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Appendix 25 - HEC-GeoHMS 1.0 Software Documentation

1. E 19131 1451 20 1331 E Hir Figure 9 2 Reach autoname result The following steps can be used to edit the names in the attribute table e Open and activate the attribute table of River shp Select Table Start Editing as shown in Properties Chart Start Editing Figure 9 3 edit reach name Select the X Edit tool Presson a name field entry and revise it e When the revision 15 done select Table gt Stop Editing as shown in Figure 9 4 The user is prompted to Save Edits Press Yes to save and NO to cancel the edit Properties Chart Stop Editing Figure 9 4 Stop and save revised reach name Basin AutoName This process names the subbasins sequence from upstream to downstream The naming convention adds W 10 20 and etc to the receiving reach name to form the subbasin name e g R20W20 The intent of this tool is to quickly name the reach and the user can edit the default names to something more descriptive 113 Chapter 9 Hydrologic Modeling System Steps e Select HMS gt Basin AutoName as shown in Reach Auto ame Basin Autol ame Figure 9 5 Basin AutoName menu item e The Basin Autoname operation creates a Name column in WaterShd shp attribute table as shown in of TT Shp face EK 1 eee gs 0099 00927 6563 818 20440000 15
2. Image Support Make Default Prapectarlmad Extension About HEL GeoHM Extension Extends ArcView and Spatial Analyst capabilities to develop hydrologic modeling inputs for HEC HMS Version 1 0 Constructed on Wed Jul 13 11 21 29 2000 e Press on the name label HEC GeoHMS to access the About information Check the box next to it to turn it on Press OK to close the dialog and watch the status bar in the lower left hand corner for the loading messages It is not necessary to load the Spatial Analyst extension because GeoHMS will automatically load it When properly installed and loaded HEC GeoHMS will create two custom views MainView and ProjView as shown below 147 Chapter 10 Example Application American River Basin 148 2 Untitled Prajvlew Views e setup the working directory with terrain and streamflow gage data Open a New MainView select the File Manage Data Sources Navigate to the CD ROM AmerRiverData Copy DEM called AmerRiver dem to your working directory Add the AmerRiver dem as a grid theme in the MainView select Theme Properties Note that there are about 10 million 2834 rows 3662 columns cells at 30 meters resolution that cover a rectangular area of 9340 sq km 3606 sq mi which encompasses this study watershed of 4817 sq km 1860 sq mi save the project as AmerRiver apr in the working directory E AmerRive
3. d Fobline 2 E ES E i ERE 382817 Pone 18 z M 18 ru 4 0 2 HN 20 20 SEXIES 6690 7 Pete i Bi s M lE TAN ME 16439 154281 Polline 0 TN TN 22i sl 2D E 210408 PolyLine i 01 20 T ME E NM 236248 236245 4 B River Slope e Select Basin Characteristics gt River Slope Select the DEM Vertical Units as meters because the terrain data has both the vertical and horizontal units in meters Press OK e 51 Endpt US and 5 columns are added to the River Shp attribute table ft af oa Shinde a n 5255000 Modes 281 S86 L Bue i E28 BDDD T7 497 7000 B da 312 6573000 1196 7000 P 20 00328 848 3000 6298000 LANCEA TAL A L MS 7717808000 11867000 oes 210408 e MES 22 23 23624 236245 1196 7000 8493000 RRRRERRRERRARRRRRARRERRRRARRRRRARRRIRRRRRRRRRRARRRRRRRRARHAERRRRARERRRARRRRRRRRRRRRRGRRRRGRRRRGRRRRRRRGRuRuucGsauuauaauauuamsauuuuuansuuuanauuuuudirenuunuuuuunuuuuuumuunumuhxuuRRERRERRRRRRRRRRRRRRRRRRARERRRARRERRARRARRRERARRRRRRRRRRRRRRSRRRERRERAERERRERRRSERRERSRRRRRRRRRRRRRRRGR 172 Chapter 10 Example Application American River Basin C Basin Centroid Select Basin Characteristics gt Basin Centroid Confirm the three inputs
4. Basin Centraid Centro Elevation Update Longest Flow Path Flow Path Figure 8 10 Basin Centroid menu item Confirm the three inputs and one output in the operation as shown in Figure 8 11 Press Basin Centroid Computation S ubBasin waters hd Shp HydroLE M fillarid b WehCentroid W shCentraid Help Cancel Figure 8 11 Basin centroid input and output files 94 Chapter 9 Stream and Watershed Characteristics Method 1 Bounding Box The Bounding Box method encompasses a subbasin with a rectangular box and approximates the centroid as the box center This method works really fast but may not be applicable with many basin shapes Select Bounding Box Method from the dropdown menu Press Centroid Computation Method Select Method far Watershed Centroid Computation Bounding Box Method Cancel Elipse Method Flow Path Method Figure 8 12 Centroid computation methods e Press OK at the confirmation as shown in Figure 8 13 22 Basin Centroid Computation Figure 8 13 Centroid confirmation The result of the operation is a point shapefile WshCentroid Shp showing the basin centroids as shown in 95 Chapter 9 Stream and Watershed Characteristics 96 2 AmerRiv1 al we heentroid S hp WaterShd Shp _ Batchpntshp e Gage shp _ Elepointshp Amerrivd shp
5. L Pobline 9 Polline 1 3i BatchPaint PalyLine E JA120 Polyline i 12 38407 5 AA h bes 2 PokLine 13 39400 s MEM 2 PobLine 14 NEN PokLine i 16 BatchPoint2 4 k Figure 9 17 HMS schematic line attribute table 121 Chapter 9 Hydrologic Modeling System HMS Legend This process implements HMS symbology to represent point and line features more descriptively as hydrologic elements such as junction subbasin source and others The user has the option to toggle between HMS Legend and Regular Legend Steps Select HMS HMS Legend The user can toggle between HMS Legend and Regular Legend by selecting HMS gt HMS Legend or Regular Legend 2 hmsconnsect Shp ANC hms point Shp Junction Subbasin Source R ery oir Diversion e Sink Shp lon gestfp Shp wshcentroid S hp aterShd Shp CJ Batchpnts hp Figure 9 18 HMS schematic with symbols Add Coordinates This step attaches geographic coordinates to hydrologic elements in the attribute tables of HMSPoint shp and HMSConnect shp The attachment of coordinates allows GIS data to be exported to a non proprietary ASCII format and still preserves the geospatial information 127 Chapter 9 Hydrologic Modeling System Steps Select HMS gt Add Co
6. An fata Figure 7 31 Batch Point 2 Specification e Accept the default name as BatchPoint2 as shown in Figure 7 32 Press OK 22 Define Batch Points Figure 7 32 Default Name for Batch Point 2 Outlet Locate Batch Point 3 and 4 Notice that Batch Point 3 and 4 violate the rule concerning the presence of the existing stream The batch point shapefile contains the essential fields that serve as instructions and information for the programs to perform batch subbasin delineation as shown in Figure 7 33 The field heading and values are discussed in Table 7 1 2 Attributes of Batchpnt silt Figure 7 33 Batch Point attribute table Chapter 7 Basin Processing Table 7 1 Batch Point Fields Descriptions and Values Field Headings Possible Values Shape standard ArcView Point requirement for noting the types point line polygon of shapefiles SnapDist The distance between the Real values in map user specified point to the units final outlet point for subbasin delineation Name The name of the outlet location can be overwritten by the user ID An identifier for tracking Integer values the number of points generated BatchDone An indicator if batch 0 indicates that processing has been batch processing performed for the points has not been performed yet 1 indicates that batch processing has been performed 1
7. Data Assembly The assembly of GIS data sets often requires conversion of file formats and coordinate systems as well as geographical referencing of non spatial data sets For vector data the industry standard shapefile format is preferred when working with ArcView Examples of vector data that require conversions are Digital Line Graphs for stream alignments and state Soil Geographic Data Base STATSGO data for the hydrologic soil types For raster data ESRI s ARC Grid format should be used Examples of raster data that require conversions are the terrain data and radar rainfall In addition to file formatting data assembly often requires a number of map related transformations to ensure that vector and raster data are in proper alignment and map distortions are minimized That is they have the same datum projection and common coordinate system These data sets can be overlaid for spatial analysis In essence a spot on the various data sets refers to the same point on the ground in all data sets Some common map related transformations are as follows e Projection Coordinate System Vertical and Horizontal Datum e Units e Resolution Accuracy Scales When data are assembled with GIS software the user should be aware of the distinctions between various spatial operations For example when the user joins various sized terrain tiles into a continuous terrain model the ArcInfo grid merge and or mosaic c
8. HM5 Basin Mode Edt Parameters Hew Basin Model Basin Model Save Basin Model Save Basin Model Rename Basin Model Delete Basin Model Basin Model Attributes Print Schematic Close Figure 9 41 HMS basin model attributes menu item Chapter 9 Hydrologic Modeling System F HHS Basin Model Attributes Help Basin Description Basin model created with HEC GeaHMS v1 0 Beta 7 Units Options Defaults Files File D Shmsproj GeoHMS_Ex1 mapfile map Browse Grid cell File D Shmsproj eoaHM5 Ex ModClark mod Browse OF Cancel T Figure 9 42 HMS basin model attributes specifications e Select the Files tab e To specify the Map File press Browse e Navigate to the D hmsproj GeoHMS and select the file as shown in Figure 9 42 e To specify the Grid cell File press Browse e Navigate to the D hmsproj GeoHMS and select the file ModClark mod as shown in Figure 9 42 e To specify the default methods select the Default tab Then select a loss rate ModClark for Transform this 1s the grid cell based unit graph baseflow and a routing method Press OK The resulting basin model with the background map is shown in Notice that subbasins R150W120 and R160W130 not connected to junctions these were the problems noted for Batch Points and 2 the previous data checking 135 Chapt
9. Make a note of the filename and its location Press The output file SkelConsChk txt contains the results of the check results The end portion of the file 1s shown below CHECKING SUMMARY 3E 3E 3E 3E 3E 3E 3E 3E 3E 3E 3E 3E 3E Unique names problems River Containment problems Center Containment problems River Connectivity problems VIP Relevance problems 180 Chapter 10 Example Application American River Basin E HMS Schematic Select HMS gt HMS Schematic e Review the input and output data sets as shown the window below 22 HMS Schema Generation Fireerbink RwerShp SubBasin WateShdShp 1 m vIPaints Pjamrsp A wW shLentroid wshcenmidShn o HMS Point HH5SPornt Connect 5 Cancel Press OK and press OK again at confirmation message box The HMS schematic with ArcView symbols 15 shown in the figure below 2 hms connect 5 hp hms point Shp d centroid alfp Shp ws hoentroid S hp lan gestfp Shp Elepointshp Hecigashp 181 Chapter 10 Example Application American River Basin F HMS Legend e Select HMS gt HMS Legend The user can toggle between HMS Legend and Regular Legend by selecting HMS gt HMS or Regular Legend 2 dl hms connect 5 PNE hms point Shp Junction Subbas in Source Reservoir Div
10. 175 Chapter 10 Example Application American River Basin 2 Proj amp mer lon gestfp Shp Elepointshp Hecdgashp Projamer shp oint Outlet Wr aterShd Shp Sm rid strink arid The longest flow path computation also stores physical parameters in 2 Attributes of WaterShd Shp Zw E 821 3000 6301000 0 084 0 089 9909991 1455 0000 a M 1133 0000 49377000 0044 0043 24127322 1556 DDDD 22355000 11882000 043 0034 4774 747 2983 0000 M 11450000 62381000 060 0066 4510580 1508 0000 mE 1550 0000 811 7000 0 033 0 021 1271 277 2854 0000 1523 1000 7 Terre rrr rere rrr retire rer rrr rere E Centroidal Flow Path e Select Basin Characteristics gt Centroidal Flow Path The program prompts the user to verify the five data inputs and one output 176 Chapter 10 Example Application American River Basin 2 Centroidal Flow Path Computation SubBasin
11. Cancel 86 Batchpnt shp Elepoint shp Amerriv1 shp Figure 39 Input point theme selection e With the field names available in the Gage shp select the gage number Gage field to be imported in for the Name field in the Batchpnt shp as shown in The Gage No field is a Suitable choice because it has unique values Press OK 2 Import Batch Points Select 4 Field as the field 7 Cancel Drainage a Figure 7 40 Field selection as name field Press Yes on Figure 7 41 to enable snapping 2 Import Batch Points 2 Snap the import paints to stream set Snaptn field Cancel Figure 7 41 Snap options The result indicates that the four gages in the Gage shp have been imported into the Batchpnt shp as shown in Figure 7 42 Press OK Chapter 7 Basin Processing 2 Import Batch Points i 4 point s transferred from Gage shp ta Batchpnt shp Figure 7 42 Import batch points confirmation The Batchpnt shp now contains 8 batch points as shown in Figure 7 43 The four recently added batch points are shown in yellow if the document is in color or white if this document 15 in black and white in Figure 7 44 2 1 Batchpntshp e i age shp _ Elepointshp _ Amerrivd shp BatchFP aint MidP aint Outlet River Shp i watershd shp Figure 43 Import b
