location has calibration data registered for the plotted variable then the calibration data will be plotted along with the simulated results see Section 5 5 for instructions on how to register calibration data with a project To create a Time Series Plot 1 Select Report gt gt Graph gt gt Time Series from the Main Menu or click E on the Standard Toolbar 2 A Time Series Plot dialog will appear Use it to describe what objects and quantities should be plotted 120 Time Series Plot Start Date End Date 062722002 w 06 27 2002 kd Time Format Object Categor Elapsed Time Na Links V ariabiez Links Y Depth Velocity Froude
161. h category of defaults will be discussed next Default ID Labels The ID Labels page of the Project Defaults dialog form is used to determine how SWMM will assign default ID labels for the visual project components when they are first created For each type of object you can enter a label prefix in the corresponding entry field or leave the field blank if an object s default name will simply be a number In the last field you can enter an increment to be used when adding a numerical suffix to the default label As an example if C were used as a prefix for Conduits along with an increment of 5 then as conduits are created they receive default names of C5 C10 C15 and so on An object s default name can be changed by using the Property Editor for visual objects or the object specific editor for non visual objects 74 Project Defaults ID Labels Subcatchments Nodes Links Object ID Pret Rain Gages Subcatchments Junctions Outtalls Storage Units Conduits Pump Regulators ID Increment Save as defaults for all new projects Default Subcatchment Properties The Subcatchment page of the Project Defaults dialog sets default property values for newly created subcatchments These properties include Subcatchment Area Characteristic Width Slope Impervious Impervious Area Roughness Pervious Area Roughness Impervious Area Depression Storage Pervious Area Depression Storage of Impervious
162. hannel h i f g A L P Y f 799 Li ci 20 40 60 50 400 1420 140 Station Figure 3 4 Example of a natural channel transect Each transect must be given a unique name Conduits refer to that name to represent their shape A special Transect Editor is available for editing the station elevation data of a transect SWMM internally converts these data into tables of area top width and hydraulic radius versus channel depth In addition as shown in the diagram above each transect can have a left and right overbank section whose Manning s roughness can be different from that of the main channel This feature can provide more realistic estimates of channel conveyance under high flow conditions 3 3 6 External Inflows In addition to inflows originating from subcatchment runoff and groundwater drainage system nodes can receive three other types of external inflows Direct Inflows These are user defined time series of inflows added directly into a node They can be used to perform flow and water quality routing in the absence of any runoff computations as in a study area where no subcatchments are defined Dry Weather Inflows These are continuous inflows that typically reflect the contribution from sanitary sewage in sewer systems or base flows in pipes and stream channels They are represented by an average inflow rate that can be periodically adjusted on a monthly daily and hourly basis by applying Time Pattern multiplie
163. he area of a 4 ft diameter manhole is used TEMPDIR provides the name of a file directory or folder where SWMM writes its temporary files If the directory name contains spaces then it should be placed within double quotes If no directory is specified then the temporary files are written to the current directory that the user is working in Section Purpose Formats Remarks REPORT Describes the contents of the report file that is produced INPUT YES NO CONTINUITY YES NO FLOWSTATS YES NO CONTROLS YES NO SUBCATCHMENTS ALL NONE lt list of subcatchment names gt NODES ALL NONE lt list of node names gt LINKS ALL NONE lt list of link names gt INPUT specifies whether or not a summary of the input data should be provided in the output report The default is NO CONTINUITY specifies whether continuity checks should be reported or not The default is YES FLOWSTATS specifies whether summary flow statistics should be reported or not The default is YES CONTROLS specifies whether all control actions taken during a simulation should be listed or not The default is NO SUBCATCHMENTS gives a list of subcatchments whose results are to be reported The default is NONE NODES gives a list of nodes whose results are to be reported The default is NONE LINKS gives a list of links whose results are to be reported The default is NONE The SUBCATCHMENTS NODES and LINKS lines can be repeated mul
164. he control variable setpoint x and its value at time t x t normalized to the setpoint value e t x x t x Note that for direct action control where an increase in the link setting causes an increase in the controlled variable the sign of Kp must be positive For reverse action control where the controlled variable decreases as the link setting increases the sign of Kp must be negative The user must recognize whether the control 1s direct or reverse action and use the proper sign on Kd accordingly For example adjusting an orifice opening to maintain a desired downstream flow is direct action Adjusting it to maintain a downstream water level is reverse action while adjusting it to maintain an upstream water level is direct action Controlling a pump to maintain a fixed wet well water level would be reverse action while using it to maintain a fixed downstream flow is direct action C 4 Cross Section Editor The Cross Section Editor dialog is used to specify the shape and dimensions of a conduit s cross section When a shape is selected from the dropdown combo box an appropriate set of edit fields appears for describing the dimensions of that shape Length dimensions are in units of feet for US units and meters for SI units Slope values represent ratios of horizontal to vertical distance The Barrels field specifies how many identical parallel conduits exist between its end nodes If an Irregular shaped section is chosen a drop do
165. he grid as well as options to insert or delete a row Clicking the View button will bring up a window that illustrates the shape of the transect cross section C 18 Treatment Editor The Treatment Editor is invoked whenever the Treatment property of a node is selected from the Property Editor It displays a list of the project s pollutants with an edit box next to each as shown below Enter a valid treatment expression in the box next to each pollutant which receives treatment Refer to the Treatment topic in Section 3 3 to learn what constitutes a valid treatment expression Treatment Editor for Node 16 Treatment expressions have the general form R fP BP Vi Or fIP BP Y Where D fractional removal outlet concentration C D one or more pollutant names E D one or more pollutant removals prepend PB to pollutant name T one or more process variables 205 C 19 Unit Hydrograph Editor The Unit Hydrograph Editor is invoked whenever a new unit hydrograph object is created or an existing one is selected for editing It is used to specify the shape parameters and rain gage for a group of triangular unit hydrographs These hydrographs are used to compute rainfall derived infiltration inflow R DID flow at selected nodes of the drainage system A UH group can contain up to 12 sets of unit hydrographs one for each month of the year and each set can consist of up to 3 individual hydrographs for short term intermediate
166. he upstream end dry on the downstream end subcritical flow supercritical flow critical flow at the upstream end critical flow at the downstream end Average Froude number Average change in flow between each time step flow units Conduit Surcharging Hours that conduit is full at both ends upstream end downstream end Hours that conduit flows above full normal flow Hours that conduit is capacity limited Note only conduits with one or more non zero entries are listed and a conduit is considered capacity limited if its upstream end is full and the HGL slope is greater than the conduit slope Pumping Summary Percent of time that the pump is on line Maximum flow pumped flow units Average flow pumped flow units Total energy consumed assuming 100 efficiency kwatt hours Percent of time that the pump operates off of its pump curve The Status Report can be viewed by selecting Report gt gt Status from the Main Menu Its window includes a Bookmarks panel that makes it easy to navigate between the topics listed above To copy selected text from the Status Report to a file or to the Windows Clipboard first select the text to copy with the mouse and then choose Edit gt gt Copy To from the Main Menu or press the ES button on the Standard T oolbar If the entire report is to be copied then it is not necessary to first select text with the mouse To locate an object that is listed in one of the Status Report s tables fi
167. hoices are C function computes effluent concentration R function computes fractional removal Func mathematical function expressing treatment result in terms of pollutant concentrations pollutant removals and other standard variables see below Treatment functions can be any well formed mathematical expression involving inlet pollutant concentrations use the pollutant name to represent a concentration removal of other pollutants use R_ prepended to the pollutant name to represent removal process variables which include FLOW for flow rate into node user s flow units DEPTH for water depth above node invert ft or m AREA for node surface area ft2 or m2 DT for routing time step seconds HRT for hydraulic residence time hours Examples 1 st order decay of BOD Node23 BOD C BOD exp 0 05 HRT lead removal is 20 of TSS removal Node23 Lead R 0 2 R_TSS 242 Section DWE Purpose Specifies dry weather flow and its quality entering the drainage system at specific nodes Format Node Item Value Pati Pat2 Pat3 Pat Remarks Node name of node where dry weather flow enters Item keyword FLOW for flow or pollutant name for quality constituent Value average baseline value for corresponding Item flow or concentration units Patl Pat2 etc names of up to four time patterns appearing in the PATTERNS section The actual dry weather input will equal the product of the baseline valu
168. id overbank locations The distance values specified for either the left or right overbank locations of a transect do not match any of the distances listed for the transect s stations Transect xxx has no depth All of the stations for a transect were assigned the same elevation invalid treatment function expression at line n of input file 258 ERROR 301 ERROR 303 ERROR 305 ERROR 307 ERROR 309 ERROR 311 ERROR 313 ERROR 315 ERROR 317 ERROR 319 ERROR 321 A treatment function supplied for a pollutant at a specific node is either not a correctly formed mathematical expression or refers to unknown pollutants process variables or math functions files share same names The input report and binary output files specified on the command line cannot have the same names cannot open input file The input file either does not exist or cannot be opened e g it might be in use by another program cannot open report file The report file cannot be opened e g it might reside in a directory to which the user does not have write privileges cannot open binary results file The binary output file cannot be opened e g it might reside in a directory to which the user does not have write privileges error writing to binary results file There was an error in trying to write results to the binary output file e g the disk might be full or the file size exceeds the limit imposed by the operat
169. idered to be in steady state if the change in external inflows at each node is below 0 5 cfs and the relative difference between total system inflow and outflow is below 5 Ignore Rainfall Runoff Check this option to ignore all rainfall data and runoff computations Only user specified direct inflow time series and dry weather inflows will be considered Date Options The Dates page of the Simulation Options dialog determines the starting and ending dates times of a simulation Start Analysis On Enter the date month day year and time of day when the simulation begins Start Reporting On Enter the date and time of day when reporting of simulation results is to begin This must be on or after the simulation starting date and time End Analysis On Enter the date and time when the simulation is to end Start Sweeping On Enter the day of the year month day when street sweeping operations begin The default is January 1 End Sweeping On Enter the day of the year month day when street sweeping operations end The default is December 31 Antecedent Dry Days Enter the number of days with no rainfall prior to the start of the simulation This value is used to compute an initial buildup of pollutant load on the surface of subcatchments If rainfall or climate data are read from external files then the simulation dates should be Set to coincide with the dates recorded in these files Time Step Options The Time Steps page o
170. ileges to its directory incompatible data found in runoff interface file SWMM was trying to read data from a designated runoff interface file with the wrong format 1 e it may have been created for some other project or actually be some other type of file attempting to read beyond end of runoff interface file This error can occur when a previously saved runoff interface file 1s being used in a simulation with a longer duration than the one that created the interface file error in reading from runoff interface file A format error was encountered while trying to read data from a previously saved runoff interface file cannot open hotstart interface file xxx A hotstart interface file could not be opened possibly because it does not exist or because the user does not have write privileges to its directory incompatible data found in hotstart interface file SWMM was trying to read data from a designated hotstart interface file with the wrong format 1 e it may have been created for some other project or actually be some other type of file error in reading from hotstart interface file A format error was encountered while trying to read data from a previously saved hotstart interface file no climate file specified for evaporation and or wind speed This error occurs when the user specifies that evaporation or wind speed data will be read from an external climate file but no name is supplied for the file cannot open climat
171. in the same climate file used for daily minimum maximum temperatures Snowmelt Snowmelt parameters are climatic variables that apply across the entire study area when simulating snowfall and snowmelt They include the air temperature at which precipitation falls as snow heat exchange properties of the snow surface study area elevation latitude and longitude correction Areal Depletion Areal depletion refers to the tendency of accumulated snow to melt non uniformly over the surface of a subcatchment As the melting process proceeds the area covered by snow gets reduced This behavior is described by an Areal Depletion Curve that plots the fraction of total area that remains snow covered against the ratio of the actual snow depth to the depth at which there is 100 snow cover A typical ADC for a natural area is shown in Figure 3 2 Two such curves can be supplied to SWMM one for impervious areas and another for pervious areas Hacdon now Co veta d Figure 3 2 Areal Depletion curve for a natural area 3 3 2 Snow Packs Snow Pack objects contain parameters that characterize the buildup removal and melting of snow over three types of sub areas within a subcatchment The Plowable snow pack area consists of a user defined fraction of the total impervious area It 19 meant to represent such areas as streets and parking lots where plowing and snow removal can be done The Impervious snow pack area covers the remaining impe
172. in these two areas You can also see that the duration over which pollutants are washed off is much shorter than the duration of the entire runoff hydrograph i e 1 hour versus about 6 hours This results from having exhausted the available buildup of TSS over this period of time 28 2 7 Graph 5ubcatchment 155 Subcatchment TSS Subcatch 1 Subcatch Ss E a Elapsed Time hours Figure 2 21 TSS concentration of runoff from selected subcatchments Running a Continuous Simulation As a final exercise in this tutorial we will demonstrate how to run a long term continuous simulation using a historical rainfall record and how to perform a statistical frequency analysis on the results The rainfall record will come from a file named sta310301 dat that was included with the example data sets provided with EPA SWMM It contains several years of hourly rainfall beginning in January 1998 The data are stored in the National Climatic Data Center s DSI 3240 format which SWMM can automatically recognize To run a continuous simulation with this rainfall record i 2 ce Select the rain gage Gage into the Property Editor Change the selection of Data Source to FILE Select the File Name data field and click the ellipsis button or press the Enter key to bring up a standard Windows File Selection dialog Navigate to the folder where the SWMM example files were stored select the file named sta310301 dat and click Open to selec
173. ing system error reading from binary results file The command line version of SWMM could not read results saved to the binary output file when writing results to the report file cannot open scratch rainfall interface file SWMM could not open the temporary file it uses to collate data together from external rainfall files cannot open rainfall interface file xxx SWMM could not open the specified rainfall interface file possibly because it does not exist or because the user does not have write privileges to its directory cannot open rainfall data file xxx An external rainfall data file could not be opened most likely because it does not exist invalid format for rainfall interface file SWMM was trying to read data from a designated rainfall interface file with the wrong format 1 e it may have been created for some other project or actually be some other type of file no data in rainfall interface file for gage xxx This message occurs when a project wants to use a previously saved rainfall interface file but cannot find any data for one of its rain gages in the interface file 259 ERROR 323 ERROR 325 ERROR 327 ERROR 329 ERROR 331 ERROR 333 ERROR 335 ERROR 336 ERROR 337 ERROR 338 ERROR 339 ERROR 341 ERROR 343 cannot open runoff interface file xxx A runoff interface file could not be opened possibly because it does not exist or because the user does not have write priv
174. ir condition grass cover on 50 75 of the area 49 69 79 84 Commercial and business areas 85 89 92 94 95 impervious Industrial districts 72 impervious _ districts 72 impervious 81 88 91 93 Residential 2 Average lot size Impervious 1 8 ac or less 65 77 85 90 92 1 4 ac 38 61 75 83 87 1 3 ac 30 57 72 81 86 1 2 ac 25 S K S 7 1 ac 20 Ga parking lots roofs driveways 98 98 98 98 Streets and roads Paved with curbs and storm sewers 98 98 98 98 Gravel 76 85 89 91 Dirt 72 82 87 89 1 Antecedent moisture condition II Source SCS Urban Hydrology for Small Watersheds 2 Ed TR 55 June 1986 2 Good cover is protected from grazing and litter and brush cover soil 3 Curve numbers are computed assuming that the runoff from the house and driveway is directed toward the street with a minimum of roof water directed to lawns where additional infiltration could occur 4 The remaining pervious areas lawn are considered to be in good pasture condition for these curve numbers 5 In some warmer climates of the country a curve number of 95 may be used 156 A 5 A 6 Depression Storage Impervious surfaces 0 05 0 10 inches Lawns 0 10 0 20 inches Pasture 0 20 inches Forest litter 0 30 inches Source ASCE 1992 Design amp Construction of Urban Stormwater Management Systems New York NY Manning s n Overland Flow Surface in Sm
175. ir default settings 4 Click the OK button to close the Editor 5 Click the button on the Data Browser again to add our next pollutant 6 In the Pollutant Editor enter Lead for the pollutant name select ug L for the concentration units enter TSS as the name of the Co Pollutant and enter 0 25 as the Co Fraction value 7 Click the OK button to close the Editor In SWMM pollutants associated with runoff are generated by specific land uses assigned to subcatchments In our example we will define two categories of land uses Residential and Undeveloped To add these land uses to the project H Aside from surface runoff SWMM allows pollutants to be introduced into the nodes of a drainage system through user defined time series of direct inflows dry weather inflows groundwater interflow and rainfall dependent inflow infiltration 25 1 Under the Quality category in the Data Browser select the Land Uses sub category and click the button 2 In the Land Use Editor dialog that appears see Figure 2 18 enter Residential in the Name field and then click the OK button 3 Repeat steps 1 and 2 to create the Undeveloped land use category Pollutant Editor Property Talus OOOO Land Use Editor Mame General Units Buildup Washolt ap eee Property Value Awe Land Use Mame Pesidential Description IS Concern STREET CLEANING Decay Coeff b Interval Snow Only Aval abilit Co Pollutant j Co Fr