12. Basin Centro Elevation Update Longest Flow Path Centroidal Flow Path Figure 8 3 River length menu item Press OK at the message box as shown in Figure 8 4 91 Chapter 9 Stream and Watershed Characteristics 2 River Length Computation Figure 8 4 River length confirmation The result of the river length computation is the Riv Length column added to the initial attribute table as shown in Riv Length is in the map units which are meters 1 this example Figure 8 5 Populated attribute table with river length River Slope 92 This step extracts the upstream and downstream elevation of a river reach and computes the slope The upstream and downstream elevation and slope are added as columns to the River shp attribute table with the column headings us ds Elv and Slp Endpt Steps e Select Basin Characteristics gt River Slope as shown in Figure 8 6 Basin Characteristics Hiver Length Hiver Slope Figure 8 6 River Slope menu item Chapter 9 Stream and Watershed Characteristics e Select the DEM Vertical Units as meters as shown because this terrain data has both the vertical and horizontal units 1n meters Sometimes the terrain data has the horizontal units of meters and vertical units 1n feet or decimeters Press OK 2 DEM Vertical Units Select DEM s vertical units Figure 8 7 DEM vertical units Press
13. E Snn n Figure 8 18 Watershed attribute table with one subbasin selected Select the Basin Charateristics gt Basin Centroid Select the Ellipse Method from the dropdown menu as shown inFigure 8 19 Press OK Centroid Computation Method Select Method for Watershed Centroid Computation Method Cancel Figure 8 19 Basin centroid with ellipse method selected A new centroid 1s re computed for the selected subbasin as shown in figure The ellipse method produces a centroid that is adjusted slightly compared to the bounding box method The elevation of the centroid 15 automatically updated 1 the Wshcentroid shp The Watershd shp and the attribute table are shown in Figure 8 20 and Figure 8 21 2 1 wzhcentroid S hp WaterShd Shp _ Batehpnt shp _ Sage shp _ Elepointshp a _ Amerrivd shp BatchP aint Figure 8 20 Ellipse method basin centroid result 98 Chapter 9 Stream and Watershed Characteristics Attributes of WaterShd Shp ETIN teu 10007 D 2 8886300 000 1 JAN 0 2632000000 1545 2000 0g 6283200000 1588000000 1821 1000 MNT 4331100000 1200000000 1509 5000 ME 3868300000 1152000000 1537 2000 Pogon Od 1674900000 107 0 8580 000000 14565000
14. Figure 8 24 Flow path method and output files The results are shown in Figure 8 25 A new centroid 15 re computed for the selected subbasin The elevation of centroid 15 automatically updated in the Wshcentroid shp and Watershd shp attribute tables as shown in 100 Chapter 9 Stream and Watershed Characteristics 2 lon gestfp Shp we heentroid S hp aterS hd Shp Batchpntshp Gage 5 Elepoint shp e L A X O 2 Attributes of WaterShd Shp LONGER in es 2 8898300000 5i 012532000000 15452000 e 0 18289200000 6 D 1588000000 18211000 POPIN ed 4391100000 7 DjT200000000 15035000 02 3858300000 011520 00000 1597 2000 Pekgon 5 0 04 1674800000 10 0 8580 000000_ 14565000 TN 4 1104300000 11 0 5760 000000 10321000 0 812890000000 3 D 1152000000 12232000 Polygon 2 147528000012 0 23220 00000 _ 1657 4000 og 23779100000 0 12060 00000 16054000 Figure 8 26 Centroidal elevation updated with the Flow Path method Method 4 User Specified Centroid Location When the three previous methods do not produce satisfactory estimates of the centroid this method allows to user to move the centroid to any location within the subbasin Steps e Select the subbasin as shown
15. US Elv Centroidal Length CentroidalFL HMS EnglishUnits Table Heading Feet Riv Length HMS Feet US Elv HMS Feet DS Elv HMS Square miles Area Feet Elevation HMS Feet Longest FL Feet HMS Feet DSElv HMS Feet CentroidalFL HMS HMS SI Units Table Heading Meters Riv Length HMS Meters US Elv HMS Meters DS Elv HMS Square kilometers Area HMS Meters Elevation HMS Meters Longest FL Meters HMS Meters DSElv HMS Meters CentroidalFL HMS 115 Chapter 9 Hydrologic Modeling System 116 Steps e Select HMS gt Map to HMS Units e Select English from dropdown menu as shown in Figure 9 7 Press OK 2 HHS Unit Conversion Figure 9 7 HMS unit conversion options Press OK in confirmation message box The unit conversion operation results in three added columns for the stream attribute table as shown in and six added columns for the subbasin attribute table as shown in The units of the added columns are as specified in Table 9 1 for the selected unit system 2 Attributes of Hiver 5hp Aly dangih AME ue Fae SARS ote Eie 10465 202 4566 264 163 Figure 9 8 River attribute table populated with HMS units fields Chapter 9 Hydrologic Modeling System Attributes of WaterShd 5hp Jonge AWS Cortes AW Seating AME UR Ar
16. under the Basin ID Chapter 10 Example Application American River Basin FS HHS Basin Model Import Iof gt Basin Model Praj amp mer Description Directory Praj amp mer Basin model created with HEC GeoH d shimeprojsProjAnner Drives Import Cancel Help e Press Import e Specify the background map file by selecting File gt Basin Model Attributes e To specify the Map File press on Browse button e Navigate to the D hmsproj and select the Mapfile map FW HHS Basin Model Attributes Help Basin Description Basin model created with HEC GeoHMS 1 0 Beta on Defaults Files Options File D AhmsprojsProjmer maptile map Browse Grid cell File Browse DE Cancel Py e Press OK 185 Chapter 10 Example Application American River Basin The basin model and the background map files are brought into HMS resulting in the following HMS Basin Schematic HMS Basin Model Projhmer File Edit Parameters Simulate View Map Help 7 R220w210 Outlet_Amer UserPoint3 Ed R230W220 2 1804180 EO e BI The subbasin and routing elements parameters then input HMS editors That information may be available from previous studies and or a new regional analysis calibrating the parameters to gaged storms
17. Tuesday February 15 2000 11 55 25 Cancel Creator Units meter Distance Units Projection Area Of Interest Background Color Select Color Commenta Figure 6 11 View Properties window Select Terrain Preprocessing Stream Definition e Confirm that the input of FlowAccGrid 15 FaccGrid The output of the StreamGrid is StrGrid see StrGrid is a default name that can be overwritten by the user e Press OK Chapter 6 Terrain Preprocessing 2 Stream GRID Definition FloweyccGrid Streamrid Help Figure 6 12 Stream definition operation The threshold types are Area in Distance Units squared which is in square miles or Number of Cells available under the dropdown menu as shown in Figure 6 13 e Select Area in Distance Units squared 22 Stream Threshold Definition Humber of Cells Figure 6 13 Stream threshold definition types Enter the threshold as 5 square miles as shown in Figure 6 14 Press OK The largest drainage area is 32 5345 miles squared 5 Cancel Figure 6 14 Stream threshold entry window The result of the Stream Definition operation is the StrGrid as shown in Figure 6 15 45 Chapter 6 Terrain Preprocessing 2 Main iew 4 strgrid 1 ob faccgrid fdirgrid fillarid Amer meters Fi
18. the table below i of WaterShd S fS fomes 9909 281 1465 0000 4 60 437 R140140 178 Chapter 10 Example Application American River Basin C Map to HMS Units Select HMS gt Map to HMS Units Select English from dropdown menu 2 5 Unit Conversion Press OK and press OK again to confirmation message box The results of the unit conversion are three added columns for the stream attribute table and six added columns for the subbasin attribute table The added columns contain the ending HMS 2 Attributes of River Shp 26491 T 2663 052 2066 268 quieras r a TT denen nennen nenne nennen EE IEEE dE 45361 130 2066 269 1632 8n 2 Attributes of WaterShd Shp Sees Cumuuxak We Zwar AAS Mele Aue DEER A140140 32913 023 15618 200 2694 548 4006 421 2067 253 D HMS Check Data e Select HMS HMS Check Data e Verify the input data sets below 179 Chapter 10 Example Application American River Basin 2 HMS Schema Consistency Checking RiverLink RwerShp OoOO O asin wateShdShp vIPoints Pjamersn O wW shLentraid JwshcentroidShp o e Help Cancel e Press OK 22 5 Schema Consistency Checking The skeletization check file 5 tet has been created In
19. Amercrivd hp E MidPoint Existing New Delineation Outlet Stream Stream Point River Shp Segment Segment vi WaterShd Shp SmallStrGrid 1 D ata strink grid _ facegrid New Subbasin fdirgrid Figure 7 14 New subbasin delineation result Method 3 Basin Subdivision on Tributary Similar to Method 2 the situation in Method 3 involves subbasin delineation on a tributary branch where the stream does not exist For example in the blue or dark stream does not have a tributary stream extending up to the area of interest indicated by the delineation point Clicking on the delineation point with the Point Delineation tool delineates a subbasin at the specified point not on the existing stream traces a new stream segment downstream from the specified point to the existing stream and splits the existing stream at the confluence 2 AmerRiv1 1 hp MidFoint Delineation Outlet River Shp 2 4 WisterShd Shp 4 Smalletr rid 1 D ata _ strink grid _ facegrid _ fdirgrid Figure 7 15 Subbasin delineation on a tributary 72 Chapter 7 Basin Processing Accept the default name for the outlet and press OK as shown in Figure 7 16 2 Subdivide Basin and River Mame the point LserPointd Cancel Figure 7 16 Default name for outlet The result of the operation 1s shown in A new
20. User s Manual Overview This manual provides detailed instructions for using the HEC GeoHMS ArcView extension to develop hydrologic inputs for HEC HMS Documentation conventions are used to make the manual easier to read The manual 1s organized as follows Chapter 1 introduction to HEC GeoHMS Chapter 2 instructions for installing the HEC GeoHMS and getting started Chapter 3 overview of the major steps in using HEC GeoHMS Chapter 4 data collection Chapter 5 1ssues related to data assembly especially the terrain data Chapter I Introduction Chapter 6 terrain preprocessing Chapter 7 basin processing Chapter 8 physical characteristics extracted for streams and watersheds Chapter 9 input files for HMS Chapter 10 example application of HEC GeoHMS Appendix A references Appendix B HMS background map file format Appendix C grid cell parameter file format Appendix D Standard Hydrologic Grid SHG specifications Appendix E program license agreement Documentation Conventions The following conventions are utilized throughout the manual to describe the windows and screens in the program interface Window and screen titles are shown in bold and italics Menu names menu items and button names are shown in bold Menus are separated from submenus with the right arrow gt Data to be typed into an input field ona window 15 shown in the courier font and within double quote A column he
21. W aterShd 5hp HydraD EM fillgrid fdirgrid WehCentraid wshcenrodShp Longesttp longesttp Shp z Centroidaltp L entraidalfp Help Cancel Figure 8 44 Centroidal flow path input and output files e Press OK at the confirmation message box as shown in Figure 8 45 22 Centroidal Flow Path Computation Figure 8 45 Centroidal flow path confirmation The result of the centroidal flow path operation is a line shapefile named Centroidalfp Shp and its attribute table as shown in Figure 8 46 respectively The centroidal flow length in the CentroidalFL column is also stored in the WaterShd shp attribute table as shown in 109 Chapter 9 Stream and Watershed Characteristics A Amerivil id alfp Shp lan gestfp Shp vuzhcentroid S hp W aterShd Shp CJ Batchpnt s hp age shp 4224 1 UE E na Poble i 5 1580 955 Polline i 00 6 2908483 Polline i 00 Pio 1561 249 Polline i 00 8i 85 807 Polling P 00 10 1114284 Polline C000 107240018 PolyLine g 1907 939 PolpLine 1653 381 2 Attributes of WaterShd Shp om 1487 0000 1186500 0093 0081 8449037 1971 0000 4224518 4 15452000 13318000 D0O93 0 092 BEo63818 2044000 1580 355 1 981 100 1624 6000 E 062 5830 509 2181 00001 2303483 1099000 1256 3000
22. WateShdShp 1 m Hydrab EM fillgrid fdirgrid WehCentraid wshcentoidShp ssi Longestfp longesttp Shp L entraidalfp Centroidaltp Help Cancel e Press OK The result of the centroidal flow path operation are the line shapefile named Centroidalfp Shp and its attribute table as shown in the figures below The centroidal flow length in the CentroidalFL column 15 also stored in the WaterShd shp 2 Proj amp mer al centroid alfp Shp ws hcentroid S hp e lon gestfp Shp _ Elepnointshp E Heclga shp Projamer shp MidP oint Outlet nee x 177 Chapter 10 Example Application American River Basin 2 Attributes of WaterShd 5hp T und 1198 2000 0043 80941 41774747 7 288300001 22982775 629 1000 0060 0066 14610580 15080000 7155 290 mE 811 7000 033 0021 7 6127 27 28540000 37148 968 249 3000 0 035 0 034 38839162 22350000 18743149 7 Develop HMS Inputs A Reach AutoName Select HMS gt River AutoName Press OK on the confirmation message box The Reach Autoname creates a Name column in the stream s attribute table as shown the table below 2 Attributes of Hiver 5hp Bl 1 roon 629 9000 B Basin AutoName Select HMS gt Basin AutoName The Basin Autoname creates a column in the subbasin s attribute table as shown
23. cccccecececcccceccceccccecececcescececscsesesescuceeuesecs 138 CONTROL SPECIFICATIONS TIME WINDOW cccecoccccececccccececececescececccecescecececesessscececucesuscsenceeess 144 HMS COMPONENTS FOR SIMULATION ccsccccecececcccccececceccecececcescscecsecescscececesassseeeecsesssseeecacess 144 Table of Contents List of Tables 1X Foreword The Hydrologic Engineering Center s HEC recent developments in Geographic Information System GIS tools for hydrologic and hydraulic modeling result from many years of interest geospatial data usage The earliest work was begun in the mid 1970 s when HEC developed software based on the concepts developed in the Harvard University s School of Landscape Architecture Honey Hill Project That early work culminated with the development of the Spatial Analysis Methodology HEC SAM which included a grid cell data bank and analysis software for hydrologic and flood damage calculations That early work had the same concepts as those of today but the limitations in the computer hardware GIS software and data availability made widespread engineering applications difficult The current development builds on those early experiences and takes the technology to several practical engineering products including HEC GeoHMS HEC resurrected its earlier efforts by reviewing current GIS capabilities in association with Professor David Maidment from the University of Texas HEC and Dr Ma
24. indicates that batch processing has been performed unsuccessfully SnapOn A flag that can be set to 1 enables enable snapping of the snapping as a user specified point to the default UR 0 can be entered by the user to disable snapping PntDesc A textual description for Batchpoint the user specified point PntTYPE A numerical value that 15 corresponds to corresponds to the the batch point PntDesc type 83 Chapter 7 Basin Processing e process the batch points in the Batchpnt shp select Basin Process Delineate at Batch Points as shown in Figure 7 34 Basin Cha Basin Merge Hiver Merge Hiver Split Basin at Confluences Import Batch Points Delineate at Batch Figure 7 34 Delineate at Batch Points menu item The result of the batch delineation is shown in Notice that BatchPoint 1 and 2 have been successfully delineated However BatchPoint 3 and 4 did not result in subbasin delineation because their placements do not comply with the rules 2 AmerRiv1 al Batchpntshp BatchP aint Elepoint shp Amerrivd hp BatchP aint MidP aint Outlet Rmer Shp WaterShd Shp W SmallstrGrid 4 Figure 35 Batch points delineation results The attribute table of the Batchpnt shp also shows a negative confirmation for subbasin delineation at Batch Points 3 and 4 Notice
25. tools Watershed boundary and stream line features are both defined in the same file which is in plain ASCII format Each feature type 15 contained in a separate section of the file it 15 not important which section is first in the file Each section begins with the keyword MapGeo followed by a colon and either BoundaryMap RiverMap Figure B 1 A map segment defines a list of map coordinates that are connected by a line A closed segment defines a polygon and an open segment defines a line Closed segments are used for watershed boundaries and open segments are used for stream lines Each segment begins with the keyword MapSegment followed by a colon and either Closed or Open The last coordinate in a closed segment is automatically connected to the first coordinate segment coordinates are defined with x y pairs Map features are automatically scaled in the Basin Model screen Coordinates are therefore independent of projection units and offset AII segments must be in the same coordinate system Appendix Background Map File Format MapGeo BoundaryMap MapSegment closed 582242 582220 582205 581981 5820254 582068 MapSegment 582810 582874 582950 582554 582667 582810 MapGeo MapSegment 582750 582687 582657 582613 Figure 1 lt 6 15000 875000 625000 000000 812500 291225005 21250005 597500 687500 000000 687500 125000 RiverMap 10750
26. v v v EJ i v fillgrid Press OK 2 Subdivide Basin and River the point e Verify the result shown below Hecdgashp Projamer shp Outlet River Shp CJ Sm allStr rid strink grid facegrid fdirgrid v Y WiaterShd Shp v L fillgrid e Press Yes 168 Chapter 10 Example Application American River Basin 22 Basin and River 63 Confirm the subdivided basin and as displayed Cancel The result of basin subdivision 1s shown below 2 al 5 Projamer shp MidP aint Outlet af River Shp AN yi WiaterShd Shp SmallStrGrid _ strink grid _ facegrid _ fdirgrid 4 169 Chapter 10 Example Application American River Basin C Obtain River Profile and subdivide from the grade break 170 Activate the River Shp e Select the stream segment shown in figure below with the select tool 2 _ Elepointshp Heclgashp al Projamer shp MidP nint Outlet River Shp iM wWaterShd Shp SmallStrGrid strink grid _ facegrid select Basin Processing River Profile 2 Ele Cht For Proj amp kmer Grid values along the selected line River Shp on Click on this Me grade break 5000 10000 15000 20000 25000 50000 35000 Review
27. 104300000 17 0 5760000000 10821000 0 4 3690000 000 9 0 11520 00000 1223 2000 0L 2378100 0 1206000000 16054000 k Figure 8 21 Centroidal elevation updated in watershed attribute table Method 3 Flow Path The Flow Path method draws the longest flow length for the subbasin and approximates the centroid as the midpoint on the longest flow length Steps e Activate the WaterShd Shp theme e Select the subbasin as shown in Figure 8 22 2 1 al vus 9 5 hp Ww WaterShd Shp Batchpntzhp i age shp _ Elepointshp d Am errivT zhp BatchFoint Figure 8 22 Basin centroid with flow path method e Select the Basin Characteristics gt Basin Centroid e Select the Flow Path Method from the dropdown menu as shown in Figure 8 23 Press 99 Chapter 9 Stream and Watershed Characteristics 3 Centroid Computation Method Select Method far Watershed Centroid Computation Cancel Figure 8 23 Basin centroid with flow path method selected Confirm the three inputs and one output in the operation as shown in Figure 8 24 The longest flow path stored in Longestfp shp theme is computed for the selected subbasin Press OK 2 Longest Flow Path Computation SubBasin Shp E M fillarid Fdirarid Longesttp Longesttp Help
28. 84 BATCH POINTS DELINEATION RESULTS ccsccssscossccsccosccssccesccccssccscscsccssccscscscessccsssescesscecssescessceess 84 BATCH POINT ATTRIBUTE TABLE AFTER SUBBASIN DELINEATION 85 IMPORT BATCH POINTS cccccsccssccscccsccsscesccesccscesccesscscesccesscessenscenscessenccesscesseuscessesccesseuscesccesseuscs 85 IMPORT BATCH POINTS MENU ITEM cssccsssccssccescccscccssccusccusccesscusccescceueseusccesccesseusceuscceesseusceees 85 lt INPUT POINT THEME SELECTION 86 FIELD SELECTION AS NAME FIELD ccscccsscssccscccsscusccsccesscessenccesccessenscesscesseuscesccessenscesccessenseuscs 86 SNAP OPTION 86 IMPORT BATCH POINTS CONFIRMATION cccccsscccscccsccescccscceusccusccescccusccusccesceusceuscceseceusceueseuesens 87 IMPORT BATCH POINTS RESULT 87 IMPORTED BATCH POINTS IN YELLOW OR WHITE 88 BATCH POINTS ATTRIBUTE TABLE 2 oe va dd pidas noue 88 RIVER SHAPEFILE ccccceccssccscccsccesccuccesccscesccescesceuccesseesceeccesceescesccesseesseeceesseesseccesseussesssesceuseessees 9 INITIAL ATTRIBUTE TABLE FOR THE RIVER SHAPEFILE ssccsccsccescesccsccsccsccuscescescescescesccsscescescancs 9 RIVER LENGTH MENU ITEM 91 RIVER LENGTH CONFI
29. Component Control Specifications New as shown in Figure 9 54 FW HMS Project Definition IE Lata View Tools Help Basin Model k F Meteorologic Model Control Specifications Open Description EE Applica Delete Figure 9 54 Control Specifications menu item e Enter Control Specs Feb 2000 for Control Specs and Time related specifications for Feb 2000 storm for Description as shown in Figure 9 55 Press FW HMHS New Control Specifications Control Specs Control Feb 2000 Description Time related specifications for Feb 2000 storm r Directory where contral specification will be stored d hmeprojsGeoHHS Cancel See User s Documentation Figure 9 55 New Control Specifications e Enter the Starting Date as 29Feb2000 the Starting Time as 0000 the Ending Date as O3Mar2000 and the Ending Time as 0000 The time interval is hour which matches with grid based precipitation at 1 Hour interval as shown in Figure Press OK 143 Chapter 9 Hydrologic Modeling System FW HHS Control Specifications Help Control Specs ID Control Feb 2000 Description Time related specifications For Feb 2000 storm Starting 29Feb2000 Starting Time 0000 Ending Date 03 2000 Ending Time 0000 Time Interval 1 Hour Apply Cancel Enter an ending date Figu
30. DUM DIIT 3424924 TBBILODOD 1561 249 S3952000 1516000 nnn 0096 4108 600 1873 0000 1795 807 Ze 8909000 1056 000 i 01871 2092498 18530000 1114264 1992 1000 1053 8000 i ME 0193 2020 660 14930000 40 018 1223 2000 925 9000 0147 0 196 3839483 1491 0000 1907 939 1534 5000 1411 8000 0 121 0 125 3998011 1896 0000 1653 381 Figure 8 48 Centroidal flow path results populated watershed attribute table 110 Chapter 9 Hydrologic Modeling System CHAPTER 9 Hydrologic Modeling System HEC GeoHMS develops a number of hydrologic inputs for HEC HMS background map file lumped basin schematic model file grid cell parameter file and distributed basin schematic model file The capability includes automatic naming of reaches and subbasins checking for errors in the basin and stream connectivity producing HMS schematic and generating the HMS related input files The hydrologic data is then entered through HMS menus This chapter will discuss the tools for generating HMS model files po that are available 1n the ProjView Boc NE GUI under the HMS menu Map to HMS Units 5 Check Data HMMS Schematic Contents dels mr Reach AutoName asin AutoName ap to HMS Units MS Data Check EC HMS Basin Schematic Add Coordinates Background File Lumped Basin Model Grid Cell Parameter File Distribu
31. HEC has developed a number of GIS modules for specific tasks such as processing terrain for drainage path generating grid based rainfall etc Those modules required users knowledgeable of UNIX ArcInfo hydrology and a number of miscellaneous sub programs HEC GeoHMS combines the functionality of those ArcInfo programs into a package that 1s easy to use with a specialized interface With this ArcView capability and a graphical user interface the user easily accesses customized menus tools and buttons instead of the command line interface in ArcInfo With GeoHMS users who are new to GIS have access to powerful GIS operations GeoHMS uses readily available digital geospatial information to construct hydrologic models more expediently than using manual methods Also development of basic watershed information will aid the engineers in estimating hydrologic parameters After gaining adequate experience with using GIS generated parameters users can take steps to streamline the process of hydrologic parameter estimation Acknowledgements Xll This HEC GeoHMS software implementation of GIS technology for hydrologic engineering has benefited from many years of research and program development From an institutional perspective the University of Texas at Austin has contributed important research development and demonstration of concepts Having that basis for the technology HEC and ESRI contributed extensive software development an
32. Setup an HEC HMS model with inputs from HEC GeoHMS A Directory Setup e Create the HMS project first and then copy the background map file basin model file and grid cell parameter file 1f appropriate into D hmsproj ProjAmer 1 Exploring D hmsproj Projamer Edit View Tools Help All Folders Contents of EHE hmspraj 1 n Amer Nove 3KB BASIN File 3 22 00 3 53 PM 226KB MAP File 3 22 00 3 58 mg Ex octz BM oct25 1g oct28 oT Setup Start HMS program 183 Chapter 10 Example Application American River Basin 184 Select File gt New Project Enter the Project as ProjAmer and Description as GIS Application of HEC GeoHMS to the American River Basin FW HHS New Project Mel x Project Praj amp mer Description Application of HEC GeoHMS to the American River Basin T Directory where project files will be stored d Shmsprap sPraj amp mer Browse Cancel Help Enter a description Far the new project Press OK Import the Basin Model on the HMS Project Definition window select the Component Basin Model Import FS HHS Project Definition ra Lata View Tools Hel Basin Model Open Meteorologic Model Control Specifications Delete Description E s Navigate to D hmsproj ProjAmer Select the ProjAmer
33. Standard Hydrologic Grid Specifications In the SHG 1 km grid the indices are 2186 2063 and in SHG 500 m they are 4371 4126 Eastern US The location 76 degrees 30 minutes west 42 degrees 25 minutes north near Ithaca New York projects to 1583506 m easting 2320477 m northing in the specified Albers projection In the SHG 2km system the indices of the cell containing this point are 1583509 i floor 791 8 791 232 j floor 75 floor 1160 2 1160 In the SHG 1 km grid the indices are 1583 2320 and in SHG 500 m they are 3167 4640 195 Appendix Program License Agreement APPENDIX E Program License Agreement License Text 196 Use of the program 1s governed by a license agreement The program can not be used unless the user accepts the terms of the agreement This appendix gives the full text of the program license agreement This HEC documentation and software was developed at U S Federal Government expense and 15 therefore in the public domain Components of the HEC software were developed using proprietary commercial software The commercial portions of the HEC software may be purchased from the commercial vendors Further the agreements require that users accept the provisions of the copyright restrictions of the commercial software components as noted in the following paragraphs Please read and accept the provisions by so indicating CopyrightO 1996 ArcVie
34. Steps e Place four batch points in the order shown in e Zoom in to batch points to specify the batch points on the cells Chapter 7 Basin Processing 2 Amermiwi Batchpnt shp BatchPoint Batch Point 1 Batch Point 4 Elepaint shp S _ Amerrivd shp MidP aint Outlet vi Pv 2 Batch Point 3 WiaterShd Shp 4 Smalletr rid 11 ata Figure 7 28 Subbasin delineation at batch points e Click on the grid cell to specify batch point 1 as shown in Figure Notice that batch point 1 follows the rule concerning the presence of the existing stream 2 1 _ Batchpntshp _ Elepointshp e Batch Point 1 _ Amerrivd shp MidP aint Outlet River Shp i 4 WaterShd Shp SmallStrerid Mo D ata Figure 7 29 Batch Point 1 specification Accept default name as BatchPoint1 as shown Press OK 2 Define Batch Points Add Batch Paint Cancel Figure 7 30 Default name for Batch Point 1 outlet 81 Chapter 7 Basin Processing 62 Locate Batch Point 2 as shown in Figure 7 32 with same procedure as before 2 Amernivl Batchpnt shp 5 BatchP aint _ Elepointshp _ Amerrivd shp MidP aint Outlet River Shp i WaterShd Shp Batch Point 2 SmallStr rid