176. ist of two zones a lower saturated zone and an upper unsaturated Zone Name Por WP FC K Ks PS UEF LED GWR BE WTE UMC Name POr WP FC LED GWR BE WTE UMC name assigned to aquifer soil porosity volumetric fraction soil wilting point volumetric fraction soil field capacity volumetric fraction saturated hydraulic conductivity in hr or mm hr slope of hydraulic conductivity versus moisture content curve in hr or mm hr slope of soil tension versus moisture content curve inches or mm fraction of total evaporation available for evapotranspiration in the upper unsaturated zone maximum depth into the lower saturated zone over which evapotranspiration can occur ft or m rate of percolation from saturated zone to deep groundwater when water table is at ground surface in hr or mm hr elevation of the bottom of the aquifer ft or m water table elevation at start of simulation ft or m unsaturated zone moisture content at start of simulation volumetric fraction 222 Section Purpose Formats Remarks GROUNDWATER Supplies parameters that determine the rate of groundwater flow between the aquifer underneath a subcatchment and a node of the conveyance system Subcat Aquifer Node SurfEl Al Bl A2 B2 AS TW E Subcat subcatchment name Aquifer name of groundwater aquifer underneath the subcatchment Node name of node in conveyance system exchanging groundwater with aquifer
177. ither along the plot s top axis directly on the plot above the node s crown height or both selects the length of arrow to draw between the node label and the node s crown on the plot use O for no arrows selects the font size of the node ID labels Profile Plot Options Colors Anes Il Node Labels Plot Background _ white Conduit Interior Info Background e Water Depth LJ Aqua Display Conduits Only Check the Default box if you want these options to apply to all new profile plots when they are first created 127 9 6 Viewing Results with a Table Time series results for selected variables and objects can also be viewed in a tabular format There are two types of formats available Table by Object tabulates the time series of several variables for a single object e g flow and water depth for a conduit x Table Link 7 Siz 01 00 00 02 00 00 03 00 00 04 00 00 05 00 00 Table by Variable tabulates the time series of a single variable for several objects of the same type e g runoff for a group of subcatchments Table Subcatch Runoff Subeatch 2 01 00 00 0 00 02 00 00 03 00 00 04 00 00 05 00 00 To create a tabular report 1 Select Report gt gt Table from the Main Menu or click on the Standard Toolbar 2 Choose the table format either By Object or By Variable from the sub menu that appears 3 Fill in the Table by Object or Table by Variable di
178. k the OK button type to begin the setup process The setup program will ask you to choose a folder directory where the SWMM program files will be placed The default folder is c Program Files EPA SWMM 5 0 After the files are installed your Start Menu will have a new item named EPA SWMM 5 0 To launch SWMM simply select this item off of the Start Menu and then select EPA SWMM 5 0 from the submenu that appears The name of the executable file that runs SWMM under Windows is epaswmm23 exe Under Windows 2000 XP and Vista a user s personal settings for running SWMM are stored in a folder named EPASWMM under the user s Application Data directory If you need to save these settings to a different location you can install a shortcut to SWMM 5 on the desktop whose target entry includes the name of the SWMM 5 executable followed by s lt userfolder gt where lt userfolder gt is the name of the folder where the personal settings will be stored An example might be c Program File NEPA SWMM 5 0 epaswmms5 exe s My Folders WM MSN To remove EPA SWMM from your computer do the following 1 Select Settings from the Windows Start menu Select Control Panel from the Settings menu Select EPA SWMM 5 0 from the list of programs that appears 2 3 Double click on the Add Remove Programs item 4 5 Click the Add Remove button 1 5 Steps in Using SWMM One typically carries out the following steps when using SWMM to model sto
179. kes to open a closed or close an open gated orifice Close in decimal hours Use 0 or leave blank if timed openings closings do not apply Use Control Rules to adjust gate position 168 B 10 Weir Properties Name User assigned weir name Inlet Node Name of node on inlet side of weir Outlet Node Name of node on outlet side of weir Description Click the ellipsis button or press Enter to edit an optional description of the weir Tag Optional label used to categorize or classify the weir Type Weir type TRANSVERSE SIDEFLOW V NOTCH or TRAPEZOIDAL Height Vertical height of weir opening feet or meters Length Horizontal length of weir opening feet or meters Side Slope Slope width to height of side walls for a V NOTCH or TRAPEZOIDAL weit Inlet Offset Depth or elevation of bottom of weir opening from invert of inlet node feet or meters see note below table of Conduit Properties Discharge Coeff Discharge coefficient for flow through the central portion of the weir for flow in CFS when using US units or CMS when using SI units Typical values are 3 33 US 1 84 SI for sharp crested transverse weirs 2 5 3 3 US 1 38 1 83 SI for broad crested rectangular weirs 2 4 2 8 US 1 35 1 55 SI for V notch triangular weirs Flap Gate YES if the weir has a flap gate that prevents backflow NO if it does not End Coeff Discharge coefficient for flow through the tria
180. l penetrating the ground surface into the unsaturated soil zone of pervious subcatchments areas SWMM offers three choices for modeling infiltration Horton s Equation This method is based on empirical observations showing that infiltration decreases exponentially from an initial maximum rate to some minimum rate over the course of a long rainfall event Input parameters required by this method include the maximum and minimum infiltration rates a decay coefficient that describes how fast the rate decreases over time and a time it takes a fully saturated soil to completely dry Green Ampt Method This method for modeling infiltration assumes that a sharp wetting front exists in the soil column separating soil with some initial moisture content below from saturated soil above The input parameters required are the initial moisture deficit of the soil the soil s hydraulic conductivity and the suction head at the wetting front Curve Number Method This approach is adopted from the NRCS SCS Curve Number method for estimating runoff It assumes that the total infiltration capacity of a soil can be found from the soil s tabulated Curve Number During a rain event this capacity is depleted as a function of cumulative rainfall and 54 remaining capacity The input parameters for this method are the curve number the soil s hydraulic conductivity used to estimate a minimum separation time for distinct rain events and a time it takes a fully sa
181. lement actions leading to a compatible balance between human activities and the ability of natural systems to support and nurture life To meet this mandate EPA s research program is providing data and technical support for solving environmental problems today and building a science knowledge base necessary to manage our ecological resources wisely understand how pollutants affect our health and prevent or reduce environmental risks in the future The National Risk Management Research Laboratory is the Agency s center for investigation of technological and management approaches for reducing risks from threats to human health and the environment The focus of the Laboratory s research program is on methods for the prevention and control of pollution to the air land water and subsurface resources protection of water quality in public water systems remediation of contaminated sites and ground water and prevention and control of indoor air pollution The goal of this research effort is to catalyze development and implementation of innovative cost effective environmental technologies develop scientific and engineering information needed by EPA to support regulatory and policy decisions and provide technical support and information transfer to ensure effective implementation of environmental regulations and strategies Water quality impairment due to runoff from urban and developing areas continues to be a major threat to the ecological health
182. lier for each day of the week 201 HOURLY One multiplier for each hour from 12 midnight to 11 PM WEEKEND Same as for HOURLY except applied to weekend days Y In order to maintain an average dry weather flow or pollutant concentration at its specified value as entered on the Inflows Editor the multipliers for a pattern should average to 1 0 C 15 Time Series Editor The Time Series Editor is invoked whenever a new time series object is created or an existing time series is selected for editing To use the Time Series Editor Time Series Editor Time Seres Name 02303 Description Direct Inflow at Node 82309 Ho dates means times are relative to start of simulation Date Time MD AY H M Value 1 Enter values for the following data entry fields Name Name of the time series Description Optional comment or description of what the time series represents Click the Z button to launch a multi line comment editor if more than one line is needed Date Column Optional date in month day year format of the time series values only needed at points in time where a new date occurs 202 Time Column If dates are used enter the military time of day for each time series value as hours minutes or decimal hours If dates are not used enter time as hours since the start of the simulation Value Column The time series numerical values 2 Click the View button to see a graphical plot of the time series
183. line links X Y coordinates and text of labels X Y coordinates for rain gages gt X Y coordinates of the bounding rectangle and file name of the backdrop X Y coordinates for each vertex of subcatchment polygons image X Y coordinates of the map COORDINATES X Y coordinates for nodes X Map Data Section POLYGONS VERTICES LABELS SYMBOLS BACKDROP rain gages as bitmap symbols In addition it can display text labels and a backdrop image such as MAP a street map The GUI has tools for drawing editing moving and displaying these map elements The map s coordinate data are stored in the format described below Normally these data are simply appended to the SWMM input file by the GUI so users do not have to concern themselves with it However it 1s sometimes more convenient to import map data from some other source such as a CAD or GIS file rather than drawing a map from scratch using the GUI In this case the link 3 has interior vertices which give it a curved shape Also observe that this map s coordinate system has no units so that the positions of its objects may not necessarily coincide to their real Figure D 2 displays a sample map and Figure D 3 the data that describes it Note that only one world locations SWMM s graphical user interface GUI can display a schematic map of the drainage area being analyzed This map displays subcatchments as polygons nodes as circles links as polylines
184. ll lengths and areas box if you would like SWMM to re calculate all conduit lengths and subcatchment areas under the new set of map dimensions 5 Click the OK button to resize the map Map Dimensions Lower Lett Upper Right coordinate 0 000 coordinate 10000 000 coordinate 0 000 coordinate 10000 000 Map Units C Feet Meters Degrees None Auto Length iz ON Re compute all lengths and areas m Y If you are going to use a backdrop image with the automatic distance and area calculation feature then it is recommended that you set the map dimensions immediately after creating a new project Map distance units can be different from conduit length units The latter feet or meters depend on whether flow rates are expressed in US or metric units SWMM will automatically convert units 1f necessary 7 3 Utilizing a Backdrop Image SWMM can display a backdrop image behind the Study Area Map The backdrop image might be a street map utility map topographic map site development plan or any other relevant picture or drawing For example using a street map would simplify the process of adding sewer lines to the project since one could essentially digitize the drainage system s nodes and links directly on top of it Study rea Map 90 The backdrop image must be a Windows metafile bitmap or JPEG image created outside of SWMM Once imported its features cannot be edited although its sc
185. llut JInitBuildup Pollut InitBuildup Remarks Subcat name of a subcatchment Pollut name of a pollutant InitBuildup initial buildup of pollutant lbs acre or kg hectare More than one pair of pollutant buildup values can be entered per line If more than one line is needed then the subcatchment name must still be entered first on the succeeding lines If an initial buildup is not specified for a pollutant then its initial buildup is computed by applying the DRY_DAYS option specified in the OPTIONS section to the pollutant s buildup function for each land use in the subcatchment Section RDII Purpose Specifies the parameters that describe rainfall derived infiltration inflow entering the drainage system at specific nodes Format Node UHgroup SewerArea Remarks Node name of a node UHgroup name of an RDI unit hydrograph group specified in the HYDROGRAPHS section SewerArea area of the sewershed which contributes RDII to the node acres or hectares 245 Section Purpose Formats Remarks Examples HYDROGRAPHS Specifies the shapes of the triangular unit hydrographs that determine the amount of rainfall derived infiltration inflow R DID entering the drainage system Name Raingage Name Month Ri TI Kl Ra T2 K2 Ro TS K3 Name name assigned to a unit hydrograph UH group Raingage name of rain gage used by UH group Month month of the year e g JAN FEB etc or ALL for all months R1 R2 R3 res
186. looding and that the peak flow carried by conduit C2 has been increased from 3 52 cfs to 4 05 cfs 2 6 Simulating Water Quality In the next phase of this tutorial we will add water quality analysis to our example project SWMM has the ability to analyze the buildup washoff transport and treatment of any number of water quality constituents The steps needed to accomplish this are 1 Identify the pollutants to be analyzed 2 Define the categories of land uses that generate these pollutants 3 Set the parameters of buildup and washoff functions that determine the quality of runoff from each land use 4 Assign a mixture of land uses to each subcatchment area 5 Define pollutant removal functions for nodes within the drainage system that contain treatment facilities We will now apply each of these steps with the exception of number 5 to our example project We will define two runoff pollutants total suspended solids TSS measured as mg L and total Lead measured in ug L In addition we will specify that the concentration of Lead in runoff is a fixed fraction 0 25 of the TSS concentration To add these pollutants to our project 1 Under the Quality category in the Data Browser select the Pollutants sub category beneath it 2 Click the button to add a new pollutant to the project 3 In the Pollutant Editor dialog that appears see Figure 2 17 enter TSS for the pollutant name and leave the other data fields at the
187. lt is 1 Curve name of a Shape Curve in the CURVES section that defines how width varies with depth Tsect name of an entry in the TRANSECTS section that describes the cross section geometry of an irregular channel 231 The CUSTOM shape is a closed conduit whose width versus height is described by a user supplied Shape Curve An IRREGULAR cross section is used to model an open channel whose geometry is described by a Transect object Table D 1 Geometric parameters of conduit cross sections Shape Geoml Geom2 Geom3 Geom4 CIRCULAR Diameter 3 IS FORCE_MAIN Diameter__ Roughness Z FILLED CIRCULAR Diameter Sediment Depth RECT_CLOSED_______ Full Height Top Width RECT_OPEN Full Height Top Width TRIANGULAR Full Height Top Width HORIZ ELLIPSE Full Height Max Width VERT_ELLIPSE Full Height Max Width ARCH standard Size Codet ARCH non standard Full Height Max Width PARABOLIC Full Height Top Width Height Radius Base Width EGG Fulleight HORSESHOE FullHeight GOTHIC Fullfeigt CATENARY FullHeight SEMIELLIPTICAL Full Height BASKETHANDLE Full Height SEMICIRCULAR FullHeight C_factors are used when H W is the FORCE MAIN EQUATION choice in the OPTIONS section while roughness heights in inches or mm are used for D W A circular conduit partially filled with sediment to a specified depth
188. lutants found in a designated routing interface file do not match the names used in the current project inflows and outflows interface files have same name In cases where a run uses one routing interface file to provide inflows for a set of locations and another to save outflow results the two files cannot both have the Same name 261
189. ly of deep well to excessively drained sands or gravels Soils having moderate infiltration rates when thoroughly 0 30 0 15 wetted and consisting chiefly of moderately deep to deep moderately well to well drained soils with moderately fine to moderately coarse textures E g shallow loess sandy loam B C Soils having slow infiltration rates when thoroughly 0 15 0 05 wetted and consisting chiefly of soils with a layer that impedes downward movement of water or soils with moderately fine to fine textures E g clay loams shallow sandy loam D High runoff potential Soils having very slow infiltration 0 05 0 00 rates when thoroughly wetted and consisting chiefly of clay soils with a high swelling potential soils with a permanent high water table soils with a clay pan or clay layer at or near the surface and shallow soils over nearly impervious material 155 A 4 SCS Curve Numbers Hydrologic Soil Group Land Use Description Land Use Description A B c D Cultivated land 8 land Without conservation treatment 12 81 88 91 With conservation treatment Pasture or range land Poor condition 68 79 86 89 Good condition 39 61 74 80 Meadow Good condition 30 58 71 78 Wood or forest land Thin stand poor cover no mulch 45 66 77 83 Good cover 25 55 70 T71 Open spaces lawns parks golf courses cemeteries etc Good condition grass cover on 75 or more of the area 39 61 74 80 Fa
190. m as a series of water and material flows between several major environmental compartments These compartments and the SWMM objects they contain include The Atmosphere compartment from which precipitation falls and pollutants are deposited onto the land surface compartment SWMM uses Rain Gage objects to represent rainfall inputs to the system The Land Surface compartment which is represented through one or more Subcatchment objects It receives precipitation from the Atmospheric compartment in the form of rain or snow it sends outflow in the form of infiltration to the Groundwater compartment and also as surface runoff and pollutant loadings to the Transport compartment The Groundwater compartment receives infiltration from the Land Surface compartment and transfers a portion of this inflow to the Transport compartment This compartment is modeled using Aquifer objects The Transport compartment contains a network of conveyance elements channels pipes pumps and regulators and storage treatment units that transport water to outfalls or to treatment facilities Inflows to this compartment can come from surface runoff groundwater interflow sanitary dry weather flow or from user defined hydrographs The components of the Transport compartment are modeled with Node and Link objects Not all compartments need appear in a particular SWMM model For example one could model just the transport compartment using pre defined hydrograph
191. me Time Value Name name assigned to time series Date date in Month Day Year format e g June 15 2001 would be 6 15 2001 Hour 24 hour military time e g 8 40 pm would be 20 40 relative to the last date specified or to midnight of the starting date of the simulation if no previous date was specified Time hours since the start of the simulation expressed as a decimal number or as hours minutes Value value corresponding to given date and time Multiple date time value or time value entries can appear on a line If more than one line is needed the table s name must be repeated as the first entry on subsequent lines Note that there are two methods for describing the occurrence time of time series data as calendar date time of day which requires that at least one date at the start of the series be entered as elapsed hours since the start of the simulation For the first method dates need only be entered at points in time when a new day occurs Rainfall time series with dates specified Pol 16 190 200L S00 Oak G0 L OO O Om 02 000 0 Tol 0 21 2 001 4700 062 5 2008 0 LA 00D L oO 0 Inflow hydrograph time relative to start of simulation hours can be expressed as decimal hours or hr min BY UY L TOG ao 0 TOs O AZO eo M0 HY o2 30 0 3440 7 DO Go Dor Ol ZA O O 248 s bounding rectangle gt for converting coordinate data from other file Y coordinates for each interior vertex of poly
192. ments Subcatchments can be divided into pervious and impervious subareas Surface runoff can infiltrate into the upper soil zone of the pervious subarea but not through the impervious subarea Impervious areas are themselves divided into two subareas one that contains depression storage and another that does not Runoff flow from one subarea in a subcatchment can be routed to the other subarea or both subareas can drain to the subcatchment outlet 34 Infiltration of rainfall from the pervious area of a subcatchment into the unsaturated upper soil zone can be described using three different models Horton infiltration Green Ampt infiltration SCS Curve Number infiltration To model the accumulation re distribution and melting of precipitation that falls as snow on a subcatchment it must be assigned a Snow Pack object To model groundwater flow between an aquifer underneath the subcatchment and a node of the drainage system the subcatchment must be assigned a set of Groundwater parameters Pollutant buildup and washoff from subcatchments are associated with the Land Uses assigned to the subcatchment The other principal input parameters for subcatchments include assigned rain gage outlet node or subcatchment assigned land uses tributary surface area imperviousness slope characteristic width of overland flow Manning s n for overland flow on both pervious and impervious areas depression storage in both
193. missing To view such a listing select Project gt gt Details from the Main Menu The format of the data in this listing is the same as that used when the file is saved to disk It is described in detail in Appendix D 2 79 This page intentionally left blank 80 CHAPTER 6 WORKING WITH OBJECTS SWMM uses various types of objects to model a drainage area and its conveyance system This section describes how these objects can be created selected edited deleted and repositioned 6 1 Types of Objects SWMM contains both physical objects that can appear on its Study Area Map and non physical objects that encompass design loading and operational information These objects which are listed in the Data Browser and were described in Chapter 3 consist of the following Project Title Notes Links Simulation Options Transects Climatology Controls Rain Gages Pollutants Subcatchments Land Uses Aquifers Curves Snow Packs Time Series Unit Hydrographs Time Patterns Nodes Map Labels 6 2 Adding Objects Visual objects are those that can appear on the Study Area Map and include Rain Gages Subcatchments Nodes Links and Map Labels With the exception of Map Labels there are two ways to add these objects into a project selecting the object s icon from the Object Toolbar and then clicking on the map selecting the object s category in the Data Browser and clicking the Browser s button The first method makes the o
194. mum height of surcharge above node s crown ft or m Minimum depth of surcharge below node s top rim ft or m Note surcharging occurs when water rises above the crown of the highest conduit and only those conduits that surcharge are listed Node Flooding Hours flooded Maximum flooding rate flow units Time of maximum flooding Total flood volume Mgal or Mliter Maximum ponded volume acre in or ha mm Note flooding refers to all water that overflows a node whether it ponds or not and only those nodes that flood are listed Storage Volumes Average volume of water in the facility 1000 ft or 1000 m Average percent of full storage capacity utilized Maximum volume of water in the facility 1000 ft or 1000 m Maximum percent of full storage capacity utilized Time of maximum water stored Maximum outflow rate from the facility flow units Outfall Loading Percent of time that outfall discharges Average discharge flow flow units Maximum discharge flow flow units Total volume of flow discharged Mgal or Mliters Total mass discharged of each pollutant lbs or kg 116 Link Flows Maximum flow flow units Time of maximum flow Maximum velocity ft sec or m sec Ratio of maximum flow to full normal flow Ratio of maximum flow depth to full depth Flow Classification Ratio of adjusted conduit length to actual length Fraction of time spent in the following flow categories dry on both ends dry on t
195. n Purpose Format Remarks WEIRS Identifies each weir link of the drainage system Weirs are used to model flow diversions Name Nodel Node2 Type Offset Cd Flap EC Cd2 Name name assigned to weir link Nodel name of node on inlet side of wier Node2 name of node on outlet side of weir Type TRANSVERSE SIDEFLOW V NOTCH or TRAPEZOIDAL Offset amount that the weir s crest is offset above the invert of inlet node ft or m expressed as either a depth or as an elevation depending on the LINK_OFFSETS option setting Ca weir discharge coefficient for CFS if using US flow units or CMS if using metric flow units Flap YES if flap gate present to prevent reverse flow NO if not default is NO EC number of end contractions for TRANSVERSE or TRAPEZOIDAL weir default 1s 0 Caz discharge coefficient for triangular ends of a TRAPEZOIDAL weir for CFS if using US flow units or CMS if using metric flow units default is value of Ca The geometry of a weir s opening is described in the XSECTIONS section The following shapes must be used with each type of weir Weir Type Cross Section Shape RECT_OPEN RECT_OPEN TRIANGULAR Trapezoidal TRAPEZOIDAL 230 Section OUTLETS Purpose Identifies each outlet flow control device of the drainage system These devices are used to model outflows from storage units or flow diversions that have a user defined relation between flow rate and water depth
196. n Figure 2 2 This will make SWMM automatically label new objects with consecutive numbers following the designated prefix Project Defaults ID Labels subcatchments Nodes Links Rain Gages Lage J Out Subcatchments Junchiors Uu ails Dividers Storage Units Conduits Pumps Regulators IO Increment Save az defaults for all new projects Figure 2 2 Default ID labeling for tutorial example 4 On the Subcatchments page of the dialog set the following default values Area 4 Width 400 Slope 0 5 Imperv 50 N Imperv 0 01 N Perv 0 10 Dstore Imperv 0 05 Dstore Perv 0 05 Zero Imperv 25 Infil Model lt click to edit gt Method Green Ampt Suction Head 3 5 Conductivity 0 5 Initial Deficit 0 26 55 On the Nodes Links page set the following default values Node Invert 0 Node Max Depth 4 Node Ponded Area U Conduit Length 400 Conduit Geometry lt click to edit gt Barrels l Shape Circular Max Depth 1 0 Conduit Roughness 0 01 Flow Units CFS Link Offsets DEPTH Routing Model Kinematic Wave Click OK to accept these choices and close the dialog If you wanted to save these choices for all future new projects you could check the Save box at the bottom of the form before accepting it Next we will set some map display options so that ID labels and symbols will be displayed as we add objects to the study area map and links will have direction arrows r 2 Ss 4 Select View
197. n pre defined as listed in the Macros list box of the dialog to simplify the process of listing the command line parameters When one of these macro symbols is inserted into the list of parameters it will be expanded to its true value when the tool is launched A specific macro symbol can either be typed into the Parameters field or be selected from the Macros list by clicking on it and then added to the parameter list by clicking the button The available macro symbols and their meanings are defined in Table 12 1 below As an example of how the macro expansion works consider the entries in the Tool Properties dialog shown in Figure 12 3 This Spreadsheet Editor tool wants to launch Microsoft Excel and pass 1t the name of the SWMM input data file to be opened by Excel SWMM will issue the following command line to do this c Program Files Microsoft OfficelOfficelO0lEXCEL EXE INPFILE where the string SINPFILE is replaced by the name of a temporary file that SWMM creates internally which will contain the current project s data Table 12 1 Macros Used as Command Line Parameters for External Tools MACRO SYMBOL EXPANDS TO The directory where the current SWMM project file resides The directory where the SWMM 5 executable is installed SINPFILE The name of a temporary file containing the current project s data that is p y g proj created just before the tool is launched SRPTFILE The name of a temporary file that is created ju
198. nches hour a millimeters hour Length feet A Manning s n Maming sn seconds meter seconds meter seconds meter gt Pollutant Buildup mass length mass length mass acre mass hectare Rainfall Intensity inches hour millimeters hour Rainfall Volume inches millimeters Slope Subcatchments percent percent Slope Cross Section rise run o rise run rise run Street Cleaning Interval days days Volume cubic feet cubic meters a meters Width feet 153 A 2 Soil Characteristics Soil Texture Class K Y b FC WP Loamy Sand 1 18 2 40 0 437 0 105 0 047 Sandy Loam 0 43 4 33 0 453 0 190 0 085 Loam 0 13 3 50 0 463 0 232 0 116 Silt Loam 0 26 6 69 0 501 0 284 0 135 Sandy Clay Loam 0 06 8 66 0 398 0 244 0 136 Clay Loam 0 04 8 27 0 464 0 310 0 187 Silty Clay 0 02 11 42 0 479 0 371 0 251 Clay 0 01 12 60 0 475 0 378 0 265 K saturated hydraulic conductivity in hr Y suction head in porosity fraction FC field capacity fraction WP wilting point fraction Source Rawls W J et al 1983 J Hyd Engr 109 1316 154 A 3 NRCS Hydrologic Soil Group Definitions Saturated Hydraulic Group Meaning Conductivity in hr A Low runoff potential Soils having high infiltration rates gt 0 45 even when thoroughly wetted and consisting chief
199. nd Speed page of the Climatology Editor dialog is used to provide average monthly wind speeds These are used when computing snowmelt rates under rainfall conditions Melt rates increase with increasing wind speed Units of wind speed are miles hour for US units and km hour for metric units There are two choices for specifying wind speeds From Climate File Wind speeds will be read from the same climate file that was specified for temperature Monthly Averages Wind speed is specified as an average value that remains constant in each month of the year Enter a value for each month in the data grid provided The default values are all zero Snowmelt Page Climatology Editor Temperature Evaporation Wind Speed Snow Melt Areal Dividing Temperature Between Snow and Fain degrees F AT Weight fractor Negative Melt Ratio fraction Elevation above MSL Feet Latitude degrees Longitude Correction minutes The Snowmelt page of the Climatology Editor dialog is used to supply values for the following parameters related to snow melt calculations Dividing Temperature Between Snow and Rain Enter the temperature below which precipitation falls as snow instead of rain Use degrees F for US units or degrees C for metric units ATI Antecedent Temperature Index Weight This parameter reflects the degree to which heat transfer within a snow pack during non melt periods is affected by prior air temperat
200. nd apeed Gpo Melt Areal Depletion Source of Temperature Data No Data Time Series External Climate File A Start Reading File at ja 172 The Temperature page of the Climatology Editor dialog is used to specify the source of temperature data used for snowmelt computations There are three choices available No Data Time Series External Climate File Select this choice if snowmelt is not being simulated Select this choice if the variation in temperature over the simulation period will be described by one of the project s time series Also enter or select the name of the time series Click the Z button to make the Time Series Editor appear for the selected time series Select this choice if min max daily temperatures will be read from an external climate file Also enter the name of the file or click the Ki button to search for the file If you want to start reading the climate file at a particular date in time that is different than the start date of the simulation as specified in the Simulation Options check off the Start Reading File at box and enter a starting date month day year in the date entry field next to it Evaporation Page Climatology Editor Temperature Evaporation Wind Speed Snow Melt Areall Constant Value inday Time Series From Climate File see Temperat
201. nfiltration concentration units Kdecay first order decay coefficient 1 days Sflag YES if pollutant buildup occurs only when snowfall occurs NO otherwise default 1s NO CoPoll name of co pollutant default is no co pollutant CoFract fraction of co pollutant concentration default is 0 FLOW is areserved word and cannot be used to name a pollutant If pollutant buildup is not restricted to times of snowfall and there is no co pollutant then the last three parameters can be omitted When pollutant X has a co pollutant Y it means that fraction CoFract of pollutant Y s runoff concentration is added to pollutant X s runoff concentration when wash off from a subcatchment is computed 238 Section LANDUSES Purpose Identifies the various categories of land uses within the drainage area Each subcatchment area can be assigned a different mix of land uses Each land use can be subjected to a different street sweeping schedule Format Name SweepInterval Availability LastSweep Remarks Name land use name SweepInterval days between street sweeping Availability fraction of pollutant buildup available for removal by street Sweeping Last Sweep days since last sweeping at start of the simulation Section COVERAGES Purpose Specifies the percentage of a subcatchment s area that is covered by each category of land use Format Subcat Landuse Percent Landuse Percent Remarks Subcat subcatchment name Land
202. ngular ends of a TRAPEZOIDAL weir See the recommended values for V notch weirs listed above End Contractions Number of end contractions fora TRANSVERSE or TRAPEZOIDAL weir whose length is shorter than the channel it is placed in Values will be either 0 1 or 2 depending on if no ends one end or both ends are beveled in from the side walls 169 B 11 Outlet Properties Name User assigned outlet name Inlet Node Name of node on inflow side of outlet Outlet Node Name of node on discharge side of outlet Description Click the ellipsis button or press Enter to edit an optional O SS See of the outlet Tag Optional label used to categorize or Optional label used to categorize or classify the outlet the outlet Offset Depth or elevation of outlet above inlet node invert feet or meters see note below table of Conduit Properties Flap Gate YES if a flap gate exists which prevents backflow through the outlet or NO if no flap gate exists Rating Curve Method of defining flow Q as a function of head h across the outlet A FUNCTIONAL curve uses a power function Q Ah to describe this relation while a TABULAR curve uses a tabulated curve R E flow versus head values FUNCTIONAL Coefficient Se A for the functional relationship between head and flow rate Exponent Exponent B used Exponent B used for the functional relationship between head relationship between head and flow
203. nized It describes the functions of the various menu options and toolbar buttons and how the three main windows the Study Area Map the Browser panel and the Property Editor are used Chapter 5 discusses the project files that store all of the information contained in a SWMM model of a drainage system It shows how to create open and save these files as well as how to set default project options It also discusses how to register calibration data that are used to compare simulation results against actual measurements Chapter 6 describes how one goes about building a network model of a drainage system with EPA SWMM It shows how to create the various physical objects subcatchment areas drainage pipes and channels pumps weirs storage units etc that make up a system how to edit the properties of these objects and how to describe the way that externally imposed inflows boundary conditions and operational controls change over time Chapter 7 explains how to use the study area map that provides a graphical view of the system being modeled It shows how to view different design and computed parameters in color coded fashion on the map how to re scale zoom and pan the map how to locate objects on the map how to utilize a backdrop image and what options are available to customize the appearance of the map Chapter 8 shows how to run a simulation of a SWMM model It describes the various options that control how the analysis is mad
204. nningn Lined Channels Asphalt 0 013 0 017 Brick 0 012 0 018 Concrete 0 011 0 020 Rubble or riprap 10 020 0 035 Vegetal 0 030 0 40 Excavated or dredged Earth straight and uniform 0 020 0 030 Earth winding fairly uniform 0 025 0 040 Rock 0 030 0 045 Unmaintained 0 050 0 140 Natural channels minor streams eS eee width at flood stage lt 100 ft os Fairly regular section regular section 0 030 0 070 030 0 070 Irregular section with pools 0 040 0 100 Source ASCE 1982 Gravity Sanitary Sewer Design and Construction ASCE Manual of Practice No 60 New York NY A 9 Water Quality Characteristics of Urban Runoff Event Mean Constituent Concentrations TSS mg L s CSs CS CSY 180 548 BOD mg L 2 19 COD mg L 82 178 Total P mg L 0 42 0 88 Soluble P mg L 002 NO2 NO3 N mg L Ea Total Cu ug L 43 118 Total Pb ug L 182 443 Total Zn ug L 202 633 Source U S Environmental Protection Agency 1983 Results of the Nationwide Urban Runoff Program NURP Vol 1 NTIS PB 84 185552 Water Planning Division Washington DC 159 This page intentionally left blank 160 APPENDIX B VISUAL OBJECT PROPERTIES B 1 Rain Gage Properties Name User assigned rain gage name X Coordinate Horizontal location of the rain gage on the S
205. node link ID labels and parameter values Symbols turns display of storage unit pump and regulator symbols on off Flow Arrows selects visibility and style of flow direction arrows Background changes color of map s background 98 Map Options Subcatchments Fill Style Clear O Solid Links L 7 Diagonal Cross Hatch Hodes Labels Annotation Symbol Size Symbols Outline Thickness Flow Arrows Background Display link to outlet Subcatchment Options The Subcatchments page of the Map Options dialog controls how subcatchment areas are displayed on the study area map Option Fill Style Symbol Size Outline Thickness Display Link to Outlet Description Selects style used to fill interior of subcatchment area Sets the size of the symbol in pixels placed at the centroid of a subcatchment area Sets the thickness of the line used to draw a subcatchment s boundary set to zero if no boundary should be displayed If checked then a dashed line is drawn between the subcatchment centroid and the subcatchment s outlet node or outlet subcatchment 99 Node Options The Nodes page of the Map Options dialog controls how nodes are displayed on the study area map Option Description Node Size Proportional to Value Display Border Selects node diameter in pixels Select if node size should increase as the viewed parameter increases in value Select if a border should be drawn around each
206. now Pack Editor dialog provides snow melt parameters and initial conditions for snow that accumulates over three different types of areas the impervious area that is plowable 1 e subject to snow removal the remaining impervious area and the entire pervious area The page contains a data entry grid which has a column for each type of area and a row for each of the following parameters Min Melt Coefficient The degree day snow melt coefficient that occurs on December 21 Units are either in hr deg F or mm hr deg C Max Melt Coefficient The degree day snow melt coefficient that occurs on June 21 Units are either in hr deg F or mm hr deg C For a short term simulation of less than a week or so it is acceptable to use a single value for both the minimum and maximum melt coefficients The minimum and maximum snow melt coefficients are used to estimate a melt coefficient that varies by day of the year The latter is used in the following degree day equation to compute the melt rate for any particular day Melt Rate Melt Coefficient Air Temperature Base Temperature Base Temperature Temperature at which snow begins to melt degrees F or C Fraction Free Water Capacity The volume of a snow pack s pore space which must fill with melted snow before liquid runoff from the pack begins expressed as a fraction of snow pack depth Initial Snow Depth Depth of snow at the start of the simulation water equivalent depth in inches or
207. ntionally left blank 104 CHAPTER 8 RUNNING A SIMULATION After a study area has been suitably described its runoff response flow routing and water quality behavior can be simulated This section describes how to specify options to be used in the analysis how to run the simulation and how to troubleshoot common problems that might occur 8 1 Setting Simulation Options SW MM has a number of options that control how the simulation of a stormwater drainage system is carried out To set these options 1 Select the Options category from the Data Browser and then click the Z button 2 A Simulation Options dialog will appear where you can make selections for the following categories of options Simulation Options General Dates Time Steps Dynamic Wave Files Infiltration Model Routing Method Horton None Steady Flow Green Ampl LS Kinematic Wave Curve Number Dynamic wave Miscellaneous Allow Ponding Skip Steady Periods Report Control Actions _ Ignore Rainfall Aunoff Report Input Summary 105 General Options S Date Options Time Step Options Dynamic Wave Routing Options Interface File Options When finished with the dialog click the OK button to accept your choices or the Cancel button to cancel them The following sections discuss each category of options General Options The General page of the Simulation Options dialog sets values fo