35. The two possible coordinate systems are the Standard Hydrologic Grid SHG and the Hydrologic Rainfall Analysis Project HRAP The SHG 15 based on the Albers Equal Area projection which preserves area The SHG coordinate system 15 defined in More information on both coordinate systems 1s in Appendix D Chapter 5 Data Assembly Table 5 2 Standard Hydrologic Grid Definition Spheroid Clarke 1866 North American Datum 1983 NAD83 Central Meridian 96 degrees 0 minutes 0 seconds West Latitude of Origin 23 degrees 0 minutes 0 seconds North Ist Standard Parallel 29 degrees 30 minutes 0 seconds North 2nd Standard Parallel 45 degrees 30 minutes 0 seconds North False Northing 0 0 33 Chapter 6 Terrain Preprocessing CHAPTER 6 Terrain Preprocessing Refering to the overview in Chapter 3 the terrain preprocessing marks the first step to using HEC GeoHMS In this step a terrain model 1s used as an input to derive eight additional data sets that collectively describe the drainage patterns of the watershed and allows for stream and subbasin delineation The first five data sets in grid representation are the flow direction flow accumulation stream definition stream segmentation and watershed delineation The next two data sets are the vectorized representation of the watersheds and streams and they are the watershed polygons and the stream segments The last data set the aggregated watersheds 1s used primarily to
36. _ fdirgrid TNT E Figure 7 7 Click the cell to subdivide basin The user can accept the default name the new basin outlet or overwrite it in the text box as shown in Figure 7 8 e 0 this example accept the default name Press OK 2 Subdivide Basin and River Name the point Cancel Figure 7 8 Default outlet name e A few seconds later the result shown by the red outline is displayed and the user can examine it In this case accept the result by pressing Yes 22 Subdivide Basin and River G Confirm the subdivided basin and as displayed Ho Cancel Figure 7 9 Basin subdivision confirmation The result of the operation 1s shown in Figure 7 10 69 Chapter 7 Basin Processing 2 Amerrivd hp 2 MidPoint Subdivide W River Shp N W aterShd Shp SmallStr rid 11 Mo Data strink grid facegrid _ fdirgrid Figure 7 10 Basin subdivision result Method 2 Basin Subdivision without Existing Stream When an existing stream does not extend upstream far enough the user can use the same Basin Subdivide tool to delineate a new subbasin For example in the blue if document is in color or dark if document is in black and white stream does not extend up to the area of interest indicated by the box The tool delineates a subbasin at the specified point that is not on the exi
37. and physical characteristics 186 Appendix References APPENDIX A References Hydrologic Engineering Center 1994 HEC DSS User s Guide and Utility Manuals User s Manual U S Army Corps of Engineers Davis CA Hydrologic Engineering Center 1998 1 Flood Hydrograph Package User s Manual U S Army Corps of Engineers Davis CA Hydrologic Engineering Center 1999 Gagelnterp User s Manual DRAFT U S Army Corps of Engineers Davis CA Hydrologic Engineering Center 2000 Hydrologic Modeling System HEC HMS Technical Reference Manual U S Army Corps of Engineers Davis CA Hydrologic Engineering Center 2000 Hydrologic Modeling System HEC HMS User s Manual U S Army Corps of Engineers Davis CA Kull D W and A D Feldman 1998 Evolution of Clark s unit graph method to spatially distributed runoff J Hydrologic Engineering 3 1 9 19 Peters J C and D J Easton 1996 Runoff simulation using radar rainfall data J AWRA 32 4 753 760 187 Appendix Background Map File Format APPENDIX B Background Map File Format File Definition 188 Watershed boundaries and stream lines can be displayed as a background for hydrologic elements on the Basin Model screen The use of a background map 15 optional and not required for any calculations This appendix describes the background map file format The file can be produced using available geographic information system GIS
38. at confluences menu item The operation resulted in creating three subbasins as shown in One basin for each stream segments 79 Chapter 7 Basin Processing 3 vil Amerriwd s hp MidP aint Outlet River Shp 2 WaterShd Shp _ 11 No D ata strink grid _ facegrid _ fdirgrid Figure 7 27 Basin subdivided at confluence Batch Subbasin Delineation 80 Subbasin delineation may also be accomplished through batch processing this requires that a point shapefile be created which contains the desired outlet locations It 15 important to recognize that the batch subbasin delineation operates on the existing delineations by further delineating with the new outlet points in the shapefile If the user wants to abandon the existing delineation then the user can batch process the outlet locations and follow with subbasin revisions to remove existing delineations There are two ways to create a point shapefile for batch subbasin delineation Method 1 Batch Point Tool The user applies the 2 Batch Point tool to place points on the map display and a point shapefile named Batchpnt Shp is created To use this tool effectively the user should turn on the StrLnkGrid SmallStrGrid zoom in until the grid cell is visible and place the point within the grid cell Rules e The point should be located within the grid cell that has an existing stream
39. bufbay01 projdata db_stru EY Figure 4 1 Field documentation with photographs Data Visualization GIS data can be used to visualize multiple data sets For example aerial images can be overlaid with subbasin boundaries to see land use patterns and variability Data Types Descriptions and Sources The amount of GIS data available through governmental institutions and data vendor has grown greatly over the years Some of these data are available for free while others are provided for a fee provides a starting point for collecting and searching for GIS data The list provides brief descriptions of data used in hydrology and their sources Additional information on the data sets can generally be found at the respective institution s web site Although the terrain data 15 the minimum data requirement to run HEC GeoHMS the other data sets are important information for constructing the hydrologic model It 15 important to collect data for an area larger than your actual project region Finally metadata must also be collected for documentation 22 Chapter 4 Data Collection Table 4 1 Data Types Descriptions and Sources Digital Elevation Model DEM DEMs are originally generated from USGS maps and are available for resolutions ranging from meters to kilometer cell size The availability of the finer DEM data may be scarce at this time The DEM at 30 by 30 meter resolution 15 generally used for modeling the terrain
40. ek Unit syste English Unit End Junction Out 5456590 000 CarnwvasY 122400 000000 Label X 16 Label Y O End Junction UserPointz Canvasz 4 9935 000000 Canvas 125325 000000 Label 16 Label Y O Downstream End Figure 9 25 HMS lumped basin model example Grid Cell Parameter File The grid cell parameter file represents subbasins as grid cells for the distributed modeling approach It 15 produced by intersecting a grid with the subbasin A number of grid formats with various coordinate systems are available However it is recommended that the user select the Standard Hydrologic Grid SHG or the Hydrologic Rainfall Analysis Project HRAP instead of the User Defined Method With the radar rainfall reported in the HRAP grid format the use of SHG or HRAP grids can ensure greater alignment and compatibility between radar rainfall and a gridded subbasin More details on the selection of a grid format are available in the Appendix D The grid cell parameter file contains the parameters and units as shown in Table 9 2 Irrespective of the selected unit system in HMS the grid cell parameter file is always in SI units to maintain alignment and compatibility with radar rainfall HMS internally converts the results the selected unit system after computation 126 Chapter 9 Hydrologic Modeling System Table 9 2 Grid Cell Parameters Units Physic
41. process the user often has the opportunity to examine the outputs and make corrections to the data set as appropriate However if the user has performed terrain preprocessing a number of times then batch processing will allow terrain preprocessing to be performed unattended Basin Processing The emphasis of the subbasin delineation processing and manipulation capability 1s on flexibility ease of use and user interactivity As the user subdivides a basin or merges many smaller subbasins together the results of the operation are displayed immediately for users confirmation The ability to perform basin processing interactively 1s powerful because the results are presented quickly for the user to make a modeling decision instead of having to reprocess the data For example the user can obtain a stream profile and look for significant grade breaks If a basin subdivision at a grade break 15 desired the user just clicks on the profile at the grade break Other tools allow the user to delineate subbasins in a batch mode by supplying a data set of point locations of desired outlets HMS Model Support GeoHMS produces a number of hydrologic inputs that are used directly in HMS In addition the program supports the estimation of hydrologic parameters by providing tables of physical characteristics of the streams and watersheds While working with HEC GeoHMS the user can toggle HEC GeoHMS on off in order to bring in other ArcView Chap
42. stream profile The user can subdivide the basin based on the grade break shown above figure Select the point delineate tool Click on the profile approximately where the grade break as shown in profile Chapter 10 Example Application American River Basin 22 Subdivide Basin and River 2 Subdivide basin and river the selected point Cancel e Click Yes 2 Subdivide Basin and Hiver the point MEME Cancel Press OK e Review the result and press Yes 2 Subdivide Basin and River Confirm the subdivided basin and as displayed Cancel The result of the basin subdivision 18 shown below 2 _ Elepointshp 1 Frojamer shp MidP aint Outlet Rmwer Shp Wi aterShd Shp CJ Sm rid strink grid New subbasin outlet facegrid 171 Chapter 10 Example Application American River Basin 6 Extract Physical Characteristics of Streams and Subbasins The physical characteristics of the streams and subbasins are extracted and saved in attribute tables A River Length Select Basin Characteristics gt River Length Press OK at the message box e Length column is added to the River Shp attribute tables Attributes of mr wa t A Sp Im s Aien 1
43. the 1 under the BatchDone field heading as shown inFigure 84 Chapter 7 Basin Processing 2 Attributes of Batchpnt shp NET i 1 BatchPoint Figure 7 36 Batch point attribute table after subbasin delineation Method 2 Import Batch Points This method 15 useful when the user has existing point shapefiles containing points of interest stream flow gage locations and or previous hydrologic model outlet specifications The user can import the existing point shapefile to prepare a batch point shapefile As an example the streamflow gage locations in the Gage shp as shown in Figure 7 37 can be imported into Batchpnt Shp 2 1 5 e _ Batchpnt shp 5 BatchP aint _ Elepointshp _ Amerrivd shp BatchP oint aint Outlet River Shp iM 4 WiaterShd Shp gt re Figure 7 37 Import batch points Steps e Select the Basin Processing gt Import Batch Points as shown in Figure 7 38 Basin Processing Basin Merge Hiver Merge Hiver Protile Split Basin at Confluences Import Batch Paints D elineate at Batch Points Figure 38 Import batch points menu item 65 Chapter 7 Basin Processing Select the Gage shp theme as the input from the drop down menu as shown Figure 7 39 Press OK 2 Import Batch Points x Select the input point theme Gage shp
44. the terrain preprocessing 15 a series of steps to derive the drainage networks The steps consist of computing the flow direction flow accumulation stream definition watershed delineation watershed polygon processing stream processing and watershed aggregation These steps can be done step by step or in a batch manner Once these data sets are developed they are used in later steps for subbasin and stream delineation It is important to recognize that the watershed and stream delineation in the terrain preprocessing steps 1s preliminary In the next step basin processing the user has the capability to delineate and edit basins in accordance with project specifications Terrain preprocessing 15 performed in Main View document and is discussed in greater detail in Chapter 6 The MainView document is generally responsible for terrain preprocessing and spatial database setup Table 3 1 and Table 3 3 show the menus buttons and tools added by HEC GeoHMS when MainView document 15 activated 13 Chapter 3 Working with HEC GeoHMS An Overview 14 GIS 3 1 Terrain Preprocessing HMS Project Setup 2 Help T Alda 8 96840 19 BB 93 t Figure 3 2 MainView GUI with GeoHMS extensions features a m Surface Graphics Table 3 1 MainView menus Menus Descriptions Terrain Preprocessing Data Management i The T
45. with hydrologic modeling holds the promise of a cost effective alternative for studying watersheds The ability to perform spatial analysis for the development of lumped hydrologic parameters can not only save time and effort but also improve accuracy over traditional methods In addition hydrologic modeling has evolved to consider radar rainfall and advanced techniques for modeling the watershed on a grid level Rainfall and infiltration are computed cell by cell providing greater detail than traditional lumped methods These advanced modeling techniques have become feasible because the consuming data manipulations can now be generated efficiently with GIS spatial operations For example the ability to perform spatial overlays of information to compute lumped or grid based parameters 15 crucial for computing basin parameters especially grid based parameters HEC GeoHMS has been developed as a geospatial hydrology tool kit for engineers and hydrologists with limited GIS experience The program allows users to visualize spatial information document watershed characteristics perform spatial analysis delineate subbasins and streams construct inputs to hydrologic models and assist with report preparation Working with HEC GeoHMS through its interfaces menus tools buttons and context sensitive online help in a windows environment allows the user to expediently create hydrologic inputs that can be used directly with the Hydrologic Modeling Syst
46. 07 000000 25 49000 4174922 4174961 4175013 4174672 4174696 4174711 closed 4174024 4173973 4173902 4174000 41740023 4174024 4176706 4176594 4176468 4176359 500000 500000 750000 750000 250000 000000 500000 750000 750000 250000 750000 500000 000000 000000 500000 500000 Sample background map file 189 Appendix Grid Cell Parameter File Format APPENDIX C Grid Cell Parameter File Format File Definition 190 The ModClark transform method requires a grid cell file The file defines cells for each subbasin Parameters for each cell are also included in the grid cell file This appendix describes the grid cell file format The file can be produced using available geographic information system GIS tools The grid cell file begins with the keyword Parameter Order followed by a colon and parameter keywords indicating the order for reading parameters from the file Figure C 1 The keyword End must be on a line by itself after the Parameter Order line Valid parameter keywords are shown in Table C 1 Parameter keywords are not case sensitive and are separated by spaces If the parameter order is not defined it is assumed to be Xcoord Y coord TravelLength Area The coordinate system of Xcoord and Y coord used in the file must match the coordinate system used in the gridded DSS precipitation records Typically the coo
47. 1 Chapter 6 Terrain Preprocessing 52 To preserve the content of Viewl create another view called MainView2 Select MainView on the project window and press New Add the Amer meters DEM Perform Fill Sinks and name the filled DEM as 2 Select the Terrain Preprocessing gt Full Preprocessing Setup The default names are shown in Figure 6 26 These default names need to be changed to avoid naming conflicts with the MainViewl 2 Full Preprocessing FlawiDirGrid FlowAccGrid laecgid SS rid LinkGrid sinkgid 7 Watershed wshedshpShp Hiver Rwershp Aggregedvw atershed wshedmg shp Help Cancel Figure 6 26 Full preprocessing setup with default theme names From HydroDEM dropdown menu select the Fillgrid2 Rename the default names by adding a 2 behind the default names as shown in Figure 6 27 Press OK Chapter 6 Terrain Preprocessing Full Preprocessing HudroD EM Fillgrid FlowDirGrid FlowAceGrid 5 7 LinkGrid W aterlsrid wshB d2 Watershed wehShpe 7 Hiver 5052 Aggregedw atershed 7 Figure 6 27 Full preprocessing setup with revised theme names e Enter the threshold to initiate a stream in terms of a percentage of the largest drainage area In batch processing t
48. 130 131 DLG 23 DOQQ 24 E Eight point pour 41 Ellipse Method 97 98 173 F Fill Sinks v 40 41 52 149 Find Area 15 18 55 Index Flow Accumulation 42 43 151 Flow Direction v 41 42 150 Flow Path vii 89 90 99 101 105 107 108 175 176 Flow Trace 15 18 57 Full Processing Setup 51 G Grid Cell Parameter File 111 126 134 190 H Help 15 HMS basin model viii 20 133 134 135 136 138 HMS Model Files 12 HMS Project Setup 14 36 59 60 161 162 HUC 23 30 Hydrologic Modeling System 1 111 131 146 183 187 Hydrologic Parameters 12 20 Hydrologic Unit Code 23 24 30 Hydrologically corrected 4 29 30 31 39 41 I Identify Area 15 18 38 55 166 L Land Use Land Cover 25 Legend 111 122 182 Longest Flow Path 89 90 105 175 LULC 25 Lumped Basin Model 111 125 183 M Map Units 44 153 Meteorologic Component 20 ModClark 2 125 130 135 138 190 192 N National Hydrography Data set 24 NHD 24 Point Delineate 15 57 Profile vi 18 65 75 76 90 170 Profile Subdivide 18 76 199 Index R Reach AutoName 111 112 178 RF1 24 30 24 River Length 89 90 91 172 River Merge 65 74 River Profile 65 75 170 River Reach File 24 River Slope vi 89 92 172 S Soil Surveys Geographic Data Base 25 Specify Project Point 15 Split Basins at Confluences 65 78 SSURGO 25 Standard Hydrologi
49. 1657 4000 14512000 0083 nra 618082 21300000 12060 00000 15343000 14118000 EES 0125 3898011 1896 0000 4 Figure 8 41 Longest flow path results populated in watershed attribute table 1487 0000 1186 5000 Centroidal Flow Path 8449 037 1971 0000 This operation computes the centroidal flow path length by projecting the centroid onto the longest flow path The centroidal flow path 1s measured from the shown in Figure 8 42 o oint on the longest flow path to the subbasin outlet as 107 Chapter 9 Stream and Watershed Characteristics Loneest Flow Path 2 ce alfp Shp lan gestfp Shp wzhcecentraid Shp W aterShd Shp Batchpnt shp Projected Point L L amp Centroidal Flow Path Figure 8 42 Centroidal flow path Steps e Select Basin Characteristics gt Centroidal Flow Path as shown in Basin Characteristics Hiver Length Hiver Slope Basin Centroid Centroid Elevation Update Longest Flow Path Centroidal Flow Path Figure 8 43 Centroidal flow path menu item e The program prompts the user to verify the five data inputs and one output see Figure 8 44 Press OK 108 Chapter 9 Stream and Watershed Characteristics 22 Flow Path Computation SUBB asin
50. 24089 1770 511 EN 1770511 2116 933 2116535 2463 356 2553356 2809 778 EN 22902778 3156 2 Ho D ata B Flow Direction e Select Terrain Preprocessing Flow Direction Confirm that the input of the HydroDEM is Fillgrid The output of the FlowDirGrid is FdirGrid FdirGrid is a default name that can be overwritten by the user Press OK This step takes about 2 minutes 150 Chapter 10 Example Application American River Basin 2 MainView fdirarid fillgrid _ Amerriver dem C Flow Accumulation e Select Terrain Preprocessing gt Flow Accumulation e Confirm that the input of the FlowDirGrid is FdirGrid The output of the FlowAccGrid is FaccGrid FaccGrid is a default name that can be overwritten by the user Press OK This step takes about 21 minutes 151 Chapter 10 Example Application American River Basin al facegrid 9 0 596767 1596768 1193535 1183536 1790302 1790203 2387070 2387071 2983837 2983838 3580805 m 3580806 4177372 EE 4177373 4774140 EE 477 4141 5370908 D ata _ fdirgrid fillgrid _ Amerriver dem The above screen does not appear complete but it is Zoom in to a part of the basin to display the details of the grid cells that make up the flow accumulation grid as shown below 152 Chapter 10 Example Application American River Basi
51. 289200 000 15660 00000 1821 1000 AA A E T E E E NE T AAT E T c c ra c c c c move E d i P n lai im imei cnp elm 3856300 000 J 152000000 1597 2000 J0d0 818000000000 00 OC OC d OO O COO COO NOOSE cad aO DOC GONDOLA HORE 1674900000 10 6560 000000 1456 5000 H PPP P Pn 1104300 000 5760 000000 1092 1000 TP c Ie 14752800 00 12 33550 00000 1657 4000 c Polygon X Figure 8 29 Watershed attribute table with the selected subbasin e Activate WshCentroid Shp theme e Select Theme gt Starting Editing from the standard ArcView GUI as shown in Figure 8 30 Properties Start Editing Figure 8 30 Start Editing menu item e When the WshCentroid Shp is under editing mode a dashed box is visible around the check box as shown in Figure 8 3 1 e
52. 6 500 e 1 2 5 885 000 77123240000 1092 100 IMMO ar L8 93525 DD 123090000 1223200 L8 025000 128825 0003857400 lS 48558909 12277 36 1534900 4 Figure 9 20 Point attribute table populated with coordinates 123 Chapter 9 Hydrologic Modeling System Attributes of hmsconnect 5 hp eed Anos Cora 49903622 125433622 51285 000 123135000 c 45095 000 126105 000 49935 000 125325000 L Figure 9 21 Line attribute table populated with coordinates Background Map File 124 The background map file captures the geographic information of the subbasin boundaries and stream alignments in an ASCII text file that can be read by HMS The format specifications of the background map file are given in Appendix B Steps Select HMS gt Background Map File e Makea note of the filename and its location as shown in Figure 9 22 Press OK 2 HMS File creation The map has been created in amp e geohms ex 1 Figure 9 22 Back
53. 60 355 R70W50 m 0034 0 067 5890 508 2181 0000 2909 483 RB0W60 7 72 34343947 1661 0000 1561 249 R110W70 7 m oos 0096 T7 410880077 1873 0000 1765 807 707 207 oisi 2792 498 15630000 1114264 R130W100 7777 189 2020 660 1493 0000 740 018 R120W110 7727 Dia 3838483 1491 0000 71907338 RA0w30 7 7 2027277 oosa 0 078 618082 2130 0000 73352203 R150W120 7 2777 0 121 0125 3998 017 18960000 1653381 16044130 Figure 9 6 Subbasin autoname result Map to HMS Units 114 This step converts the physical characteristics of the reaches and subbasins from the map units to the HMS units The map unit 1s the unit of the Arc View data the terrain data is typically in meters The user has the option to convert the map units to the English or the International System SI units supported by HMS HEC HMS only uses the subbasin area at this time the other characteristics can be used for regional parameter estimation The Table 9 1 shows the HMS units the English and International System Stream River Shp Watershed WaterShd shp Chapter 9 Hydrologic Modeling System Table 9 1 HMS Unit Systems Physical Characteristics Table Heading Length Riv Length Upstream elevation US Elv Downstream elevation DS Elv Area Area Centroid Elevation Elevation Longest Flow Length LongestFP Upstream elevation US Elv Downstream elevation
54. BatchF oint Figure 8 14 Basin centroid results The basin centroid elevation is computed and stored in the attribute table as shown in Figure 8 15 In addition the basin centroid elevation is also stored in the WaterShd shp attribute table as shown in Figure 8 16 2 Attributes of wshcentroid E Figure 8 15 Basin centroid attribute table Chapter 9 Stream and Watershed Characteristics 2 Attributes of WaterShd Shp E MENT Dc NN 2 2 DIPMODYXN 1511000 E ecd 8898500 000 0 2532000000 1545 2000 Polygon 5 RR 0 B29920000 EI Pelgon a 01 4391100 000 0 12000 00000 15035000 2 J098J00000 7 Felgon i01 4 15743000007 5 0 5580 000000 1436 5000 Felgon i01 PE 3 11043000007 0 5760 000000 10321000 Felgon i1 4 3630000 000 0 11520 00000 _ 123 200 2 1479280000 M ME 0 23220 00000 _ 1553 000 i Dose Figure 8 16 Watershed attribute table with centroidal elevation Method 2 Ellipse Method The Ellipse method encompasses a subbasin with an ellipse and approximates the centroid as the ellipse center This method 1s slower than the bounding box but it generally produces more des
55. J _ SmallStrGrid _ strink grid facegrid Figure 6 36 Generation of a separate project B from Figure 6 35 63 Chapter 7 Basin Processing CHAPTER 7 Basin Processing After the terrain preprocessing 15 performed in the Main View the extracted data for the HMS model 15 generated and placed in the ProjView which allows the user to revise the subbasins delineation Subbasin and routing reach delineations include points where information is needed 1 streamflow gage locations flood damage centers environmental concerns and hydrologic and hydraulic controls The tools described in this chapter will allow the user to interactively combine or subdivide subbasins as well as to delineate subbasins to a set of points in a batch manner This chapter will discuss the tools for subbasin Basin Processing Basin Merge delineation that are Hiver Merge available in the ProjView River Profile GUI under the Basin Split Basin at Confluences Processing menu Import Batch Points Deline ate at Batch Points Contents Basin Merge Basin Subdivision River Merge River Profile olit Basins at Confluences atch Subbasin Delineation 65 Chapter 7 Basin Processing Basin Merge 66 Under the Basin Processing menu the Basin Merge menu item merges multiple subbasins according to the following rules This tool works interactively by presenting the result of the ope
56. N OPERATION RESULT 55 aero etu reader Eun ee npe 42 FLOW ACCUMULATION OPERATION 43 FLOW ACCUMULATION OPERATION RESULT ee ese ee enses essen sese 43 z VIEW PROPERTIES WINDOW eT a SEE 44 STREAM DEFINITION OPERATION eee een ee ese eei ee ese eee ee sese eee eese tesis entren 45 STREAM THRESHOLD DEFINITION TYPES ccsccsccescceccsccscceccesceccescescescesscsscescescescessesccsscsceseeecens 45 STREAM THRESHOLD ENTRY WINDOW ccscccsscccscccssccesccessceesccesccecceusscesccesceesceuscseesseusceusceeeesens 45 STREAM DEFINITION OPERATION RESULT cscccsccssscsscesccscenscesscessenccesseussenccesseessesscesseessesccesseuscs 46 2 STREAM SEGMENTATION Mora vea os dtt pc RERO 46 STREAM SEGMENTATION OPERATION RESULT cceeeene enne eene nennen hee rere reete tee see sre retener eene 47 WATERSHED DELINEATION OPERATION scccsccssccssccecccsccsccuccesccsceuccesccssesccusceescesscuscescesceusceuscs 47 59 SPECIFY OUTLET LOCATION RE S 60 GENERATE PROJECT WITH OPTIONS c ccsccssccssccsscesccsccscc
57. OK at the confirmation as shown in 2 Hiver Slope Computation Figure 8 8 River slope confirmation The river slope computation results in adding the upstream and downstream elevations and slope to the existing attribute table as shown in Bx bro po sr 13818000 1177 8000 1052 6000 1411 8000 1177 6000 2546 16408000 1624 6000 1127 8000 1052 6000 1257 0000 12559000 105 6000 IDEE 1624 6000 1469 4000 1516 5000 1516 5000 Figure 8 9 Populated attribute table with river slope 93 Chapter 9 Stream and Watershed Characteristics Basin Centroid The basin centroid location 15 estimated 1n four ways The engineering approach to locating the centroid with momentum calculations around the X and Y axis 1s not implemented here because the centroid may be outside of U shaped and other odd shaped subbasins The four methods of estimating the centroid are the bounding box ellipse flow path and user specified The basin centroid menu item can operate on all of the subbasins or on selected subbasin Steps Select Basin Charateristics gt Basin Centroid as shown in Figure 8 10 Basin Characteristics Hiver Length Hiver Slope