208. nts that is available for removal by sweeping the fraction of available buildup for each pollutant removed by sweeping Note that these parameters can be different for each land use and the last parameter can vary also with pollutant 3 3 10 Treatment Removal of pollutants from the flow streams entering any drainage system node is modeled by assigning a set of treatment functions to the node A treatment function can be any well formed mathematical expression involving the pollutant concentration of the mixture of all flow streams entering the node use the pollutant name to represent a concentration the removals of other pollutants use R_ prefixed to the pollutant name to represent removal 91 any of the following process variables FLOW for flow rate into node in user defined flow units DEPTH for water depth above node invert ft or m AREA for node surface area ft or m DT for routing time step sec HRT for hydraulic residence time hours The result of the treatment function can be either a concentration denoted by the letter C or a fractional removal denoted by R For example a first order decay expression for BOD exiting from a storage node might be expressed as C BOD exp 0 05 HRT or the removal of some trace pollutant that is proportional to the removal of total suspended solids TSS could be expressed as R 0 75 R_TSS 3 3 11 Curves Curve objects are used to describe a functi
209. nu Project Title Notes Sele Tutorial Example Use tithe line as header for printing Figure 2 8 Title Notes Editor 2 5 Running a Simulation Setting Simulation Options Before analyzing the performance of our example drainage system we need to set some options that determine how the analysis will be carried out To do this 1 From the Data Browser select the Options category and click the Z button 2 On the General page of the Simulation Options dialog that appears see Figure 2 9 select Kinematic Wave as the flow routing method The infiltration method should already be set to Green Ampt The Allow Ponding option should be unchecked 3 On the Dates page of the dialog set the End Analysis time to 12 00 00 4 Onthe Time Steps page set the Routing Time Step to 60 seconds 5 Click OK to close the Simulation Options dialog 16 Simulation Options General Dates Time Steps Dynamic Wave Files Infiltration Model Routing Method Horton None Steady Flow Green Ampl 2 Kinematic Wave Curve Number Dynamic Wave Miscellaneous Allow Ponding Skip Steady Periods Report Control Actions _ Ignore Rainfall Runoff Report Input Summary Figure 2 9 Simulation Options dialog Running a Simulation We are now ready to run the simulation To do so select Project gt gt Run Simulation or click the button If there was a problem with the simulation a Status
210. number of decimal places to use when displaying computed results for the parameter Note that the number of decimal places displayed for any particular input design parameter such as slope diameter length etc is whatever the user enters 71 This page intentionally left blank 72 CHAPTER 5 WORKING WITH PROJECTS Project files contain all of the information used to model a study area They are usually named with a INP extension This section describes how to create open and save EPA SWMM projects as well as setting their default properties 5 1 Creating a New Project To create a new project 1 Select File gt gt New from the Main Menu or click E on the Standard Toolbar 2 You will be prompted to save the existing project 1f changes were made to it before the new project is created 3 A new unnamed project is created with all options set to their default values A new project is automatically created whenever EPA SWMM first begins Y If you are going to use a backdrop image with automatic area and length calculation then it is recommended that you set the map dimensions immediately after creating the new project see Setting the Map s Dimensions 5 2 Opening an Existing Project To open an existing project stored on disk 1 Either select File gt gt Open from the Main Menu or click gt on the Standard Toolbar 2 You will be prompted to save the current project if changes were made to it 3 Select
211. nvert E El Invert elevation of the outfall Invert elevation of the outfall feet or meters or meters Tide Gate YES tide gate present to prevent backflow NO no tide gate present Type Type of outfall boundary condition FREE outfall stage determined by minimum of critical flow depth and normal flow depth in the connecting conduit NORMAL outfall stage based on normal flow depth in connecting conduit FIXED outfall stage set to a fixed value TIDAL outfall stage given by a table of tide elevation versus time of day TIMESERIES outfall stage supplied from a time series of elevations Fixed Fixed Stage Water elevation for a FIXED type of outfall Water elevation for a FIXED type of outfall feet or meters or meters Tidal Curve Name of the Tidal Curve relating water elevation to hour of the Name day for a TIDAL outfall double click to edit the curve Time Series Name of time series containing time history of outfall elevations Name fora TIMESERIES outfall double click to edit the series 164 B 5 Flow Divider Properties Name User assigned divider name X Coordinate Horizontal location of the divider on the Study Area Map If left blank then the divider will not appear on the map Y Coordinate Vertical location of the divider on the Study Area Map If left blank then the divider will not appear on the map Description Click the ellipsis button or press Enter to edit an optional description of the di
212. o select an object on the map Enables the user to select the vertex of a subcatchment or link Enables the user to delineate a region on the map for selecting multiple objects Selects all objects when the map is the active window or all cells of a table when a tabular report is the active window Locates a specific object by name on the map Locates specific text in a Status Report Edits a property for the group of objects that fall within the outlined region of the map Deletes a group of objects that fall within the outlined region of the map The View Menu contains commands for viewing the Study Area Map Command Dimensions Backdrop Pan Zoom In Zoom Out Full Extent Query Overview Objects Legends Toolbars Description Sets reference coordinates and distance units for the study area map Allows a backdrop image to be added positioned and viewed Pans across the map Zooms in on the map Zooms out on the map Redraws the map at full extent Highlights objects on the map that meet specific criteria Toggles the display of the Overview Map Toggles display of classes of objects on the map Controls display of the map legends Toggles display of tool bars 61 Project Menu The Project menu contains commands related to the current project being analyzed Command Summary Details Defaults Calibration Data Run Simulation Report Menu Description Lists the number of each type of object in the project
213. o use the dialog Group Editor For objects of type subcatchment hs C with Tag equal to y Oe edit the property 1 Select a class of object Subcatchments Infiltration Junctions Storage Units or Conduits to edit 2 Check the with Tag equal to box if you want to add a filter that will limit the objects selected for editing to those with a specific Tag value For Infiltration the Tag will be that of the subcatchment to which the infiltration parameters belong 87 3 Enter a Tag value to filter on if you have selected that option 4 Select the property to edit 5 Select whether to replace multiply or add to the existing value of the property Note that for some non numerical properties the only available choice is to replace the value 6 In the lower right edit box enter the value that should replace multiply or be added to the existing value for all selected objects Some properties will have an ellipsis button displayed in the edit box which should be clicked to bring up a specialized editor for the property 7 Click OK to execute the group edit To delete the objects located within a selected area of the map select Edit gt gt Group Delete from the Main Menu Then select the categories of objects you wish to delete from the dialog box that appears As an option you can specify that only objects within the selected area that have a specific Tag property should be deleted Keep in mind that deleting a n
214. ode will also delete any links connected to the node 88 CHAPTER 7 WORKING WITH THE MAP EPA SWMM can display a map of the study area being modeled This section describes how you can manipulate this map to enhance your visualization of the system 7 1 Selecting a Map Theme A map theme displays object properties in color coded fashion on the Study Area Map The dropdown list boxes on the Map Browser are used for selecting a theme to display for Subcatchments Nodes and Links SWMM 5 Example1 inp File Edit Window Help Toals view Project Report Hap Data Themes Subcatchments Aunaft ral G GL T wo 4 Depth Links Flow I Methods for changing the color coding associated with a theme are discussed in Section 7 9 below 7 2 Setting the Map s Dimensions The physical dimensions of the map can be defined so that map coordinates can be properly scaled to the computer s video display To set the map s dimensions 1 Select View gt gt Dimensions from the Main Menu 2 Enter coordinates for the lower left and upper right corners of the map into the Map Dimensions dialog see below that appears or click the Auto Size button to automatically set the dimensions based on the coordinates of the objects currently included in the map 3 Select the distance units to use for these coordinates 89 4 Ifthe Auto Length option is in effect check the Re compute a
215. of drainage elements such as storage units flow dividers pumps and regulators to model more complex types of systems using control rules to simulate real time operation of pumps and regulators employing different types of externally imposed inflows at drainage system nodes such as direct time series inflows dry weather inflows and rainfall derived infiltration inflow modeling groundwater interflow between aquifers beneath subcatchment areas and drainage system nodes modeling snow fall accumulation and melting within subcatchments adding calibration data to a project so that simulated results can be compared with measured values utilizing a background street site plan or topo map to assist in laying out a system s drainage elements and to help relate simulated results to real world locations You can find more information on these and other features in the remaining chapters of this manual 31 This page intentionally left blank 32 CHAPTER 3 SWMM s CONCEPTUAL MODEL This chapter discusses how SWMM models the objects and operational parameters that constitute a stormwater drainage system Details about how this information is entered into the program are presented in later chapters An overview is also given on the computational methods that SWMM uses to simulate the hydrology hydraulics and water quality transport behavior of a drainage system 3 1 Introduction SWMM conceptualizes a drainage syste
216. oject s data will be replaced with the data contained in the updated temporary input file If the SOUTFILE macro was used as a command line parameter and its corresponding file is found to contain a valid set of output results after the tool closes then the contents of this file will be used to display simulation results within the SWMM workspace Generally speaking the suppliers of third party tools will provide instructions on what settings should be used in the Tool Properties dialog to properly register their tool with SWMM 151 This page intentionally left blank 152 APPENDIX A USEFUL TABLES A 1 Units of Measurement PARAMETER USCUSTOMARY SIMETRIC Area Subcatchment acres hectares Area Storage Unit square feet Square meters Area Ponding square feet Square meters Capillary Suction inches millimeters Concentration mg L mg L ug L ug L Count L Count L Decay Constant Infiltration 1 hours 1 hours Decay Constant Pollutants l days l days Depression Storage inches its inches millimeters Depth feet meters Diameter feet meters Discharge Coefficient Orifice dimensionless dimensionless Weir CFS foot CMS meter Elevation feet meters Evaporation inches day millimeters day Flow CFS CMS GPM LPS MGD MLD Head feet meters Hydraulic Conductivity inches hour inches hour millimeters hour Infiltration Rate i
217. on slope 1 e head loss per unit length depending on the flow routing method used For pipes with Circular Force Main cross sections either the Hazen Williams or Darcy Weisbach formula is used in place of the Manning equation for fully pressurized flow For U S units the Hazen Williams formula is O 1318CAR STA where C is the Hazen Williams C factor which varies inversely with surface roughness and is supplied as one of the cross section s parameters The Darcy Weisbach formula is O z 188 png f where g is the acceleration of gravity and f is the Darcy Weisbach friction factor For turbulent flow the latter is determined from the height of the roughness elements on the walls of the pipe supplied as an input parameter and the flow s Reynolds Number using the Colebrook White equation The choice of which equation to use is a user supplied option Y A conduit does not have to be assigned a Force Main shape for it to pressurize Any of the closed cross section shapes can potentially pressurize and thus function as force mains that use the Manning equation to compute friction losses The principal input parameters for conduits are names of the inlet and outlet nodes offset height or elevation above the inlet and outlet node inverts conduit length Manning s roughness cross sectional geometry entrance exit losses optional presence of a flap gate to prevent reverse flow optional 39 3 2 8 Pumps
218. onal relationship between two quantities The following types of curves are available in SWMM Storage describes how the surface area of a Storage Unit node varies with water depth Shape describes how the width of a customized cross sectional shape varies with height for a Conduit link Diversion relates diverted outflow to total inflow for a Flow Divider node Tidal describes how the stage at an Outfall node changes by hour of the day Pump relates flow through a Pump link to the depth or volume at the upstream node or to the head delivered by the pump Rating relates flow through an Outlet link to the head difference across the outlet Control determines how the control setting of a pump or flow regulator varies as a function of some control variable such as water level at a particular node as specified in a Modulated Control rule Each curve must be given a unique name and can be assigned any number of data pairs 3 3 12 Time Series Time Series objects are used to describe how certain object properties vary with time Time series can be used to describe temperature data evaporation data rainfall data water stage at outfall nodes 52 external inflow hydrographs at drainage system nodes external inflow pollutographs at drainage system nodes control settings for pumps and flow regulators Each time series must be given a unique name and can be assigned any number of time value data
219. onduit is on the same order as the routing time step The concentration of a constituent exiting the conduit at the end of a time step is found by integrating the conservation of mass equation using average values for quantities that might change over the time step such as flow rate and conduit volume Water quality modeling within storage unit nodes follows the same approach used for conduits For other types of nodes that have no volume the quality of water exiting the node is simply the mixture concentration of all water entering the node 58 CHAPTER 4 SWMM S MAIN WINDOW This chapter discusses the essential features of SWMM s workspace It describes the main menu bar the tool and status bars and the three windows used most often the Study Area Map the Browser and the Property Editor It also shows how to set program preferences 4 1 Overview The EPA SWMM main window is pictured below It consists of the following user interface elements a Main Menu several Toolbars a Status Bar the Study Area Map window a Browser panel and a Property Editor window A description of each of these elements is provided in the sections that follow SWEM 5 Frampled inp He Ede Wea Prez Report Tos ide Heb DESEA TWEE EPR A RER POB TRB T Chata Hap Hn daz s Ann lagos SE G perra Pale lt Show Packs Jig FH idiegiapi Haja Alice Ling Landak B mea 4 WDE Uul iii Trane Ka 41009 on
220. ooth asphalt 0 011 Smooth concrete 0 012 Ordinary concrete lining 0 013 Good wood 0014 Brick with cement mortar 10 014 Vitrified clay 0015 Cast iron 0 015 Corrugated metal pipes 0 024 Cement rubble surface Cement rubble surface 10 024 0 024 Fallow soils no residue Fallow soils no residue 0 05 0 05 Cultivated soils Residue cover lt 20 0 06 Residue cover gt 20 PE 17 Range natural 10 13 13 Grass Short prarie 0 15 Dense 0 24 Bermuda grass 0 41 Woods Light underbrush 0 40 Dense underbrush 0 80 Source McCuen R et al 1996 Hydrology FHWA SA 96 067 Federal Highway Administration Washington DC 157 A 7 Manning s n Closed Conduits Conduit Material Manning n Asbestos cement pipe 0 011 0 015 Brick 0 013 0 017 Cast iron pipe Cement lined amp seal coated 0 011 0 015 Concrete monolithic Smooth forms 0 012 0 014 Rough forms 0 015 0 017 Concrete pipe 0 011 0 015 Corrugated metal pipe 1 2 1n x 2 2 3 1n corrugations Plain 0 022 0 026 Paved invert 0 018 0 022 Spun asphalt lined 0 011 0 015 Plastic pipe smooth 0 011 0 015 Vitrified clay Pipes 0 011 0 015 Liner plates 0 013 0 017 Source ASCE 1982 Gravity Sanitary Sewer Design and Construction ASCE Manual of Practice No 60 New York NY 158 A 8 Manning s n Open Channels Channel Type Ma
221. or an outfall for a flow divider El fora storage unit 2 Move the mouse to the desired location on the map and click To add a Node using the Data Browser 1 Select the type of node Junction Outfall Flow Divider or Storage Unit from the categories list of the Data Browser 2 Click the Y button 3 Enter the node s X and Y coordinates in the Property Editor if you want it to appear on the study area map Adding a Link To add a Link using the Object Toolbar 1 Click the button corresponding to the type of link to add if its not already depressed for a Conduit 82 LP fora Pump 19 for an Orifice t for a Weir LF for an Outlet 2 On the study area map click the mouse on the link s inlet upstream node 3 Move the mouse in the direction of the link s outlet downstream node clicking at all intermediate points needed to define the link alignment 4 Click the mouse a final time over the link s outlet downstream node Pressing the right mouse button or the lt Esc gt key while drawing a link will cancel the operation To add a Link using the Data Browser 1 Select the type of link to add from the categories listed in the Data Browser 2 Click the Y button 3 Enter the names of the inlet and outlet nodes of the link in the Property Editor Adding a Map Label To add a text label to the Study Area Map Click the Text button T on the Object Toolbar Click the mouse on the map where the top l
222. ose areas Input loadings of pollutants to the drainage system can also originate from external time series inflows as well as from dry weather inflows 3 3 9 Land Uses Land Uses are categories of development activities or land surface characteristics assigned to subcatchments Examples of land use activities are residential commercial industrial and undeveloped Land surface characteristics might include rooftops lawns paved roads undisturbed soils etc Land uses are used solely to account for spatial variation in pollutant buildup and washoff rates within subcatchments The SWMM user has many options for defining land uses and assigning them to subcatchment areas One approach is to assign a mix of land uses for each subcatchment which results in all land uses within the subcatchment having the same pervious and impervious characteristics Another approach is to create subcatchments that have a single land use classification along with a distinct set of pervious and impervious characteristics that reflects the classification 49 The following processes can be defined for each land use category pollutant buildup pollutant washoff street cleaning Pollutant Buildup Pollutant buildup that accumulates within a land use category is described or normalized by either a mass per unit of subcatchment area or per unit of curb length Mass is expressed in pounds for US units and kilograms for metric units The amount of buil
223. ow continuity errrors the names of the conduits that most often determined the size of the time step used for flow routing only when the Variable Time Step option is used the names of the links with the highest Flow Instability Index values information on the range of routing time steps taken and the percentage of these that were considered steady state In addition the report contains several tables that display summary results for the quantities of most interest for each subcatchment node and link The tables and the information they display are listed below 115 Subcatchment Runoff Total precipitation in or mm Total run on from other subcatchments in or mm Total evaporation in or mm Total infiltration in or mm Total runoff depth in or mm Total runoff volume Mgal or Mliters Runoff coefficient ratio of total runoff to total precipitation Subcatchment Washoff Total mass of each pollutant washed off the subcatchment Ibs or kg Node Depths Average water depth ft or m Maximum water depth ft or m Maximum hydraulic head HGL elevation ft or m Time of maximum depth Node Inflows Maximum lateral inflow flow units Maximum total inflow flow units Time of maximum total inflow Total lateral inflow volume Mgal or Mliters Total inflow volume Mgal or Mliters Note Total inflow consists of lateral inflow plus inflow from connecting links Node Surcharging Hours surcharged Maxi