58. PU speed memory and hard drive space are always better Recommended Hardware Specifications The recommended hardware specifications are as follows CPU Pentium II 300Mhz Memory 256 MB Chapter 2 HEC GeoHMS Installation Hard Drive Space hard drive space availability should be at least 20 times the size of the terrain data For example if the terrain data takes up about 50 MB then the available hard drive space should be about 1 GB In many cases having ample hard drive space available will improve performance because the spatial operations often generate many temporary intermediate files and repeatedly perform files caching Required Software Specifications The required hardware specifications are as follows Operating System Windows 95 98 NT 2000 Pre installed software ArcView GIS 3 1 or later Spatial Analyst 1 1 extension or later Installation of HEC GeoHMS The installation of HEC GeoHMS will copy program files and sample data sets to the location of ArcView and Spatial Analyst HEC GeoHMS can be installed with the following methods Automatic or Manual Installation Automatic Installation e Place the CD in the CD ROM drive e Ifthe setup program does not start then select Start Settings gt Control Panel Open the Add Hardware Software icon e Follow the steps displayed in the message box to complete the installation Manual Installation The manual installation of HEC GeoHMS consists of copying GeoHMS f
59. Processing Chapter 7 to Basin Characteristics Chapter 8 to Menus HMS Chapter 9 menus Edt Theme Analysis Surface FAG windo J GR Te mj Figure 3 3 ProjView GUI with GeoHMS extensions features Chapter 3 Working with HEC GeoHMS An Overview Table 3 4 ProjView Menus Menus Descriptions Basin Processing Basin Merge Hiver Merge Hiver Profile Split Basin at Confluences Import Batch Paints Delineate at Batch Points Basin Characteristics Hiver Length Hiver Slope Basin Lentroid Centro Elevation Update Longest Flow Path Centroidal Flow Path Reach AutaM ame Basin Auto ame ta Units 5 Check Data HMS Schematic HMS Legend 4dd Coordinates Background File Lumped Basin Model Grid Cell Parameter File Distributed Basin Model Utility Display Theme Tags Set view Theme Tag Remove a Theme Tag Kep View to Image Shaded to Image This menu provides the user with interactive and batch processing capabilities to modify existing subbasins and delineate new subbasins There are also several tools available for subdividing basins and preparing batch points for delineation Chapter 7 After the user finalizes the basin delineation this menu develops the physical characteristics for both the streams and subbasins based on the terrain model The stream characteristics will be stored in t
60. RMATION 92 POPULATED ATTRIBUTE TABLE WITH RIVER LENGTH 92 BASIN CENTROID INPUT AND OUTPUT FILES cccccceccscccsccsccsccesccuscesccesccsceuccesceescesscessescesceusceuscs 94 CENTROID COMPUTATION METHODS 95 CENIBOID CONFIRMATION ona 95 BASIN RESULTS 96 CENTROID ATTRIBUTE TABLE 96 Table of Contents WATERSHED ATTRIBUTE TABLE WITH CENTROIDAL ELEVATION ecce em en mener 97 BASIN CENTROID WITH ELLIPSE METHOD 0 cccscccseccescccssccesccesccccccusccuscceeceusceuseceeeceusceuseeeaesens 97 WATERSHED ATTRIBUTE TABLE WITH ONE SUBBASIN SELECTED 98 BASIN CENTROID WITH ELLIPSE METHOD SELECTED 2 98 ELLIPSE METHOD BASIN CENTROID RESULT esi ie ese ee ees eese ene 98 IGURE 8 41 IGURE 8 42 IGURE 8 43 IGURE 8 45 IGURE 8 47 IGURE 8 48 STOP AND SAVE REVISED REACH NAME ccscccscccsscscesccesccuscesccesccescenccesccussesccenscussecsesscesseusc
61. S An Overview the project specifications should be thoroughly reviewed for any recommendations When the project does not specify a particular data set review the project s goals and objectives to help define acceptable data in terms of data storage resolution and accuracy In addition economic factors should be considered to determine the cost effectiveness in collecting and assembling the data or purchasing the data from a vendor Whether the data are collected or purchased the metadata must also be acquired to provide necessary documentation for the data Data collection 15 discussed in greater detail in Chapter 4 Data Assembly The data assembly often requires efforts of an experienced GIS user Because GIS data have many forms and formats users often need to convert the data into a common format and then into a common coordinate system For example data describing the terrain should be in ESRI s ARC Grid format and vector data such as stream alignments and streamflow gage locations should be in the shapefile format By having a common coordinate system these data sets can be overlaid and spatial operations can be performed on them Often times these data sets are provided in rectangular portions When assembling data especially the terrain special efforts are required to ensure that data are continuous along the edges Terrain data assembly 15 discussed in Chapter 5 Terrain Preprocessing Using the terrain data as input
62. S BACKGROUND MAP FILE EXAMPLE vll Table of Contents viil LUMPED BASIN MODEL FILE LOCATION ccccscceeccssccsccscccsccuscesccesccscesceesseuscenccesseuscenccesseusceeeees 125 HMS LUMPED BASIN MODEL EXAMPLE ccccesccssccssccsccesccscesccesscscesccesscussenccesseussenccesseussensees 126 MCI 127 DEFAULT ALBERS PROM CTION 128 HMS BASIN MODEL IMPORT WINDOW cseccsscceccesccsccnccesccescesccesscescesccesseuscenccesseessenccesseussensees 133 CRITICAL ERROR ON BATCH POINT 2 133 IGURE 9 40 IGURE 9 4 IGURE 9 42 HMS BASIN MODEL SCHEMATIC 136 IGURE 9 44 IGURE 9 45 IGURE 9 46 IGURE 9 47 IGURE 9 48 CRITICAL BBROR ON BATCH POINT TI Rx SEPA 134 HMS BASIN MODEL ATTRIBUTES MENU ITEM 134 HMS BASIN MODEL ATTRIBUTES SPECIFICATIONS 135 REVISION TO BASIN CONNECTIVITY WITH JUNCTION 1 cccccececececcccececececcscecececesecescececesuseecs 137 REVISION TO BASIN CONNECTIVITY WITH JUNCTION 2 cccccccccecececcccccecececcccececcescscececsesceueeecs 137 HMS BASIN MODEL WITH CORRECT CONNECTIVITY
63. S Basin file creation amp geohms exl amerriv o The Basin hmetile basin has been created in Figure 9 34 Distributed Basin Model File Location The resulting distributed basin model file in format looks similar to Figure 9 35 Basin AmerRivi Description Basin model created with HEC GeoHMS v1 0 Beta Last Modified date 2 February 2000 Last Modified Time 1 22 52 Unit System English Unit End many lines omitted gt Gridded Subbasin ReOWeo Canvass 49903 62 2000 1254314 2 2 0 Area 7 2 5 f000 Label 16 Label Y O Downstream JE1z End many lines omitted Figure 9 35 HMS distributed basin model file example Hydrologic Modeling System Connection The purpose of this section 15 to illustrate the procedure for interfacing the inputs developed in HEC GeoHMS within HEC HMS models HEC GeoHMS develops many components of an HMS model GeoHMS capabilities extend from processing the terrain model to performing spatially intensive analysis for development of grid based parameters The results produced can be controlled somewhat by focusing on the spatial description of the landscape characteristics and stream networks However from a modeling standpoint greater control over the model is often necessary to address difficult situations HMS 15 powerful in that it offers full control over the model to address hydrologic connectivity methodo
64. S PROVIDED ON AS AS IS BASIS AND WITHOUT WARRANTY HEC DISCLAIMS ALL WARRANTIES INCLUDING WITHOUT LIMITATION IMPLIED WARRANTIES OR MERCHANTABILITY OF FITNESS FOR A PARTICULART PURPOSE AND OF FREEDOM FROM INFRINGEMENT OR RIGHTS OF OTHERS HEC shall not be liable to any user for any damage or loss including without limitation any indirect consequential special or exemplary damage or loss whether or not advised of the possibility of such damage or loss Upon request of HEC the user will execute a written license agreement on the same terms and conditions here set forth 197 Appendix Program License Agreement 198 This License Agreement constitutes the entire agreement between HEC and user relating to the Software superseding all other agreements or representations and 15 offered by HEC for acceptance only without modification 1n any respect and will be deemed terminated without further notice upon any breach of its terms and conditions by user U S Government Use Where the Products are being delivered to the U S Government under a U S Government contract or subcontract use reproduction and disclosure of the Products by the U S Government shall 1n the first instance be subject to this Agreement To the extent that the U S Government is not bound by the terms and conditions of this Agreement its use reproduction and disclosure of the Products shall be subject to the restrictions set forth in I FAR 52 227 14 Alt
65. The corrected basin model 15 shown in Select the Parameters menu to enter additional hydrologic parameters per menu items Save and close the HMS Basin Model AmerRiv1 window 137 Chapter 9 Hydrologic Modeling System Basin Model AmerRiv1 Edt Parameters Simulate Help 27 1501 20 Hz Hw P h unction UserPo ha OO intz UserPoint4 20 J 1840 UA IR 120 far H wa User Ponta ais Fi i L R160 KA Junctian z H IM click and drag ta zoom in Bbl elick to reset B 1 Figure 9 46 HMS basin model with correct connectivity Meteorologic Model A number of methods are available to model the precipitation The following steps illustrate the grid based precipitation method that 15 often used in conjunction with the grid cell parameter file The gridded precipitation must be used with ModClark transform method The grid based precipitation for this example has been developed in SHG at 2000 meter resolution The rainfall is stored as a series of grids at 1 hour intervals in the Data Storage System HEC DSS HEC 1994 and 2000 The rainfall may be directly from the National Weather Service NWS NexRad if the Hydrologic Rainfall Analysis Project cell format is used modified to the HEC Standard Hydrologic Grid SHG format or interpreted from point gages with
66. US Army Corps of Engineers Hydrologic Engineering Center Geospatial Hydrologic Modeling Extension HEC GeoHMS User s Manual Version 1 0 July 2000 Approved for Public Release Distribution Unlimited CPD 77 REPORT DOCUMENTATION PAGE Form Approved OMB No 0704 0188 Public reporting burden for this collection of information is estimated to average 1 hour per response including the time for reviewing instructions searching existing data sources gathering and maintaining the data needed and completing and reviewing the collection of information Send comments regarding this burden estimate or any other aspect of this collection of information including suggestions for reducing this burden to Washington Headquarters Services Directorate for Information Operations and Reports 1215 Jefferson Davis Highway Suite 1204 Arlington VA 22202 4302 and to the Office of Management and Budget Paperwork Reduction Project 0704 0188 Washington DC 20503 1 AGENCY USE ONLY Leave Blank 2 REPORT DATE 3 REPORT TYPE AND DATES COVERED July 2000 Computer Software User s Manual 4 TITLE AND SUBTITLE 5 FUNDING NUMBERS Geospatial Hydrologic Modeling Extension HEC GeoHMS U S Army Corps of Engineers Civil User s Manual Works R amp D Work Units 32975 and 33175 6 AUTHOR S James Doan 7 PERFORMING ORGANIZATION NAME S AND ADDRESS ES 8 PERFORMING ORGANIZATION U S Army Corps of Engineers REPORT NUMBER H
67. Use the pointer tool and click on the existing centroid e The pointer turns into a double arrow Click and drag the centroid to another location as shown in Figure 8 3 1 2 AmerRiv 41 lan gestfp Shp Dashed Box wshcentroid Shp WaterShd Shp _ Batchpntshp _ Gage shp e _ Elepointshp x Figure 8 31 User Specified new basin centroid location e To stop editing and save the changes select Theme gt Stop Editing as shown in Figure 8 32 103 Chapter 9 Stream and Watershed Characteristics Properties Stop Editing Figure 8 32 Stop Editing menu After a centroid 1s moved the centroid elevation in WshCentroid Shp and WaterShd shp must be updated as shown in Figure 8 33 e Select Basin Characteristics gt Centroid Elevation Update Bazin Characteristics Hiver Length Hiver Slope Basin Centroid Centroid Elevation Update Figure 8 33 Centroid elevation update menu item The result of the user specified centroid is shown in Figure 8 34 and elevation updates to the attribute tables of the WshCentroid Shp and WaterShd shp are shown in Figure 8 35 and Figure 8 36 langesttp Shp wzhcentroid S hp WaterShd Shp _ Batchpntshp _ 5 _ Elepointshp Figure 8 34 Moved basin centroid result 104 Chapter 9 Stream and Watershed Characteris
68. ading tab name field title and name of tables files or themes name are shown in double quotes Names of tables files or themes are not case sensitive but certain letters are capitalized for readability Chapter 2 HEC GeoHMS Installation CHAPTER 2 HEC GeoHMS Installation This chapter discusses the hardware and software requirements and installation procedures for HEC GeoHMS Prior to installing this software ArcView GIS and the Spatial Analyst extension should be installed using their installation guides The following installation procedures apply to computers running the Windows 95 98 and NT 2000 operating systems After HEC GeoHMS is installed guidelines will be provided to load it within Arc View Contents e Hardware and Software Requirements e Installation of HEC GeoHMS e Loading HEC GeoHMS Hardware and Software Requirements The minimum hardware and software requirement for using HEC GeoHMS are similar to those of ArcView GIS However when working with GIS it 15 important to take into account the size of the data sets as well as the complexity of the analysis when determining adequate computer resources Even though the program will still work on a slower machine the user will often experience long computing times To assure that performance is not being compromised the following hardware recommendations should be considered with the idea that more computer resources in terms of central processing unit C