224. owing expression that relates surface area ft2 or m2 to water depth ft or m for a storage unit with FUNCTIONAL geometry Area AO AL se Depth 227 Section Purpose Format Remarks CONDUITS Identifies each conduit link of the drainage system Conduits are pipes or channels that convey water from one node to another Name Name Nodel Node2 Length N Al a Q0 Nodel NodeZ Length N Z1 Z2 00 name assigned to conduit link name of upstream node name of downstream node conduit length ft or m value of n 1 e roughness parameter in Manning s equation offset of upstream end of conduit invert above the invert elevation of its upstream node ft or m offset of downstream end of conduit invert above the invert elevation of its downstream node ft or m flow in conduit at start of simulation flow units default is 0 The figure below illustrates the meaning of the 21 and Z2 parameters lt gt gt These offsets are expressed as a relative distance above the node invert if the LINK_OFFSETS option is set to DEPTH the default or as an absolute elevation if it is set to ELEVATION 228 Section PUMPS Purpose Identifies each pump link of the drainage system Format Name Nodel Node2 Pcurve Status Startup Shutoff Remarks Name name assigned to pump link Nodel name of node on inlet side of pump Node2 name of node on outlet side of pump Pcurve name of pump curve
225. ox whenever the mouse is placed over an object on the study area map Confirm Deletions Check to display a confirmation dialog box before deleting any object Automatic Backup File Check to save a backup copy of a newly opened project to disk named with a bak extension Report Elapsed Time by Check to use elapsed time rather than date time as Default the default for time series graphs and tables Prompt to Save Results If left unchecked then simulation results are automatically saved to disk when the current project is closed Otherwise the user will be asked if results should be saved Clear File List Check to clear the list of most recently used files that appears when File gt gt Reopen is selected from the Main Menu Temporary Directory Name of the directory folder where EPA SWMM writes its temporary files Y The Temporary Directory must be a file directory folder where the user has write privileges and must have sufficient space to temporarily store files which can easily grow to several tens of megabytes for larger study areas and simulation runs The original default is the folder where Windows writes 1ts temporary files Number Format Preferences The Number Formats page of the Preferences dialog controls the number of decimal places displayed when simulation results are reported Use the dropdown list boxes to select a specific Subcatchment Node or Link parameter and then use the edit boxes next to them to select the
226. parameters Subcatchment Runoff Subcatchment Pollutant Washoff Groundwater Flow Groundwater Elevation Snow Pack Depth Node Depth Node Lateral Inflow T7 Node Flooding Node Water Quality Link Flow Rate The format of the file is described in Section 11 5 Registering Calibration Data To register calibration data residing in a Calibration File i Zi Select Project gt gt Calibration Data from the Main Menu In the Calibration Data dialog form shown below click in the box next to the parameter e g node depth link flow etc whose calibration data will be registered Either type in the name of a Calibration File for this parameter or click the Browse button to search for it Click the Edit button if you want to open the Calibration File in Windows NotePad for editing Repeat steps 2 4 for any other parameters that have calibration data Click OK to accept your selections Calibration Data Calibration Y anaie Mame of Calibration File Subcatchment Runott Subcatchment VWashott Node Water Depth Link Flow Rate CMe Projects S MME 0 ReporExtanteztranl dat Node Water Duality Node Lateral Inflow 78 5 8 Viewing All Project Data A listing of all project data with the exception of map coordinates can be viewed in a non editable window formatted for input to SWMM s computational engine This can be useful for checking data consistency and to make sure that no key components are
227. pervious and impervious areas percent of impervious area with no depression storage 3 2 3 Junction Nodes Junctions are drainage system nodes where links join together Physically they can represent the confluence of natural surface channels manholes in a sewer system or pipe connection fittings External inflows can enter the system at junctions Excess water at a junction can become partially pressurized while connecting conduits are surcharged and can either be lost from the system or be allowed to pond atop the junction and subsequently drain back into the junction The principal input parameters for a junction are invert elevation height to ground surface ponded surface area when flooded optional external inflow data optional 35 3 2 4 Outfall Nodes Outfalls are terminal nodes of the drainage system used to define final downstream boundaries under Dynamic Wave flow routing For other types of flow routing they behave as a junction Only a single link can be connected to an outfall node The boundary conditions at an outfall can be described by any one of the following stage relationships the critical or normal flow depth in the connecting conduit a fixed stage elevation a tidal stage described in a table of tide height versus hour of the day auser defined time series of stage versus time The principal input parameters for outfalls include invert elevation boundary condition type and st
228. ponse ratios for the short term intermediate term and long term UH responses respectively TIL F E time to peak hours for the short term intermediate term and long term UH responses respectively Kel ee K3 recession limb ratios for short term intermediate term and long term UH responses respectively For each group of unit hydrographs use one line to specify its rain gage followed by one or more lines containing UH shape parameters for months with RDII flow Months not listed are assumed to have no RDII The response ratios R are the fraction of a unit of rainfall depth that becomes RDII The sum of the ratios for the three UH s do not have to equal 1 0 The recession limb ratios K are the ratio of the duration of the UH recession limb to the time to peak T making the UH time base T 1 K hours The area under each UH is 1 inch or mm All UH sets in this group have the same shapes except those in July YHLOL RGI WELO ALi 04033 TSU DeUe 210 JALOL JUL Osso 20 25 SS Oi 1 LE 22 O Za DI O OF 2 Or 02033 Zl OO tet 00 T Dis 246 Section Purpose Format Remarks Examples CURVES Describes a relationship between two variables in tabular format Name Type X value Y value Name name assigned to table Type STORAGE SHAPE DIVERSION TIDAL PUMP1 PUMP2 PUMP3 PUMP4 RATING CONTROL X value an x independent variable value Y value the y dependent variable value correspondin
229. ppear see Figure 2 6 3 Select Subcatchment as the type of object to edit Rain Gage as the property to edit and type in Gagel as the new value 4 Click OK to change the rain gage of all subcatchments to Gagel A confirmation dialog will appear noting that 3 subcatchments have changed Select No when asked to continue editing 13 Group Editor For objects of type sUbcatchmernt N C with Tag equal te OE edit the property pd Figure 2 6 Group Editor dialog Because the outlet nodes vary by subcatchment we must set them individually as follows 1 Double click on subcatchment S or select 1t from the Data Browser and click the Browser s 1 button to bring up the Property Editor 2 Type J in the Outlet field and press Enter Note how a dotted line is drawn between the subcatchment and the node 3 Click on subcatchment 52 and enter J2 as its Outlet 4 Click on subcatchment S3 and enter J3 as its Outlet We also wish to represent area S3 as being less developed than the others Select S3 into the Property Editor and set its Imperviousness to 25 The junctions and outfall of our drainage system need to have invert elevations assigned to them As we did with the subcatchments select each junction individually into the Property Editor and set its Invert Elevation to the value shown below Node Invert JI 96 J2 90 J3 93 J4 SS Out 85 Only one of the conduits in our example system has a non defa
230. ppear in any arbitrary order in the input file and not all sections must be present Each section can contain one or more lines of data Blank lines may appear anywhere in the file A semicolon can be used to indicate that what follows on the line is a comment not data Data items can appear in any column of a line Observe how in Figure D 1 these features were used to create a tabular appearance for the data complete with column headings Section keywords can appear in mixed lower and upper case and only the first four characters plus the open bracket are used to distinguish one keyword from another e g DIVIDERS and Divi are equivalent An option is available in the OPTIONS section to choose flow units from among cubic feet per second CFS gallons per minute GPM million gallons per day MGD cubic meters per second CMS liters per second LPS or million liters per day MLD If cubic feet or gallons are chosen for flow units then US units are used for all other quantities If cubic meters or liters are chosen then metric units apply to all other quantities The default flow units are CFS A detailed description of the data in each section of the input file will now be given When listing the format of a line of data mandatory keywords are shown in boldface while optional items appear in parentheses A list of keywords separated by a slash YES NO means that only one of the words should appear in the data line 210
231. putational Methods SWMM is a physically based discrete time simulation model It employs principles of conservation of mass energy and momentum wherever appropriate This section briefly describes the methods SWMM uses to model stormwater runoff quantity and quality through the following physical processes Surface Runoff Infiltration Groundwater Snowmelt Flow Routing Surface Ponding Water Quality Routing 93 3 4 1 Surface Runoff The conceptual view of surface runoff used by SWMM is illustrated in Figure 3 5 below Each subcatchment surface is treated as a nonlinear reservoir Inflow comes from precipitation and any designated upstream subcatchments There are several outflows including infiltration evaporation and surface runoff The capacity of this reservoir is the maximum depression storage which is the maximum surface storage provided by ponding surface wetting and interception Surface runoff per unit area Q occurs only when the depth of water in the reservoir exceeds the maximum depression storage d in which case the outflow is given by Manning s equation Depth of water over the subcatchment d in feet is continuously updated with time t in seconds by solving numerically a water balance equation over the subcatchment RAINFALL EVAPORATION SNOWMELT d Laja INFILTRATION Figure 3 5 Conceptual view of surface runoff T d l 3 4 2 Infiltration Infiltration is the process of rainfal
232. r by using a text editor It contains six lines with the following information Line 1 real world width of a pixel in the horizontal direction Line 2 X rotation parameter not used Line 3 Y rotation parameter not used Line 4 negative of the real world height of a pixel in the vertical direction 91 Line 5 real world X coordinate of the upper left corner of the image Line 6 real world Y coordinate of the upper left corner of the image If no world file is specified then the backdrop will be scaled to fit into the center of the map display window Scale Map to Backdrop Image This option is only available when a world file has been specified Selecting it forces the dimensions of the Study Area Map to coincide with those of the backdrop image In addition all existing objects on the map will have their coordinates adjusted so that they appear within the new map dimensions yet maintain their relative positions to one another Selecting this option may then require that the backdrop be re aligned so that its position relative to the drainage area objects is correct How to do this is described below The backdrop image can be re positioned relative to the drainage system by selecting View gt gt Backdrop gt gt Align This allows the backdrop image to be moved across the drainage system by moving the mouse with the left button held down until one decides that it lines up properly The backdrop image can also be resized
233. r line to be defined by supplying a Shape Curve for the cross section see Section 3 3 11 below 37 Table 3 1 Available cross section shapes for conduits Name Parameters Shape Name Parameters Circular Full Height Circular Force Full Height Main Roughness Filled Full Height Rectangular Full Height Circular Filled Depth Closed Width Rectangular Full Height Trapezoidal Full Height Open Width Base Width Side Slopes Triangular Full Height Horizontal Full Height Top Width YW Ellipse Max Width Arch Full Height Max Width Power Full Height Top Width Exponent Rectangular Round Vertical Full Height Ellipse Max Width Parabolic Full Height Top Width Rectangular Full Height Triangular Top Width Triangle Height Modified Full Height Baskethandle Top Width Full Height Top Width Bottom Radius o o Catenary Full Height Semi Full Height Elliptical Baskethandle Full Height Semi Circular Full Height Irregular Transect Custom Full Height Coordinates w Closed Shape Shape Curve Coordinates o Natural Channel SWMM uses the Manning equation to express the relationship between flow rate Q cross sectional area A hydraulic radius R and slope in all conduits For standard U S units 149 n O ET S where n is the Manning roughness coefficient The slope S is interpreted as either the conduit slope or the fricti
234. r quality for all categories Event Time Period Select the length of the time period that defines an event The choices are daily monthly or event dependent In the latter case the event period depends on the number of consecutive reporting periods where simulation results are above the threshold values defined below 131 Statistic Choose an event statistic to be analyzed The available choices depend on the choice of variable to be analyzed and include such quantities as mean value peak value event total event duration and inter event time i e the time interval between the midpoints of successive events For water quality variables the choices include mean concentration peak concentration mean loading peak loading and event total load Event Thresholds These define minimum values that must be exceeded for an event to occur The Analysis Variable threshold specifies the minimum value of the variable being analyzed that must be exceeded for a time period to be included in an event The Event Volume threshold specifies a minimum flow volume or rainfall volume that must be exceeded for a result to be counted as part of an event Separation Time sets the minimum number of hours that must occur between the end of one event and the start of the next event Events with fewer hours are combined together This value applies only to event dependent time periods not to daily or monthly event periods If a particula
235. r the following options Infiltration Model This option controls how infiltration of rainfall into the upper soil zone of subcatchments is modeled The choices are Horton Green Ampt Curve Number Changing this option will require re entering values for the infiltration parameters in each subcatchment Routing Method This option determines which method is used to route flows through the conveyance system The choices are None Steady Flow Kinematic Wave Dynamic Wave Choose None to simulate runoff only Allow Ponding Checking this option will allow excess water to collect atop nodes and be re introduced into the system as conditions permit In order for ponding to actually occur at a particular node a non zero value for its Ponded Area attribute must be used Report Control Actions Check this option if you want the simulation s Status Report to list all discrete control actions taken by the Control Rules associated with a project continuous modulated control actions are not listed This option should only be used for short term simulation Report Input Summary Check this option if you want the simulation s Status Report to list a summary of the project s input data 106 Skip Steady State Periods Checking this option will make the simulation use the most recently computed conveyance system flows during a steady state period instead of computing a new flow routing solution A time step 1s cons
236. r type of threshold does not apply then leave the field blank After the choices made on the Statistics Selection dialog form are processed a Statistics Report is produced as shown below Statistics Subcatch 51 Rainfall Summary Events SUMMARY Variable Event Event Event Event Event Statistic Threshold Threshold Threshold Period of Record E Histogram Frequency Plot STATISTICS Subcatch 51 Painfall In hE Lin hr Paintftall 0 00 ins hr Event Volume 0 00 ir Inter Erent Time gt 6 0 hr 1 0101 1922 to 01fsO02 lt 2000 Number of Events Event Frequency Minimim Value Maximum Value Mean Value std Dewiation Skemess Coeff Fraction of all 076 010 500 059 059 367 reporting periods belonging to an event 132 EJ The report consists of four tabbed pages that contain a table of event summary statistics a table of rank ordered event periods including their date duration and magnitude a histogram plot of the chosen event statistic an exceedance frequency plot of the event values Note that the exceedance frequencies included in the report are computed with respect to the number of events that occur not the total number of reporting periods 133 This page intentionally left blank 134 CHAPTER 10 PRINTING AND COPYING This chapter describes how to print copy to the Windows clipboard or copy to file the contents of the currently a
237. rage and outflow capacity flow units concentration of each pollutant after any treatment applied at the node mass liter Viewing Results on the Map Link Variables flow rate flow units average water depth ft or m flow velocity ft sec or m sec Froude number dimensionless capacity ratio of depth to full depth concentration of each pollutant mass liter System Wide Variables air temperature degrees F or C total rainfall 1n hr or mm hr total snow depth inches or millimeters average losses in hr or mm hr total runoff flow flow units total dry weather inflow flow units total groundwater inflow flow units total I amp I inflow flow units total direct inflow flow units total external inflow flow units total surface flooding flow units total outflow from outfalls flow units total nodal storage volume ft3 or m3 There are several ways to view the values of certain input parameters and simulation results directly on the Study Area Map For the current settings on the Map Browser the subcatchments nodes and links of the map will be colored according to their respective Map Legends The map s color coding will be updated as a new time period is selected in the Map Browser 118 When the Flyover Map Labeling program preference is selected see Section 4 9 moving the mouse over any map object will display its ID name and the value of its current theme parameter in a hint s
238. ration rates vary with time for the study area CONSTANT evap MONTHLY evapl evap2 evapl2 TIMESERIES Tseries FILE Pant panZ ass paniz evap constant evaporation rate in day or mm day evapl evaporation rate in January in day or mm day evap12 evaporation rate in December in day or mm day Tseries name of time series in TIMESERIES section with evaporation data panl pan coefficient for January peniZ pan coefficient for December Use only one of the above formats If no EVAPORATION section appears then evaporation is assumed to be 0 FILE indicates that evaporation data will be read from the same external climate file used for air temperatures see below 218 Section Purpose Formats Remarks TEMPERATURE Specifies daily air temperatures monthly wind speed and various snowmelt parameters for the study area Required only when snowmelt is being modeled or when evaporation rates are read from an external climate file TIMESERIES Tseries FILE Fname Start WINDSPEED MONTHLY si s2 sll s12 WINDSPEED FILE SNOWMELT Stemp ATIwt RNM Elev Lat DTLong ADC IMPERVIOUS f O f 1 8 f 9 ADC PERVIOUS ESO sre pee dag Tseries name of time series in TIMESERIES section with temperature data Fname name of external Climate file with temperature data Sea rE date to begin reading from the file in month day year format default is the beginning of the file sl average wind speed in January mph or km
239. rent link variable Check to display text with a transparent background otherwise an opaque background is used Adjusts the size of the font used to display annotation Selects minimum zoom at which annotation should be displayed all annotation will be hidden at zooms smaller than this The Symbols page of the Map Options dialog determines which types of objects are represented with special symbols on the map Option Description Display Node Symbols If checked then special node symbols will be used Display Link Symbols If checked then special link symbols will be used At Zoom Of Flow Arrow Options Selects minimum zoom at which symbols should be displayed symbols will be hidden at zooms smaller than this The Flow Arrows page of the Map Options dialog controls how flow direction arrows are displayed on the map Option Arrow Style Arrow Size At Zoom Of Description Selects style shape of arrow to display select None to hide arrows Sets arrow size Selects minimum zoom at which arrows should be displayed arrows will be hidden at zooms smaller than this 101 Y Flow direction arrows will only be displayed after a successful simulation has been made and a computed parameter has been selected for viewing Otherwise the direction arrow will point from the user designated start node to end node Background Options The Background page of the Map Options dialog offers a selection of colors used to paint the
240. rfaces more than rapid flow over pavement for example Adjustments should be made to the width parameter to produce good fits to measured runoff hydrographs Slope Average percent slope of the subcatchment Imperv Percent of land area which is impervious N Imperv Manning s n for overland flow over the impervious portion of the subcatchment see Section A 6 for typical values N Perv Manning s n for overland flow over the pervious portion of the subcatchment see Section A 6 for typical values Dstore Imperv Depth of depression storage on the impervious portion of the subcatchment inches or millimeters see Section A 5 for typical values Dstore Perv Depth of depression storage on the pervious portion of the subcatchment inches or millimeters see Section A 5 for typical values Zero Imperv Percent of the impervious area with no depression storage Subarea Routing Choice of internal routing of runoff between pervious and impervious areas IMPERYV runoff from pervious area flows to impervious area PERV runoff from impervious area flows to pervious area OUTLET runoff from both areas flows directly to outlet 162 Percent Routed Percent of runoff routed between subareas Infiltration Click the ellipsis button or press Enter to edit infiltration parameters for the subcatchment Groundwater Click the ellipsis button or press Enter to edit groundwater flow parameters for the subcatchment
241. rmwater runoff over a study area 1 Specify a default set of options and object properties to use see Section 5 4 2 Draw a network representation of the physical components of the study area see Section 6 2 3 Edit the properties of the objects that make up the system see Section 6 4 4 Select a set of analysis options see Section 8 1 5 Run a simulation see Section 8 2 6 View the results of the simulation see Chapter 9 Alternatively a modeler may convert an input file from an older version of EPA SWMM instead of developing a new model as in Steps 1 through 4 1 6 About This Manual Chapter 2 presents a short tutorial to help get started using EPA SWMM It shows how to add objects toa SWMM project how to edit the properties of these objects how to run a single event simulation for both hydrology and water quality and how to run a long term continuous simulation Chapter 3 provides background material on how SWMM models stormwater runoff within a drainage area It discusses the behavior of the physical components that comprise a stormwater drainage area and collection system as well as how additional modeling information such as rainfall quantity dry weather sanitary inflows and operational control are handled It also provides an overview of how the numerical simulation of system hydrology hydraulics and water quality behavior is carried out Chapter 4 shows how the EPA SWMM graphical user interface is orga
242. roduces the most theoretically accurate results These equations consist of the continuity and momentum equations for conduits and a volume continuity equation at nodes With this form of routing it is possible to represent pressurized flow when a closed conduit becomes full such that flows can exceed the full normal flow value Flooding occurs when the water depth at a node exceeds the maximum available depth and the excess flow is either lost from the system or can pond atop the node and re enter the drainage system Dynamic wave routing can account for channel storage backwater entrance exit losses flow reversal and pressurized flow Because it couples together the solution for both water levels at nodes and flow in conduits it can be applied to any general network layout even those containing multiple downstream diversions and loops It is the method of choice for systems subjected to significant backwater effects due to downstream flow restrictions and with flow regulation via weirs and orifices This generality comes at a price of having to use much smaller time steps on the order of a minute or less SWMM will automatically reduce the user defined maximum time step as needed to maintain numerical stability Each of these routing methods employs the Manning equation to relate flow rate to flow depth and bed or friction slope The one exception is for circular Force Main shapes where the Hazen Williams equation is used instead 57
243. rom A and B by 3 Soils close to saturation Choose value close to min infiltration rate Soils which have partially dried out Divide values from A and B by 1 5 2 5 Min Infil Rate Minimum infiltration rate on the Horton curve in hr or mm hr Equivalent to the soil s saturated hydraulic conductivity See the Soil Characteristics Table in Section A 2 for typical values Decay Const Infiltration rate decay constant for the Horton curve 1 hours Typical values range between 2 and 7 Drying Time Time in days for a fully saturated soil to dry completely Typical values range from 2 to 14 days Max Infil Vol Maximum infiltration volume possible inches or mm O if not applicable It can be estimated as the difference between a soil s porosity and its wilting point times the depth of the infiltration zone 186 Green Ampt Infiltration Parameters The following data fields appear in the Infiltration Editor for Green Ampt infiltration Suction Head Average value of soil capillary suction along the wetting front inches or mm Conductivity Soil saturated hydraulic conductivity Gin hr or mm hr Initial Deficit Fraction of soil volume that is initially dry 1 e difference between soil porosity and initial moisture content For a completely drained soil it is the difference between the soil s porosity and its field capacity Typical values for all of these parameters can be found in the Soil Characteristics T
244. rom a different computer program The format of the file is the same as that of the routing interface file discussed below where Flow is the only variable contained in the file Routing Files A routing interface file stores a time series of flows and pollutant concentrations that are discharged from the outfall nodes of drainage system model This file can serve as the source of inflow to another drainage system model that is connected at the outfalls of the first system A Combine utility is available on the File menu that will combine pairs of routing interface files into a single interface file This allows very large systems to be broken into smaller sub systems that can be analyzed separately and linked together through the routing interface file Figure 11 1 below illustrates this concept 144 prop inp save outed dat Combine outl dat outi dat gt gt inp3 dat proj inp save outl dat projs inp use imps dat Figure 11 1 Example of using the Combine utility to merge Routing files together A single SWMM run can utilize an outflows routing file to save results generated at a system s outfalls an inflows routing file to supply hydrograph and pollutograph inflows at selected nodes or both RDII Routing File Format RDII interface files and routing interface files have the same text format dl 2 Ss 4 Ol oOo oO N O the first line contains the keyword SWMM5 without the quotes
245. rs to this average value Rainfall Dependent Infiltration Inflow RDIT These are stormwater flows that enter sanitary or combined sewers due to inflow from direct connections of downspouts sump pumps foundation drains etc as well as infiltration of subsurface water through cracked pipes leaky joints poor manhole connections etc RDII can be computed for a given rainfall record based on set of triangular unit hydrographs UH that determine a short term intermediate term and long term inflow response for each time period of rainfall Any number of UH sets can be supplied for different sewershed areas and different months of the year RDI flows can also be specified in an external RDH interface file Direct Dry Weather and RDII inflows are properties associated with each type of drainage system node junctions outfalls flow dividers and storage units and can be specified when 47 nodes are edited It is also possible to make the outflows generated from an upstream drainage system be the inflows to a downstream system by using interface files See Section 11 7 for further details 3 3 7 Control Rules Control Rules determine how pumps and regulators in the drainage system will be adjusted over the course of a simulation Some examples of these rules are Simple time based pump control RULE RI IF SIMULATION TIME gt 8 THEN PUMP 12 STATUS ON ELSE PUMP 12 STATUS OFF Multiple condition orifice gate control RUL
246. rst select the object s name with the mouse and choose Edit gt gt Find Object from the Main Menu or press the 4 button on the Standard Toolbar and select Find Object from the dropdown menu Then in the Map Finder dialog that appears select the type of object to look for Subcatchment Node or Link and press the Go button the object s name will have already been entered in the form The object will appear highlighted in both the Data Browser and on the Study Area Map 117 9 2 Variables That Can Be Viewed Computed results at each reporting time step for the following variables are available for viewing on the map and can be plotted tabulated and statistically analyzed Subcatchment Variables rainfall rate in hr or mm hr snow depth inches or millimeters losses infiltration evaporation in in hr or mm hr runoff flow flow units groundwater flow into the drainage network flow units groundwater elevation ft or m washoff concentration of each pollutant mass liter Node Variables 9 3 water depth ft or m above the node invert elevation hydraulic head ft or m absolute elevation per vertical datum water volume held in storage including ponded water ft or m lateral inflow runoff all other external inflows in flow units total inflow lateral inflow upstream inflows in flow units surface flooding flow lost from the system when the node s inflow exceeds its available sto
247. rvious area of a subcatchment The Pervious snow pack area encompasses the entire pervious area of a subcatchment 44 Each of these three areas is characterized by the following parameters Minimum and maximum snow melt coefficients minimum air temperature for snow melt to occur snow depth above which 100 areal coverage occurs initial snow depth initial and maximum free water content in the pack In addition a set of snow removal parameters can be assigned to the Plowable area These parameters consist of the depth at which snow removal begins and the fractions of snow moved onto various other areas Subcatchments are assigned a snow pack object through their Snow Pack property A single snow pack object can be applied to any number of subcatchments Assigning a snow pack to a subcatchment simply establishes the melt parameters and initial snow conditions for that subcatchment Internally SWMM creates a physical snow pack for each subcatchment which tracks snow accumulation and melting for that particular subcatchment based on its snow pack parameters its amount of pervious and impervious area and the precipitation history it sees 3 3 3 Aquifers Aquifers are sub surface groundwater areas used to model the vertical movement of water infiltrating from the subcatchments that lie above them They also permit the infiltration of groundwater into the drainage system or exfiltration of surface water from the drainage system
248. s as inputs 3 2 Visual Objects Figure 3 1 depicts how a collection of SWMM s visual objects might be arranged together to represent a stormwater drainage system These objects can be displayed on a map in the SWMM workspace The following sections describe each of these objects 33 Raingage Uy Subcatchmernt Junction Conduit Divider Outfall Requlator storage Unit Figure 3 1 Example of physical objects used to model a drainage system 3 2 1 Rain Gages Rain Gages supply precipitation data for one or more subcatchment areas in a study region The rainfall data can be either a user defined time series or come from an external file Several different popular rainfall file formats currently in use are supported as well as a standard user defined format The principal input properties of rain gages include rainfall data type e g intensity volume or cumulative volume recording time interval e g hourly 15 minute etc source of rainfall data input time series or external file name of rainfall data source 3 2 2 Subcatchments Subcatchments are hydrologic units of land whose topography and drainage system elements direct surface runoff to a single discharge point The user is responsible for dividing a study area into an appropriate number of subcatchments and for identifying the outlet point of each subcatchment Discharge outlet points can be either nodes of the drainage system or other subcatch
249. s in this box if need be 22 5 Click the OK button to create the plot showing the water surface profile as it exists at the simulation time currently selected in the Map Browser see Figure 2 15 Profile Node J1 Out P da Taa i 1 i J be i I I LLI J P Distance Tt OB 12002 02 45 00 Figure 2 15 Example of a Profile Plot As you move through time using the Map Browser or with the Animator control the water depth profile on the plot will be updated Observe how node J2 becomes flooded between hours 2 and 3 of the storm event A Profile Plot s appearance can be customized and it can be copied or printed using the same procedures as for a Time Series Plot Running a Full Dynamic Wave Analysis In the analysis just run we chose to use the Kinematic Wave method of routing flows through our drainage system This is an efficient but simplified approach that cannot deal with such phenomena as backwater effects pressurized flow flow reversal and non dendritic layouts SWMM also includes a Dynamic Wave routing procedure that can represent these conditions This procedure however requires more computation time due to the need for smaller time steps to maintain numerical stability Most of the effects mentioned above would not apply to our example However we had one conduit C2 which flowed full and caused its upstream junction to flood It could be that this pipe is actually b
250. ss Rate Bottom Elevation Conductivity Soul s saturated hydraulic conductivity in hr or mm hr Water Table Elevation Unsat one Moisture Userassigned aquifer name Conductivity Slope Average slope of log conductivity versus soil moisture deficit porosity minus moisture content curve nie Tension Slope Average slope of soil tension versus soil moisture content curve inches or mm Upper Evaporation Fraction Fraction of total evaporation available for evapotranspiration in the upper unsaturated zone Lower Evaporation Depth Maximum depth into the lower saturated zone over which evapotranspiration can occur ft or m Lower Groundwater Loss Rate Rate of percolation from saturated zone to deep groundwater in hr or mm hr 171 Bottom Elevation Elevation of the bottom of the aquifer ft or m Water Table Elevation Elevation of the water table in the aquifer at the start of the simulation ft or m Unsaturated Zone Moisture Moisture content of the unsaturated upper zone of the aquifer at the start of the simulation volumetric fraction cannot exceed soil porosity C 2 Climatology Editor The Climatology Editor is used to enter values for various climate related variables required by certain SWMM simulations The dialog is divided into five tabbed pages where each page provides a separate editor for a specific category of climate data Temperature Page Climatology Editor Temperature Evaporation Wi
251. ss for Conduit xxx Conduits cannot have zero or negative roughness values invalid number of barrels for Conduit xxx Conduits must consist of one or more barrels adverse slope for Conduit xxx Under Steady or Kinematic Wave routing all conduits must have positive slopes This can usually be corrected by reversing the inlet and outlet nodes of the conduit 1 e right click on the conduit and select Reverse from the popup menu that appears Adverse slopes are permitted under Dynamic Wave routing no cross section defined for Link xxx Cross section geometry was never defined for the specified link invalid cross section for Link xxx Either an invalid shape or invalid set of dimensions was specified for a link s cross section missing or invalid pump curve assigned to Pump xxx Either no pump curve or an invalid type of curve was specified for a pump 295 ERROR 131 ERROR 133 ERROR 134 ERROR 135 ERROR 136 ERROR 137 ERROR 138 ERROR 139 ERROR 141 ERROR 143 ERROR 145 ERROR 151 the following links form cyclic loops in the drainage system The Steady and Kinematic Wave flow routing methods cannot be applied to systems where a cyclic loop exists 1 e a directed path along a set of links that begins and ends at the same node Most often the cyclic nature of the loop can be eliminated by reversing the direction of one of its links 1 e switching the inlet and outlet nodes of the link The
252. st before the tool is porary J launched and can be displayed after the tool closes by using the Report gt gt Status command from the main SWMM menu SOUTFILE The name of a temporary file to which the tool can write simulation porary results in the same format used by SWMM 5 which can then be displayed after the tool closes in the same fashion as if a SWMM run were made SRIFFILE The name of the Runoff Interface File as specified in the Interface Files page of the Simulation Options dialog to which runoff simulation results were saved from a previous SWMM run see Sections 8 1 and 11 7 150 Disable SWMM while executing Check this option if SWMM should be minimized and disabled while the tool is executing Normally you will need to employ this option if the tool produces a modified input file or output file such as when the SINPFILE or SOUTFILE macros are used as command line parameters When this option is enabled SWMM s main window will be minimized and will not respond to user input until the tool is terminated Update SWMM after closing Check this option if SWMM should be updated after the tool finishes executing This option can only be selected if the option to disable SWMM while the tool is executing was first selected Updating can occur in two ways If the SINPFILE macro was used as a command line parameter for the tool and the corresponding temporary input file produced by SWMM was updated by the tool then the current pr
253. t Copy To Finds a specific object on the Study Area Map Edit gt gt Find Object or specific text in the Status Report Edit gt gt Find Text da boo Runs a simulation Project gt gt Run Simulation al nun Makes a visual query of the study area map View gt gt Query Creates a new profile plot of simulation results Report gt gt Graph gt gt Profile HZ 2 Creates a new time series plot of simulation results Report gt gt Graph gt gt Time Series Creates a new scatter plot of simulation results Report gt gt Graph gt gt Scatter Creates a new table of simulation results Report gt gt Table Performs a statistical analysis of simulation results Report gt gt Statistics R ME Modifies display options for the currently active view Tools gt gt Map Display Options or Report gt gt Customize ji Arranges windows in cascaded style with the study area map filling the entire display area Window gt gt Cascade Map Toolbar The Map Toolbar contains the following buttons for viewing the study area map Selects an object on the map Edit gt gt Select Object Selects link or subcatchment vertex points Edit gt gt Select Vertex Selects a region on the map Edit gt gt Select Region Pans across the map View gt gt Pan Zooms in on the map View gt gt Zoom In Zooms out on the map View gt gt Zoom Out HYP ly Draws map at full extent View gt gt
254. t value has occurred and will also estimate a return period for each event value Statistical analyses of this nature are most suitable for long term continuous simulation runs To generate a Statistics Report 1 Select Report gt gt Statistics from the Main Menu or click 2 on the Standard Toolbar 2 Fill in the Statistics Selection dialog that appears specifying the object variable and event definition to be analyzed 130 The Statistics Selection dialog is used to define the type of statistical analysis to be made on a computed simulation result It contains the following data fields Statistics Selection Object Category Subcatchment 31 3 Object N arme Variable Analyzed Rainfall Event Time Period Event Dependent Statistic Mean Event Thresholds Rainfall Event Volume Separation Time a a B Cancel Object Category Select the category of object to analyze Subcatchment Node Link or System Object Name Enter the ID name of the object to analyze Instead of typing in an ID name you can select the object on the Study Area Map or in the Data Browser and then click the button to select it into the Object Name field Variable Analyzed Enter the name of the variable to be analyzed The available choices depend on the object category selected e g rainfall losses or runoff for subcatchments depth inflow or flooding for nodes depth flow velocity or capacity for links wate