69. age areas and other attributes This chapter provides a detailed example of how to perform drainage analysis on a digital terrain model for development of an HEC HMS model Eight additional data sets are derived that collectively describe the drainage patterns of the watershed This information will be used to perform a preliminary delineation of the streams and subbasins The first five data sets in the grid representation are the flow direction flow accumulation stream definition stream segmentation and watershed delineation grids The next two data sets are the vectorized representation of the watersheds and streams and they are the watershed polygons and the stream segments The last data set the aggregated watersheds 1s used primarily to improve the performance in watershed delineation The following tasks will be performed in the presentation of this example Figures and tables numbers are not used as the information follows in the direct order of when the tasks and results are described Processing times for most tasks are shown based on a Pentium III 500 MHz with 256 MB of memory Besides the hardware specifications 145 Chapter 10 Example Application American River Basin 146 the terrain grid size is the most important factor in determining the time required to perform most of the operation The sample data for this exercise includes the DEM dem and gage outlet locations heclga shp T
70. al Characteristics Units Table Heading Grid Cell Parameter X Coordinates ModClark2K Shp Shg X Y Coordinates Shg Y Grid Cell Travel Kilometers Distance FlowLength Grid Cell Area S quare Mod Area kilometers Steps Select HMS gt Grid Cell Parameter File e Select SHG Method from the dropdown menu as shown in Figure Press OK 22 Mod Clark Method Select the method for Clark SHG Method Cancel Figure 9 26 Grid types e The SHG grid uses the Albers Equal Area projection as shown in Figure 9 27 Press Yes 127 Chapter 9 Hydrologic Modeling System 128 ModClark Output Projection Definition G Use Default ALBERS Projection No Figure 9 27 Default albers projection Select the cell resolution for the SHG grid at 2000 meters implied A grid cell resolution of 2000 meters 1s often suggested when working with radar rainfall At that resolution a grid cell has an area of four square kilometers if it resides entirely within a subbasin Along subbasin boundaries however a grid cell 1s often broken into several pieces which belong to several subbasins Press OK 2 Cell Size Select the cell size Cancel Figure 9 28 Grid cell resolution for SHG e Make a note of the filename and its location as shown in Figure 9 29 Press OK 2 ModClark Processing Figure 9 29 Grid cell parameter file location A separate view 15
71. and one output in the operation as shown below 22 Basin Centroid Computation SUBB asin Shp HydroDE b FlowD Fdirarid WehCentroid WishCentraid Help Cancel Press OK Select the Ellipse Method from the dropdown menu 2 Centroid Computation Method Select Method far Watershed Centro Computation Ellipse Method Cancel Bounding Box Method Flow Path Method Press OK A new theme WshCentroid Shp is created to represent the centroid locations 173 Chapter 10 Example Application American River Basin 2 wzheentraid S hp al lan gestfp Shp _ Elepointshp _ Heetgashp dl Projamer shp MidP aint Outlet River Shp 4 WaterShd Shp r1 hal The centroidal elevation is saved under the Elevation column in the Watershd Shp attribute table 2 Attributes of WaterShd Shp M 13374900 00 174 Chapter 10 Example Application American River Basin D Longest Flow Path e Select Basin Characteristics gt Longest Flow Path d Longest Flow Path Computation Wi aterS hd Shp Longestip LL c9 Review the input and output themes Press OK This step takes about 5 minutes 3 Longest Flow Path Computation 1 Press OK on confirmation screen The results of the longest flow path operation are shown below
72. another program called GageInterp HEC 1999 The precipitation grid format 1s 138 Chapter 9 Hydrologic Modeling System aligned with the grid cell parameter file The steps for developing the meteorologic model follow HMS Project Definition Component Data View Toole Help Project Mame GeoHMS Ex Description Gis Application from 5 zu Components Basin Model Meteorologic Model Control Specifications _ Component Description Basin model created with HEC GeaHMS v1 0 Beta Click component descnption double click to edit Figure 9 47 HMS Project with Basin Model From the HMS Project Definition window as shown in 47 select Component gt Precipitation Model New as shown in Figure 9 48 The result 15 shown in Figure 9 49 HMS Project Definition IE Lata View Tools Basin Model k Meteorologic Model lipen Control Specifications Help Description EE Delete m Components Import Figure 9 48 Met Model menu item e Enter the Meteorologic Model name as Radar and the Description as Grid based precipitation in Figure 9 49 Press OK 139 Chapter 9 Hydrologic Modeling System FW HHS New Heteorologic Model Meteorologic Model Radar Description Grid based precipitation T Director where meteorologic model will be stored d hmsprajseaHMS Ex Cancel Se
73. any incremental amount of water that flows into the depression will displace the same amount of water from the depression The steps to fill the depressions are shown below e Add unfilled DEM into the Main View using the Add Theme button see 39 Chapter 6 Terrain Preprocessing 40 2 al Amer meters 320 7 528 1528 7352 1 235 2 942 5 942 5 1149 8 EN 1149 8 1357 EN 1357 1564 3 BE 15643 1771 6 EN 177 16 1275 8 EN 197 2186 4 Figure 6 4 Depressionless DEM Select Terrain Preprocessing gt Fill Sinks when a MainView document 1s active e Confirm that the input of the RawDEM also referred to as the unfilled DEM is Amer meters The output of the HydroDEM 15 FillGrid see FillGrid is a default name that can be overwritten by the user e Press OK 2 DEM Filling Sinks Operations Amer meters _ x HydroDEM FilGrid Help Cancel Figure 6 5 Fill Sinks operation The result of the Fill Sinks operation is the Fillgrid theme as shown in Figure 6 6 where the lowest cell elevation is increased from 320 7 meters to 324 2 meters Chapter 6 Terrain Preprocessing ET UIT gt 324 2 531 1 5831 4 738 1738 944 8 944 8 1151 7 ENS 11517 1358 6 mg 1358 6 1565 5 EN 1585 5 1772 3 EN 0772 3 1272 2 EN 1979 2 2156 1 EM D ata Amer m
74. apter 7 Basin Processing Basin Subdivision A basin can be subdivided with the Ar Basin Subdivide tool The tool tip can be viewed by placing the pointer tool over Ar tool as shown in Figure 7 5 The tool tip indicates that the users can 1 Click on the stream to subdivide a basin or 2 Control key plus Click to remove unnecessary point The unnecessary point is often a residual from multiple basin subdivision and merge The basin subdivision Ar tool can be applied in three methods Figure 7 5 Basin subdivision Method 1 Basin Subdivision on Existing Stream An existing basin can be subdivided into two basins on an existing stream e Zoom in to the area of interest as shown in and make the SmallStrGrid theme visible by checking the box next to it this results 1n The SmallStrGrid theme represents grid cells that compose the stream network The existing streams are shown as blue lines according the River Shp theme 2 AmernHivl Amerrivd hp Outlet af River Shp Zoom to box i aterShd Shp CJ Sm strink arid facegrid fdirarid Figure 7 6 Zoom in prior to basin subdivision 68 Chapter 7 Basin Processing Select the tool Click on the cell of interest as shown in 52 AmerHiv Am erriv1 zhp AES WaterShd Shp af SmallStrGrid 11 No D ata strink grid facegrid
75. at can be overwritten by the user e Press OK 2 Flow Direction Computation HudraD EM fillgrid irrid Help Cancel Figure 6 7 Flow Direction operation The result of the Flow Direction operation 15 the FdirGrid as shown in Figure 6 8 2 Main iew _ Amer meters Figure 6 8 Flow Direction operation result Flow Accumulation This step determines the number of upstream cells draining to a given cell Upstream drainage area at a given cell can be calculated by multiplying the flow accumulation value with the cell area The steps to compute flow accumulation are shown below Select Terrain Preprocessing Flow Accumulation Chapter 6 Terrain Preprocessing e Confirm that the input of the FlowDirGrid is FdirGrid The output of the FlowAccGrid is FaccGrid see FaccGrid is a default name that can be overwritten by the user e Press OK 2 Flow Accumulation Computation rid Fdirarid z FAcclarid Help Cancel Figure 6 9 Flow accumulation operation The result of the Flow Accumulation operation is the FaccGrid as shown in Figure 6 10 Mainview faccgrid e 53258 s53258 106517 Em 106518 159776 EN 1528777 213035 BEN 212056 266294 D ata _ fdirgrid fillgrid Amer meters Figure 6 10 Flow accumulation operation result Stream Definition Th
76. atch points result 67 Chapter 7 Basin Processing 88 AmerHivi vil Batchpnts hp e 5 _ Elepointshp E _ Amerrivd BatchF oint MidP oint Outlet W River Shp iM i aterShd Shp Figure 7 44 Imported batch points in yellow or white As shown in Figure 7 45 BatchDone flags are set to 0 to indicate that the user can re run the Delineate at Batch Points menu item to delineate subbasin at the four newly added batch points 2 Attributes of Batchpnt shp Saye Saadet Point i 1 2246 i BatchPointl Faint These batch points will be processed if batch delineation is performed Figure 7 45 Batch Points attribute table Chapter 9 Stream and Watershed Characteristics CHAPTER 8 Stream and Watershed Characteristics HEC GeoHMS computes several topographic characteristics of streams and watersheds These characteristics are useful for comparison of basins and for estimating hydrologic parameters The user should compare and verify the physical characteristics with published information prior to estimating the hydrologic parameters The stream and watershed physical characteristics are stored in attribute tables which can be exported for use with a spreadsheet and other programs When more experience 15 gained from working with GIS data initial estimates of hydrologic parameters will be provided in addition to the
77. athname 5HG Pathname B Part SACRAMENTO Pathname Part PRECIP Fathname UNIT Replace Missing data with zero Time Shift in hours UTC local time OK Apply Cancel Figure 9 53 Gridded precipitation model options e To specify the Gridded Data File in Figure 9 53 press the Browse button and navigate to and select the D hmsproj GeoHMS EXl sac unit dss Enter the following pathname parts that are applicable to the sac unit dss file For Pathname A Part enter SHG for Pathname B Part enter SACRAMENTO for Pathname C Part enter PRECIP and for Pathname Part enter UNIT Check Yes to Replace Missing data with zero shown in Figure Control Specifications The control specifications component contains time related data HEC 2000 The following steps illustrate the creation of control specifications component with the time window and interval that are compatible with the precipitation HMS does not currently interpolate gridded precipitation to other time intervals the simulation must be performed at the same 1 hour interval as the gridded rainfall It identifies a time window from 29 February to 3 March 2000 The computational time interval 1s set at 1 hour The time related data input steps for the control specifications are shown below Chapter 9 Hydrologic Modeling System e From the HMS Project Definition window select
78. because of their widespread availability Source WWW UuSsgs gov WWW Water usgs gov Hydrologic Unit Code HUC The HUC contains the major watershed boundaries as published by the USGS The HUC shows watershed boundaries at 4 levels of detail ranging from local to regional drainage area Source WWNW uSgSs gOov Digital Line Graph DLG In addition to line representation of transportation data such as streets and railroads the DLGs include water features such as stream networks and irrigation ditches The DLGs are maintained by the United States Geological Survey USGS Source WWNW USgs gOV 23 Chapter 4 Data Collection 24 Stream Networks Stream networks are maintained by the Environmental Protection Agency EPA Many versions of the stream networks are available as the River Reach File RF1 the River Reach File and the National Hydrography Data set NHD Source Cpa com http nhd usgs gov Streamflow Gage Data Although streamflow gage data are natively non spatial the latitude and longitude coordinates of the gage are provided most of time The streamflow gage locations can be converted into a GIS data set by using the coordinate information The majority of streamflow gages are maintained by the USGS state governments and flood control districts The stream gages maintained by the USGS are organized by major basin names and the Hydrologic Unit Code These gages often provide th
79. c Grid Definition ix 33 192 State Soil Geographic Data Base 25 27 STATSGO 25 27 194 Stream Definition 43 44 45 153 154 Stream Segment Processing 49 158 200 Stream Segmentation 46 155 T Terrain Preprocessing 3 12 13 14 16 35 36 38 40 41 42 44 46 47 48 49 50 52 149 150 151 153 155 156 157 158 159 Threshold 45 Toggle GeoHMS 15 18 U Units ix 27 33 44 45 93 111 114 115 116 127 153 172 179 191 192 User Specified Centroid Location 101 Utility 14 36 187 W Watershed Aggregation v 50 51 159 Watershed Delineation 47 156 Watershed Polygon Processing 48 157