255. t at each node of the system as well as the flow rate and concentration of each pollutant in each link The hot start file saved after a run can be used to define the initial conditions for a subsequent run Hot start files can be used to avoid the initial numerical instabilities that sometimes occur under Dynamic Wave routing For this purpose they are typically generated by imposing a constant set of base flows for a natural channel network or set of dry weather sanitary flows for a sewer network over some startup period of time The resulting hot start file from this run is then used to initialize a subsequent run where the inflows of real interest are imposed It is also possible to both use and save a hot start file in a single run starting off the run with one file and saving the ending results either to the same or to another file The resulting file can then serve as the initial conditions for a subsequent run if need be This technique can be used to divide up extremely long continuous simulations into more manageable pieces RDII Files The RDI interface file is a text file that contains a time series of rainfall dependent infiltration inflow flows for a specified set of drainage system nodes This file can be generated from a previous SWMM run when Unit Hydrographs and nodal RDII inflow data have been defined for the project or it can be created outside of SWMM using some other source of RDI data e g through measurements or output f
256. t properties are expressed depends on the choice of units for flow rate Using a flow rate expressed in cubic feet gallons or acre feet implies that US units will be used for all quantities Using a flow rate expressed in liters or cubic meters means that SI metric units will be used Flow units are selected either from the project s default Node Link properties see Section 5 4 or directly from the main window s Status Bar see Section 4 4 The units used for all properties are listed in Appendix A 1 6 5 Converting an Object It is possible to convert a node or link from one type to another without having to first delete the object and add a new one in its place An example would be converting a Junction node into an Outfall node or converting an Orifice link into a Weir link To convert a node or link to another type Right click the object on the map Select Convert To from the popup menu that appears Select the new type of node or link to convert to from the sub menu that appears aA w N Pp Edit the object to provide any data that was not included with the previous type of object Only data that is common to both types of objects will be preserved after an object is converted to a different type For nodes this includes its name position description tag external inflows treatment functions and invert elevation For links it includes just its name end nodes description and tag 6 6 Copying and Pasting Objects
257. t the file and close the dialog In the Station No field of the Property Editor enter 310301 Select the Options category in the Data Browser and click the button to bring up the Simulation Options form On the General page of the form select Kinematic Wave as the Routing Method this will help speed up the computations On the Date page of the form set both the Start Analysis and Start Reporting dates to 01 01 1998 and set the End Analysis date to 01 01 2000 29 9 On the Time Steps page of the form set the Routing Time Step to 300 seconds 10 Close the Simulation Options form by clicking the OK button and start the simulation by selecting Project gt gt Run Simulation or by clicking on the Standard Toolbar After our continuous simulation is completed we can perform a statistical frequency analysis on any of the variables produced as output For example to determine the distribution of rainfall volumes within each storm event over the two year period simulated 1 Select Report gt gt Statistics or click the button on the Standard Toolbar 2 In the Statistics Selection dialog that appears enter the values shown in Figure 2 22 3 Click the OK button to close the form n 8 Statistics Selection Siti E Object Category Variable Analyzed Faintall Event Time Period EventDependent Statistic Total Event Thresholds Rainfall Event Yolume Inter E vent Hours Figure 2 22 Statistics Selection dialog
258. te of backdrop image Y1 lower left Y coordinate of backdrop image X2 upper right X coordinate of backdrop image Y2 upper right Y coordinate of backdrop image 253 This page intentionally left blank 254 APPENDIX E ERROR MESSAGES ERROR 101 ERROR 103 ERROR 105 ERROR 107 ERROR 108 ERROR 109 ERROR 111 ERROR 113 ERROR 114 ERROR 115 ERROR 117 ERROR 119 ERROR 121 memory allocation error There is not enough physical memory in the computer to analyze the study area cannot solve KW equations for Link xxx The internal solver for Kinematic Wave routing failed to converge for the specified link at some stage of the simulation cannot open ODE solver The system could not open its Ordinary Differential Equation solver cannot compute a valid time step A valid time step for runoff or flow routing calculations 1 e a number greater than 0 could not be computed at some stage of the simulation ambiguous outlet ID name for Subcatchment xxx The name of the element identified as the outlet of a subcatchment belongs to both a node and a subcatchment in the project s data base invalid parameter values for Aquifer xxx The properties entered for an aquifer object were either invalid numbers or were inconsistent with one another e g the soil field capacity was higher than the porosity invalid length for Conduit xxx Conduits cannot have zero or negative lengths invalid roughne
259. ted using the Map Browser To create a Profile Plot 1 Select Report gt gt Graph gt gt Profile from the main menu or press S on the Standard Toolbar A Profile Plot dialog will appear see below Use it to identify the path along which the profile plot is to be drawn Profile Plot E IB x Create Profile Links in Profile Start Node moo E End Mode w E Find Path Save Current Profile eje The Profile Plot dialog is used to specify a path of connected conveyance system links along which a water depth profile versus distance should be drawn To define a path using the dialog 1 Enter the ID of the upstream node of the first link in the path in the Start Node edit field or click on the node on the Study Area Map and then on the button next to the edit field Enter the ID of the downstream node of the last link in the path in the End Node edit field or click the node on the map and then click the button next to the edit field Click the Find Path button to have the program automatically identify the path with the smallest number of links between the start and end nodes These will be listed in the Links in Profile box You can insert a new link into the Links in Profile list by selecting the new link either on the Study Area Map or in the Data Browser and then clicking the button underneath the Links in Profile list box 122 5 Entries in the Links in Profile list can be deleted or
260. the dialog If the latter was set lower than 0 5 seconds then the variable time step option is ignored Time Step for Conduit Lengthening This is a time step in seconds used to artificially lengthen conduits so that they meet the Courant stability criterion under full flow conditions 1 e the travel time of a wave will not be smaller than the specified conduit lengthening time step As this value is decreased fewer conduits will require lengthening A value of 0 means that no conduits will be lengthened The ratio of the artificial length to the original length for each conduit is listed in the Flow Classification table that appears in the simulation s Status Report see Section 9 1 Minimum Surface Area This is a minimum surface area used at nodes when computing changes in water depth If O is entered then the default value of 12 566 ft2 1 167 m2 is used This is the area of a 4 ft diameter manhole The value entered should be in square feet for US units or square meters for SI units File Options The Interface Files page of the Simulation Options dialog is used to specify which interface files will be used or saved during the simulation Interface files are described in Chapter 11 The page contains a list box with three buttons underneath it The list box lists the currently selected files while the buttons are used as follows General D ates Time Steps Dynamic Wave Files Specify interface files to use or save
261. the file to open from the Open File dialog form that will appear 4 Click Open to open the selected file To open a project that was worked on recently 1 Select File gt gt Reopen from the Main Menu 2 Select a file from the list of recently used files to open 5 3 Saving a Project To save a project under its current name either select File gt gt Save from the Main Menu or click ll on the Standard Toolbar 73 To save a project using a different name 1 Select File gt gt Save As from the Main Menu 2 A standard File Save dialog form will appear from which you can select the folder and name that the project should be saved under 5 4 Setting Project Defaults Each project has a set of default values that are used unless overridden by the SWMM user These values fall into three categories Default ID labels labels used to identify nodes and links when they are first created Default subcatchment properties e g area width slope etc Default node link properties e g node invert conduit length routing method To set default values for a project 1 Select Project gt gt Defaults from the Main Menu 2 A Project Defaults dialog will appear with three pages one for each category listed above 3 Check the box in the lower left of the dialog form if you want to save your choices for use in all new future projects as well 4 Click OK to accept your choice of defaults The specific items for eac
262. the results from these files will automatically be available for viewing 11 3 Rainfall Files SWMM s rain gage objects can utilize rainfall data stored in external rainfall files The program currently recognizes the following formats for storing such data DSI 3240 and related formats which record hourly rainfall at U S National Weather Service NWS and Federal Aviation Agency stations available online from the National Climatic Data Center NCDC at www ncdc noaa gov oa ncdc html DSI 3260 and related formats which record fifteen minute rainfall at NWS stations also available online from NCDC HLY03 and HLY21 formats for hourly rainfall at Canadian stations available online from Environment Canada at www climate weatheroffice ec gc ca FIF21 format for fifteen minute rainfall at Canadian stations also available online from Environment Canada 4 standard user prepared format where each line of the file contains the station ID year month day hour minute and non zero precipitation reading all separated by one or more spaces An excerpt from a sample user prepared Rainfall file is as follows SLIAVI 2004 T2 00 00 012 STADT 2004 dz OF 00 004 STAL 2004 6 32 Le 00 007 When a rain gage is designated as receiving its rainfall data from a file the user must supply the name of the file and the name of the recording station referenced in the file For the standard user prepared format the rainfall
263. tiple times 216 Section Purpose Formats Remarks FILES Identifies optional interface files used or saved by a run USE SAVE RAINFALL Fname USE SAVE RUNOFF Fname USE SAVE HOTSTART Fname USE SAVE RDII Fname USE INE LOWS Fname SAVE OUTFLOWS Fname Fname name of interface file Refer to Section 11 7 for a description of interface files Rainfall Runoff and RDII files can either be used or saved in a run but not both A run can both use and save a Hot Start file with different names Section Purpose Formats Remarks RAINGAGES Identifies each rain gage that provides rainfall data for the study area Name Form Intvl SCF TIMESERIES Tseries Name Form Intvl SCF FILE Fname Sta Units Name Form INEVI SCF Tseries Fname Sta Units name assigned to rain gage form of recorded rainfall either INTENSITY VOLUME or CUMULATIVE time interval between gage readings in decimal hours or hours minutes format e g 0 15 for 15 minute readings snow catch deficiency correction factor use 1 0 for no adjustment name of time series in TIMESERIES section with rainfall data name of external file with rainfall data Rainfall files are discussed in Section 11 3 name of recording station used in the rain file rain depth units used in the rain file either IN inches or MM millimeters 217 Section Purpose Formats Remarks EVAPORATION Specifies how daily evapo
264. tting at Weir W25 varied with the water depth at Node N2 In rule MC3 the PID controller adjusts the opening of Orifice O12 to maintain a flow of 1 6 in Link L33 180 PID Controllers A PID Proportional Integral Derivative Controller is a generic closed loop control scheme that tries to maintain a desired set point on some process variable by computing and applying a corrective action that adjusts the process accordingly In the context of a hydraulic conveyance system a PID controller might be used to adjust the opening on a gated orifice to maintain a target flow rate in a specific conduit or to adjust a variable speed pump to maintain a desired depth in a storage unit The classical PID controller has the form 1 d MEIER y i L a where m t controller output K proportional coefficient gain T integral time Tg derivative time e t error difference between setpoint and observed variable value and t time The performance of a PID controller is determined by the values assigned to the coefficients K T and Ty The controller output m t has the same meaning as a link setting used in a rule s Action Clause while d is the current flow routing time step in minutes Because link settings are relative values with respect to either a pump s standard operating curve or to the full opening height of an orifice or weir the error e t used by the controller is also a relative value It is defined as the difference between t
265. tudy Area Map If left blank then the rain gage will not appear on the map Y Coordinate Vertical location of the rain gage on the Study Area Map If left blank then the rain gage will not appear on the map if Description Click the ellipsis button or press Enter to edit an optional description of the rain gage Tag Optional label used to categorize or classify the rain gage Rain Format Format in which the rain data are supplied INTENSITY each rainfall value is an average rate in inches hour or mm hour over the recording interval VOLUME each rainfall value is the volume of rain that fell in the recording interval in inches or millimeters CUMULATIVE each rainfall value represents the cumulative rainfall that has occurred since the start of the last series of non zero values in inches or millimeters i hours or hours minutes format Snow Catch Factor that corrects gage readings for snowfall Factor Data Source Source of rainfall data either TIMESERIES for user supplied time series data or FILE for an external data file TIME SERIES Series Name Name of time series with rainfall data if Data Source selection was TIMESERIES leave blank otherwise double click to edit the series DATA FILE File Name Name of external file containing rainfall data Station No Recording gage station number Rain Units Depth units IN or MM for rainfall values in the file Rain Interval
266. tudy area 3 3 1 Climatology Temperature Air temperature data are used when simulating snowfall and snowmelt processes during runoff calculations If these processes are not being simulated then temperature data are not required Air temperature data can be supplied to SWMM from one of the following sources auser defined time series of point values values at intermediate times are interpolated an external climate file containing daily minimum and maximum values SWMM fits a sinusoidal curve through these values depending on the day of the year For user defined time series temperatures are in degrees F for US units and degrees C for metric units The external climate file can also be used to supply evaporation and wind speed as well Evaporation Evaporation can occur for standing water on subcatchment surfaces for subsurface water in groundwater aquifers and for water held in storage units Evaporation rates can be stated as a single constant value a set of monthly average values 4 user defined time series of daily values daily values read from an external climate file If a climate file is used then a set of monthly pan coefficients should also be supplied to convert the pan evaporation data to free water surface values Wind Speed 43 Wind speed is an optional climatic variable that is only used for snowmelt calculations SWMM can use either a set of monthly average speeds or wind speed data contained
267. turated soil to completely dry 3 4 3 Groundwater Figure 3 6 is a definitional sketch of the two zone groundwater model that is used in SWMM The upper zone is unsaturated with a variable moisture content of 0 The lower zone is fully saturated and therefore its moisture content is fixed at the soil porosity 0 The fluxes shown in the figure expressed as volume per unit area per unit time consist of the following f feu Te d ae A APO poe d L TOF d f L Figure 3 6 Two zone groundwater model f infiltration from the surface fey evapotranspiration from the upper zone which is a fixed fraction of the un used surface evaporation fy percolation from the upper to lower zone which depends on the upper zone moisture content 8 and depth dy fer evapotranspiration from the lower zone which is a function of the depth of the upper zone dy f percolation from the lower zone to deep groundwater which depends on the lower zone depth dy fg lateral groundwater interflow to the drainage system which depends on the lower zone depth d as well as the depth in the receiving channel or node After computing the water fluxes that exist during a given time step a mass balance is written for the change in water volume stored in each zone so that a new water table depth and unsaturated zone moisture content can be computed for the next time step 3 4 4 Snowmelt The snowmelt routine in SWMM is a part of the runoff modeling process
268. ty of the model and to determine if the simulation results are valid for the modeling objectives Time series plots at key locations in the network can help identify such situations as can a scatter plot between a link s flow and the corresponding water depth at its upstream node see Section 9 4 Viewing Results with a Graph Numerical instabilities can occur over short durations and may not be apparent when time series are plotted with a long time interval When detecting such instabilities it is recommended that a reporting time step of 1 minute or less be used at least for an initial screening of results The run s Status Report lists the links having the five highest values of a Flow Instability Index FIT This index counts the number of times that the flow value in a link is higher or lower than the flow in both the previous and subsequent time periods The index is normalized with respect to the expected number of such turns that would occur for a purely random series of values and can range from U to 150 As an example of how the Flow Instability Index can be used consider the figure shown below The solid line plots the flow hydrograph for the link identified as having the highest FII value 100 in a dynamic wave flow routing run that used a fixed time step of 30 seconds The dashed line shows the hydrograph that results when a variable time step was used instead which is now completely stable 800 Fixed Time Step 600 F
269. tyle box ID names and parameter values can be displayed next to all subcatchments nodes and or links by selecting the appropriate options on the Annotation page of the Map Options dialog see Section 7 11 Subcatchments nodes or links meeting a specific criterion can be identified by submitting a Map Query see Section 7 8 You can animate the display of results on the network map either forward or backward in time by using the controls on the Animator panel of the Map Browser see Section 4 7 The map can be printed copied to the Windows clipboard or saved as a DXF file or Windows metafile see Section 7 12 9 4 Viewing Results with a Graph Analysis results can be viewed using several different types of graphs Graphs can be printed copied to the Windows clipboard or saved to a text file or to a Windows metafile The following types of graphs can be created from available simulation results Link 1602 Flow co a D Time Series Plot T o Flows LC FS E 2 LA E o U 1 2 3 4 5 E T D 3 Elapsed Time hours Water Elevation Profile Node 81009 16009 Profile Plot Elevation ft 10 000 5 000 0 Distance ft 01 01 2002 01 30 00 119 Link 1600 Flow v Node 16109 Depth 80 Scatter Plot int 5 60 0 E i iL 40 0 a I a I un i 20 0 a i 0 0 e 1 2 Node 16109 Depth tt You can zoom in or out of any grap
270. ubcatchments Hodes Links Subcatchments selects the theme to display for the subcatchment areas shown on the Map Nodes selects the theme to display for the drainage system nodes shown on the Map Links selects the theme to display for the drainage system links shown on the Map The Time Period panel of the Map Browser allows is used to select a time period in which to view computed results in thematic fashion on the Study Area Map Time Period Date UT 20171999 4 nm ta Time of Day 0300 00 w CS IR gt Elapsed Time 0030000 Ja Date selects the day for which simulation results will be viewed Time of Day selects the hour of the current day for which simulation results will be viewed Elapsed Time selects the elapsed time from the start of the simulation for which results will be viewed 68 The Animator panel of the Map Browser contains controls for animating the Study Area Map and all Profile Plots through time 1 e updating map color coding and hydraulic grade line profile depths as the simulation time clock is automatically moved forward or back The meaning of the control buttons are as follows Animator I4 Returns to the starting period M 4 gt 4 Starts animating backwards in time 7 Stops the animation E Starts animating forwards in time The slider bar is used to adjust the animation speed 4 8 Property Editor The Property Editor shown to the right is used to edit 7 7 gt
271. uble clicking on it To move a legend to another location press the left mouse button over the legend drag the legend to its new location with the button held down and then release the button To edit a legend either select View gt gt Legends gt gt Modify from the Main Menu or right click on the legend if it is visible Then use the Legend Editor dialog that appears to modify the legend s colors and intervals 96 Lepend Editor Flow 1 60 Color Ramp Lance Z Framed CFS Click on color you wish to change The Legend Editor is used to set numerical ranges to which different colors are assigned for viewing a particular parameter on the network map It works as follows Numerical values in increasing order are entered in the edit boxes to define the ranges Not all four boxes need to have values To change a color click on its color band in the Editor and then select a new color from the Color Dialog that will appear Click the Auto Scale button to automatically assign ranges based on the minimum and maximum values attained by the parameter in question at the current time period The Color Ramp button is used to select from a list of built in color schemes The Reverse Colors button reverses the ordering of the current set of colors the color in the lowest range becomes that of the highest range and so on Check Framed if you want a frame drawn around the legend 7 11 Using the Overview Map
272. ulated The available choices depend on the category of object selected Identify one or more objects in the category by successively clicking the object either on the Study Area Map or in the Data Browser and then clicking the button on the dialog Click the OK button to create the table 129 Table by Variable Start Date End Date 01701 1398 w 01702 1998 Ww Time Format Object Category Yarnlablez Subcatchments Rainfall Snow Depth Losses Y lw Flow Gi Elev 155 A maximum of 6 objects can be selected for a single table Objects already selected can be deleted moved up in the order or moved down in the order by clicking the i e and Ly buttons respectively 9 7 Viewing a Statistics Report A Statistics Report can be generated from the time series of simulation results For a given object and variable this report will do the following segregate the simulation period into a sequence of non overlapping events either by day month or by flow or volume above some minimum threshold value compute a statistical value that characterizes each event such as the mean maximum or total sum of the variable over the event s time period compute summary statistics for the entire set of event values mean standard deviation and skewness perform a frequency analysis on the set of event values The frequency analysis of event values will determine the frequency at which a particular even
273. ule is selected for editing The editor contains a memo field where the entire collection of control rules is displayed and can be edited Control Rule Format Each control rule is a series of statements of the form RULE rulelD IF Gong cron 1 AND Gono Teron z OR condition 3 AND Cond ve ron 4 ECO THEN action 1 AND accion ECCO ELSE action 3 AND action 4 BES PRIORITY value where keywords are shown in boldface and ruleID is an ID label assigned to the rule condition_n is a Condition Clause action_n is an Action Clause and value is a priority value e g a number from 1 to 5 The formats used for Condition and Action clauses are discussed below Only the RULE IF and THEN portions of a rule are required the ELSE and PRIORITY portions are optional Blank lines between clauses are permitted and any text to the right of a semicolon is considered a comment When mixing AND and OR clauses the OR operator has higher precedence than AND 1 e LE AL Oe B and is equivalent to IF A Or By sama Es If the interpretation was meant to be TE A Or Band C then this can be expressed using two rules as in IF A THEN IF B and C THEN The PRIORITY value is used to determine which rule applies when two or more rules require that conflicting actions be taken on a link A rule without a priority value always has a lower 178 priority than one with a value For two rules with the same priority value the rule
274. ult property value This is conduit C4 the outlet pipe whose diameter should be 1 5 instead of 1 ft To change its diameter select conduit C4 into the Property Editor and set the Max Depth value to 1 5 An alternative way to move from one object of a given type to the next in order or to the previous one in the Property Editor is to hit the Page Down or Page Up key 14 In order to provide a source of rainfall input to our project we need to set the rain gage s properties Select Gage into the Property Editor and set the following properties Rain Format INTENSITY Rain Interval 1 00 Data Source TIMESERIES Series Name TSI As mentioned earlier we want to simulate the response of our study area to a 3 inch 6 hour design storm A time series named 751 will contain the hourly rainfall intensities that make up this storm Thus we need to create a time series object and populate 1t with data To do this 1 From the Data Browser select the Time Series category of objects 2 Click the button on the Browser to bring up the Time Series Editor dialog see Figure 2 7 3 Enter TS in the Time Series Name field 4 Enter the values shown in Figure 2 7 into the Time and Value columns of the data entry grid leave the Date column blank 5 You can click the View button on the dialog to see a graph of the time series values Click the OK button to accept the new time series Time Series Editor Time Seres Name 151 Des
275. ure Page Monthly Averages Monthly Evaporation inday 173 The Evaporation page of the Climatology Editor dialog is used to supply evaporation rates in inches day or mm day for a study area There are four choices for specifying these rates Constant Use this choice if evaporation remains constant over time Enter the value in the edit box provided Time Series Select this choice if evaporation rates will be specified in a time series Enter or select the name of the time series in the dropdown combo box provided Click the Z button to bring up the Time Series editor for the selected series Note that for each date specified in the time series the evaporation rate remains constant at the value supplied for that date until the next date in the series is reached e interpolation is not used on the series From Climate File This choice indicates that evaporation rates will be read from the same climate file that was specified for temperature Enter values for monthly pan coefficients in the data grid provided Monthly Averages Use this choice to supply an average rate for each month of the year Enter the value for each month in the data grid provided Note that rates remain constant within each month Wind Speed Page Climatology Editor Temperature Evaporation Wind Speed SrowMelt Arall From Climate File see Temperature Page Monthly Averages Monthly Wind Speed mph 174 The Wi
276. urements of variables at one or more locations that can be compared with simulated values in Time Series Plots Separate files can be used for each of the following Subcatchment Runoff Subcatchment Groundwater Flow Subcatchment Groundwater Elevation Subcatchment Snow Pack Depth Subcatchment Pollutant Washoff Node Depth Node Lateral Inflow Node Flooding Node Water Quality Link Flow Calibration files are registered to a project by selecting Project gt gt Calibration Data from the main menu see Section 5 5 The format of the file is as follows 1 The name of the first object with calibration data is entered on a single line 2 Subsequent lines contain the following recorded measurements for the object measurement date month day year e g 6 21 2004 or number of whole days since the start of the simulation measurement time hours minutes on the measurement date or relative to the number of elapsed days measurement value for pollutants a value is required for each pollutant 3 Follow the same sequence for any additional objects 141 An excerpt from an example calibration file is shown below It contains flow values for two conduits 1030 and 1602 Note that a semicolon can be used to begin a comment In this example elapsed time rather than the actual measurement date was used SELOWS Lor Selected Conduits Conduit Days Time Flow 1030 O JER 30 O O30 0 O OLAS 23000 O 1 00 94 58 O bei a so
277. ures Smaller values reflect a thicker surface layer of snow 175 which results in reduced rates of heat transfer Values must be between U and 1 and the default is 0 5 Negative Melt Ratio This is the ratio of the heat transfer coefficient of a snow pack during non melt conditions to the coefficient during melt conditions It must be a number between 0 and 1 The default value is 0 6 Elevation Above MSL Enter the average elevation above mean sea level for the study area in feet or meters This value is used to provide a more accurate estimate of atmospheric pressure The default is 0 0 which results in a pressure of 29 9 inches Hg The effect of wind on snow melt rates during rainfall periods is greater at higher pressures which occur at lower elevations Latitude Enter the latitude of the study area in degrees North This number is used when computing the hours of sunrise and sunset which in turn are used to extend min max daily temperatures into continuous values The default is 50 degrees North Longitude Correction This is a correction in minutes of time between true solar time and the standard clock time It depends on a location s longitude 0 and the standard meridian of its time zone SM through the expression 4 0 SM This correction is used to adjust the hours of sunrise and sunset when extending daily min max temperatures into continuous values The default value is 0 Areal Depletion Page The Areal Depletion pa
278. us runoff runs onto pervious area or OUTLET if both areas drain to the subcatchment s outlet default OUTLET GRted Percent of runoff routed from one type of area to another default 100 220 Section Purpose Formats Remarks INFILTRATION Supplies infiltration parameters for each subcatchment Rainfall lost to infiltration only occurs over the pervious sub area of a subcatchment Subcat MaxRate MinRate Decay DryTime MaxInf Subeat SUCELON Conduct InmitDel Subcat CurveNo Conduct DryTime Subcat subcatchment name For Horton Infiltration MaxRate Maximum infiltration rate on Horton curve in hr or mm hr MinRate Minimum infiltration rate on Horton curve in hr or mm hr Decay Decay rate constant of Horton curve 1 hr DryTime Time it takes for fully saturated soil to dry days MaxInf Maximum infiltration volume possible 0 if not applicable in or mm For Green Ampt Infiltration Suction Soil capillary suction in or mm Conduct Soil saturated hydraulic conductivity in hr or mm hr InitDef Initial soil moisture deficit volume of voids total volume For Curve Number Infiltration CurveNo SCS Curve Number Conduct Soil saturated hydraulic conductivity in hr or mm hr DryTime Time it takes for fully saturated soil to dry days 221 Section Purpose Formats Remarks AQUIFERS Supplies parameters for each unconfined groundwater aquifer in the study area Aquifers cons
279. use land use name Percent percent of subcatchment area More than one pair of land use percentage values can be entered per line If more than one line is needed then the subcatchment name must still be entered first on the succeeding lines If a land use does not pertain to a subcatchment then it does not have to be entered If no land uses are associated with a subcatchment then no contaminants will appear in the runoff from the subcatchment 239 Section Purpose Format Remarks BUILDUP Specifies the rate at which pollutants build up over different land uses between rain events Landuse Pollutant FuncType Cl C2 C3 PerUnit Landuse land use name Pollutant pollutant name FuncType buildup function type POW EXP SAT C1 C2 C3 buildup function parameters see Table D 2 PerUnit AREA if buildup is per unit area CURBLENGTH if per length of curb Buildup is measured in pounds kilograms per unit of area or curb length for pollutants whose concentration units are either mg L or ug L If the concentration units are counts L then the buildup is expressed as counts per unit of area or curb length Table D 2 Available pollutant buildup functions t is antecedent dry days Function Equation sail 240 Section Purpose Format Remarks WASHOFF Specifies the rate at which pollutants are washed off from different land uses during rain events Landuse Pollutant FuncType Cl
280. vider Tag ts Tag Optional label used to categorize or classify the divider Optional label used to categorize or classify the divider Inflows Click the ellipsis button or press Enter to assign external direct dry weather or RDII inflows to the divider Treatment Click the ellipsis button or press Enter to edit a set of treatment functions for See a ee a aa entering the node Invert E El Invert elevation of the divider Invert elevation of the divider feet or meters or meters Max Depth Maximum depth of divider 1 e from ground surface to invert feet or meters See description for Junctions Initial Depth Depth of water at the divider at the start of the simulation feet or meters Surcharge Depth Additional depth of water beyond the maximum depth that is allowed before the junction floods feet or meters Ponded Area Area occupied by ponded water atop the junction after flooding occurs sq feet or sq meters See description for Junctions Diverted Link Name of link which receives the diverted flow Type Type of flow divider Choices are CUTOFF diverts all inflow above a defined cutoff value OVERFLOW diverts all inflow above the flow capacity of the non diverted link TABULAR uses a Diversion Curve to express diverted flow as a function of the total inflow WEIR uses a weir equation to compute diverted flow CUTOFF DIVIDER Cutoff Flow Cutoff flow value used for a CUTOF
281. want to review the material in Chapter 3 first 2 1 Example Study Area In this tutorial we will model the drainage system serving a 12 acre residential area The system layout is shown in Figure 2 1 and consists of subcatchment areas S7 through S3 storm sewer conduits C through C4 and conduit junctions J through J4 The system discharges to a creek at the point labeled Out We will first go through the steps of creating the objects shown in this diagram on SWMM s study area map and setting the various properties of these objects Then we will simulate the water quantity and quality response to a 3 inch 6 hour rainfall event as well as a continuous multi year rainfall record ZAS Y ss C YY La LLL co gt J2 Figure 2 1 Example study area 2 2 Project Setup Our first task is to create a new SWMM project and make sure that certain default options are selected Using these defaults will simplify the data entry tasks later on 1 Launch EPA SWMM if it is not already running and select File gt gt New from the Main Menu bar to create a new project 2 Select Project gt gt Defaults to open the Project Defaults dialog A subcatchment is an area of land containing a mix of pervious and impervious surfaces whose runoff drains to a common outlet point which could be either a node of the drainage network or another subcatchment 3 On the ID Labels page of the dialog set the ID Prefixes as shown i
282. wn edit box will appear where you can enter or select the name of a Transect object that describes the cross section s geometry Clicking the Edit button next to the edit box will bring up the Transect Editor from which you can edit the transect data 181 Cross Section Editor Shape Barrels Dimensions CIRCULAR vy i Fest Standard circular pipe C 5 Curve Editor The Curve Editor dialog is invoked whenever a new curve object is created or an existing curve object is selected for editing The editor adapts itself to the category of curve being edited Storage Tidal Diversion Pump or Rating To use the Curve Editor Pump Curve Editor Curve Name PUMP_CURVE1 Description 182 Enter values for the following data entry fields Name Name of the curve Type Pump Curves Only Choice of pump curve type as described in Section 3 2 Description Optional comment or description of what the curve represents Click the Z button to launch a multi line comment editor if more than one line is needed Data Grid The curve s X Y data Click the View button to see a graphical plot of the curve drawn in a separate window If additional rows are needed in the Data Grid simply press the Enter key when in the last row Right clicking over the Data Grid will make a popup Edit menu appear It contains commands to cut copy insert and paste selected cells in the grid as well as options to insert or delet
283. y factor set the Surface Water Flow Coefficient A2 to the same value as Al and set the Interaction Coefficient A3 to zero C 7 Infiltration Editor The Infiltration Editor dialog is used to specify values for the parameters that describe the rate at which rainfall infiltrates into the upper soil zone in a subcatchment s pervious area It 1s invoked when editing the Infiltration property of a subcatchment The infiltration parameters depend on which infiltration model was selected for the project Horton Green Ampt or Curve Number The choice of infiltration model can be made either by editing the project s Simulation Options see Section 8 1 or by changing the project s Default Properties see Section 5 4 Infiltration Editor Infiltration Method Property Max Inhil Fate 3 0 Min Inti Rate 05 Decay Constant 4 Dring Time 7 May Volume U Maxinurn rate on the Horton infiltration curve in hr or rn 185 Horton Infiltration Parameters The following data fields appear in the Infiltration Editor for Horton infiltration Max Infil Rate Maximum infiltration rate on the Horton curve in hr or mm hr Representative values are as follows 1 DRY soils with little or no vegetation Sandy soils 5 in hr Loam soils 3 in hr Clay soils 1 in hr 2 DRY soils with dense vegetation Multiply values in A by 2 3 MOIST soils Soils which have drained but not dried out 1 e field capacity Divide values f
284. y selecting another choice for the Constituent property However if the Cancel button is clicked then any changes made to all constituents will be ignored RDII Inflow Page The RDI page of the Inflows Editor dialog is used to specify RDI rainfall dependent infiltration inflow for the node in question The editor contains the following two input fields Inflows for Node 82309 Direct Dry Weather ADI Unit Hydrograph Group Sewershed Area acres NOTE Leave Unit Hydrograph Group field blank to remove any HUI inflow at this node Unit Hydrograph Group Enter or select from the dropdown list the name of the Unit Hydrograph group that applies to the node in question The unit hydrographs in the group are used in combination with the group s assigned rain gage to develop a time series of RDII inflows per unit area over the period of the simulation Leave this field blank to indicate that the node receives no RDII inflow Clicking the 2 button will launch the Unit Hydrograph Editor for the UH group specified Sewershed Area Enter the area in acres or hectares of the sewershed that contributes RDII to the node in question Note this area will typically be only a small localized portion of the subcatchment area that contributes surface runoff to the node 191 C 9 Initial Buildup Editor The Initial Buildup Editor is invoked from the Property Editor when editing the Initial Buildup property of a subcatchment It specifies
285. ys has a lower priority than one with a value For two rules with the same priority value the rule that appears first is given the higher priority Simple time based pump control RULE Rl LF SIMULATION LEME gt THEN PUMP 12 STATUS ON ELSE PUMP 12 STATUS OFF Multi condition orifice gate control RULE R2A TE NODE 29 DEPTH gt 12 AND LINK 165 FLOW gt 100 THEN ORIFICE R55 SETTING 0 5 RULE RZ LE NODE 23 DEPTH 12 AND LINK 165 FLOW gt 200 THEN ORIFICE R55 SETTING 1 0 RULE R2C IF NODE 23 DEPTH lt 12 OR LINK 165 FLOW lt 100 THEN ORIFICE Ros Sh TING 0 237 PID control rule RULE PID 1 IF NODE 23 DEPTH lt gt 12 THEN ORIFICE R55 SETTING PID 0 5 0 1 0 0 Pump station operation RULE R3A IF NODE NI DEPTH gt 5 THEN PUMP NIA STATUS ON RULE R3B IF NODE N1 DEPTH gt 7 THEN PUMP N1B STATUS ON RULE R3C IF NODE N1 DEPTH lt 3 THEN PUMP NIA STATUS OFF AND PUMP NIB STATUS OFF Section POLLUTANTS Purpose Identifies the pollutants being analyzed Format Name Units Crain Cgw Cii Kdecay Sflag CoPoll CoFract Remarks Name name assigned to pollutant Units concentration units MG L for milligrams per liter UG L for micrograms per liter or L for direct count per liter Crain concentration of pollutant in rainfall concentration units Cow concentration of pollutant in groundwater concentration units Cig concentration of pollutant in inflow i

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