80. cial vendors Further the agreements require that users accept the provisions of the copyright restrictions of the commercial software components as noted in the following paragraphs CopyrightO 1996 ArcView GIS and Spatial Analyst Extension by Environmental Research Institute System Inc Rights Reserved BY USING OR COPYING THIS SOFTWARE USER AGREES TO ABIDE BY THE COPYRIGHT LAW AND ALL OTHER APPLICABLE LAWS OF THE U S INCLUDING BUT NOT LIMITED TO EXPORT CONTROL LAWS AND THE TERMS OF THE FOLLOWING LICENSE AGREEMENT THE HYDROLOGIC ENGINEERING CENTER SHALL HAVE THE RIGHT TO TERMINATE THIS LICENSE IMMEDIATELY BY WRITTEN NOTICE UPON USER S BREACH OF OR NONCOMPLIANCE WITH ANY OF ITS TERMS USER MAY BE HELD LEGALLY RESPONSIBLE FOR ANY COPYRIGHT INFRINGEMENT THAT IS CAUSED OR ENCOURAGED BY USER S FAILURE TO ABIDE BY THE TERMS OF THIS LICENSE The above information and the full License Agreement are presented for acceptance when the software 1s first used That information is also provided in Appendix E of this manual for reference Table of Contents TABLE OF CONTENTS ii Table of Contents 1V Table of Contents List of Figures IGURE 2 1 EXTENSIONS WINDOW WITH HEC GEOHMS 2 0 c ccc ccceccceccccecescecccscescsccescecesceseecesescecesescesescesesces 9 RESULT eant nas Sec dee T D dn 41 s FLOW DIRECTION OPERATION 42 FLOW DIRECTIO
81. created to overlay the subbasin and the SHG grid and perform the intersection as shown in Figure 9 30 Chapter 9 Hydrologic Modeling System 2 ModClark2k MadClarkzk Figure 9 30 Intersection between subbasins and SHG grid This operation creates a grid cell shapefile ModClark2K shp and a raster data set FlowLength for computing grid cell travel distances to the subbasin outlet as shown in Figure 9 31 2 AmerHivl IN Subbasin R150W120 5 696 sq mi 4 WiaterShd Shp 4 hod Clark 2k 0305 1 123 EN 1 133 1964 1561 295 2 95 4 757 4757 7 295 F low Len gth 1999 321 C 1299 321 38 3998 643 59 5597 964 78 EN 2997236 99 EN 556807 11 EN 11555525 1 EN 12555 25 15 E 15994 571 1 mE D ata _ Outlett shp hms 5 hp IN Subbasin R80W60 2 428 sq mi gremio eode Figure 9 31 Grid cell parameter file result The attribute table shown in Figure 9 32 displays the results for the selected cell 129 Chapter 9 Hydrologic Modeling System 2 Attributes of ModClark2k aeg HANS Akse arnt 0 10599500000 PT BABERE Figure 9 32 Grid cell parameter attribute table The resulting grid cell parameter file in ASCII format looks similar to Figure 9 33 PARAMETER ORDER Acoord Ycoord TravelLength Ar
82. d strink grid facegrid fdirgrid fillgrid B Subdivide a Basin e Make Heclga shp active on the ProjAmer window e Using the Identify tool on the streamflow gage with Station ID 1144190 e Notice that the reported drainage area is 171 sq miles 2 Identify Results Clear Clear All Zoom in on gage location e Use the Identify Area tool to find computed drainage area e Select tool With the SmallStrGrid visible click on the cells near the gage to compute drainage areas 166 Chapter 10 Example Application American River Basin 2 5 Frojamer shp Outlet River Shp i WaterShd Shp SmallStr rid _ strink grid _ facegrid _ fdirgrid e After searching nearby cells the cell shown below is an adequate location for an outlet The computed drainage area is The area 171 065 miles squared 2 Proj amp mer al lt Projamer shp Outlet Rmer Shp aterS hd Shp 1 Sm allStr rid strink grid facegrid fdirgrid fillgrid v E Bi Select the tool e Click on cell shown below to subdivide basin 167 Chapter 10 Example Application American River Basin 2 Proj amp mer Hecigashp Projamer shp Outlet River Shp Wi aterShd Shp Sm allStrsrid strink grid facegrid fdirgrid v v
83. d basin area The option A new threshold allows the user to specify a new threshold for the project The option Head basin area allows the user to specify a threshold such that the head subbasins are approximately equals to the threshold e Press OK ES Generate the Mew Project Construct the basic study area based new threshold Head basin area Figure 6 32 Generate project with options Use the default name ProjArea SHP as shown in Figure 6 23 60 Chapter 6 Terrain Preprocessing 2 Project Manager Theme Frajsrea Proparea 5 HP Cancel Figure 6 33 Project manager theme window Press OK to generate a new project in the ProjView document type named AmerRiv1 as shown in Figure 6 34 2 1 Amerrivd hp River Shp iM afi aterShd Shp _ fdirgrid ah Outlet Sm rid strink grid facegrid Figure 6 34 New project for hydrologic model In ProjView named AmerRiv1 the following data sets are extracted and created for the specified study area The extracted area includes the buffer zone in order to deal with the boundary conditions The data sets ending with Grid are raster data sets and the data sets with the shp extension are vector data sets in industry standard shapefiles format FillGrid represents extracted terrain for the study area FdirGrid represents the extracted flow direct
84. d documentation through a Cooperative Research and Development Agreement CRADA to engineer technology into commercial software The individuals involved are listed below From the Research Division of HEC Mr James Doan 15 a co developer of HEC GeoHMS and an author of this user s manual Dr Thomas Evans provided extensive input and guidance number of HEC staff helped in the testing and usage of the program Mr Arlen Feldman Chief of Research Division contributed valuable management and review of the program and documentation From ESRI Dr Dean Djokic Dr Zichuan Ye and Mr Sreeresh sreedhar contributed valuable software insight development and programming in conjunction with HEC From the University of Texas at Austin Dr David Maidment Dr Francisco Olivera and several graduate students contributed valuable research effort time and expertise Mr Darryl W Davis Director of HEC and Mr Jack Dangermond President of ESRI established the CRADA Mr Davis was the Director of HEC during the development of HEC GeoHMS Chapter 1 Introduction CHAPTER 1 Introduction In recent years advances in the Geographic Information Systems GIS have opened many opportunities for enhancing hydrologic modeling of watershed systems With an openness to share spatial information via the Internet from government agencies commercial vendors and private companies coupled with powerful spatial algorithms the integration of GIS
85. de from associating data sets with their intended roles as they are created the data management allows the user the ability to bring other data sets and assign a role for it For example if the user has developed the flow direction and accumulation grid in another program they can bring this data in as themes and assign their roles This 15 a good way to keep track of data as they are generated Another example is the flow tracing tool and area tool the Chapter 6 Terrain Preprocessing program knows which data layer should be operated on to provide the results I caesi cin the data management of themes on the left hand si signed themes on the right hand side The Null entry for the assigned theme indicates that the appropriate theme has not been created and assigned When the appropriate themes are created their names replace Null entry as shown Themes Used in Preprocessing Hydra EM NULL el FlowDiirGirid NULL Strearmilarid LinkGrid WiaterGrid NUL ml Watershed el River NUL Aggregedw atershed NULL Figure 6 2 Data Management window 37 Chapter 6 Terrain Preprocessing 38 3 Themes Used in Preprocessing Hydrol E fillarid fdirgrid Flow4cclrid faccarid Streamlarnid LinkGrid NULL m wW aterarid NUL e Watershed NUL m Fiver NULL A
86. del often serves as a simpler substitute in the analysis For study regions with moderate to high topographic relief the depressionless terrain model may be adequate for the analysis For low relief regions however depressionless terrain model often needs additional work to adequately represent the terrain For example a watershed with flat terrain often requires editing to force proper drainage location Until better data quality and editing techniques are available users may struggle with terrain data assembly It is important to identify the issues with the data so that the user knows and fixes the problems As an encouraging note many governmental institutions including the USGS and the EPA are working to develop seamless terrain information and streams and watersheds information which will ease the data assembly efforts Data Issues A number of issues have been identified to increase awareness as a first step in formulating a solution When assembling terrain data the user should address the considerations shown in Table 5 1 Table 5 1 Data Issues Descriptions and Potential Solutions 1 Low relief terrain With low relief terrain 1t 1s often difficult to delineate reliable drainage paths from relative average elevations Finer resolution terrain data should be considered for the flat region if it 1s available However finer resolution data has its tradeoffs with increased storage and longer computation t
87. e User s Documentation Figure 9 49 New meteorologic model e From the Add subbasins from basin model dropdown menu select AmerRiv1 Press Add button and the subbasins in the basin model are added to the Subbasin heading as shown in Figure 9 50 Press OK FH HHS HMeteorologic Model Subbasin List Edit Help Meteorologic Model Radar Add subbasin from basin model Add Delete Subbasin From Meteorologic Model 60 130 Delete Ej OK Apply Cancel Figure 9 50 Meteorologic model subbasin list 140 Chapter 9 Hydrologic Modeling System e With the Precipitation tab active select Gridded Precipitation from the Method dropdown list as shown in Figure 9 51 HHS Meteorologic Model land based precipitation UserHyetogaph Gridded Precipitation Figure 9 51 Meteorologic model methods Confirm Change Precipitation Method Figure 9 52 Confirmation of precipitation method Press OK to the confirmation of precipitation method as shown in Figure 9 52 141 Chapter 9 Hydrologic Modeling System 142 HHS HMeteorologic Model EE gt Edit Help Meteorologic Model Radar subbasin List Description Grid based precipitation Precipitation Eyvapotranepiration Methad Gridded Precipitation Gridded Data File D Shmspro GeoHMS_Ext unit dss Browse P
88. e graphics can be selected and deleted when the user is done examining them To delete the graphics select the graphic with a standard ArcView X Pointer tool or Select Edit Select All Graphics and select Edit Delete Graphics Description Delineate the watershed tributary to a user specified point Point Delineate Chapter 6 Terrain Preprocessing 56 Identify Tool Procedure Zoom in to the stream Select the Point Delineate tool Click Yes to enable snapping to a river or No to disable snapping 2 Point Delineation River Snap Selection Snap a point to a river section Snap Mo nat snap Cancel The result of this operation 15 saved in a point and polygon shapefiles Description Identify contributing area for any cell in distance units as specified in the View s properties Procedure Select the Identify Tool Click on the cell in question The drainage area in distance units at the cell is displayed in the lower left hand corner of the status bar as shown below The area iz 83 3454 miles squared Chapter 6 Terrain Preprocessing Hydrologic Model Setup The HMS Project Setup menu on the Main View GUI is responsible for extracting necessary information from the spatial database and creating an HMS project The approach for extraction involves specifying control points at the downstream outlet which defines the
89. e historical daily peak flow values and or annual peak flow values Source WWW USZS 2ZOV Digital Orthophoto Quarter Quads DOQQ Digital aerial photos with colors are available at various resolutions can be uses a background base map Source Various governmental authorities and commercial vendors Chapter 4 Data Collection Drainage Facilities Photographs Photographs can be taken of key drainage structures The photographs often include the areas looking upstream and downstream of the structures as well as the faces of the structures Source Field observations conducted by the engineers Street Data Street level data that 1s provided by the US Census Bureau often needs format conversion before it could be accessed though GIS software A number of data vendors have performed the format conversion as well as putting value added improvements Source United States Census Bureau and commercial vendors Soil Types Data The Soil Surveys Geographic Data Base SSURGO data contains good detail but 1s limited in coverage The State Soil Geographic Data Base STATSGO covers the entire USA but in less detail Source United States Department of Agriculture STATSGO and SSURGO CD ROM www ftw nrcs usda gov stat data html www ftw nrcs usda gov ssur data html Land Use Land Cover The USGS Land Use Land Cover LULC provides good coverage but may be dated Source 25 Chapter 5 Data Assembly CHAPTER 5
90. e river length for all subbains and routing reaches in River shp file as shown in The initial attribute table prior to any computations for River shp theme is shown in The computed river length is added as an attribute to the existing River shp file as shown in Figure 8 2 The length column in the attribute table 15 Chapter 9 Stream and Watershed Characteristics computed roughly from the raster representation of the stream This step will compute the river length more accurately with the vector representation of the stream 2 1 aterShd Shp lt lt Sm rid 1 D ata I strink grid facegrid fdirgrid fillgrid 2 Attributes of River 5hp Fete LE LLL 3130 Fete i E er 2743 Polline i oo d E E 1 3083 Polline U MEME l i NS JN 1913 Polline i ERR T T C Polline UR d MN 12i 1853 7 d O ME E A d d DN E 1261 Fobtine d d JEN ho 2480 Pete d B Boone D MNA ecce 499 ee 131 18i 1893 Figure 8 2 Initial attribute table for the river shapefile Steps e Select Basin Charateristics gt River Length as shown in Basin Characteristics Hiver Length Hiver Slope
91. ea END SUBRASIN GRIDCELL GRIDCELL GRIDCELL GEIDCELL GRIDCELL GRIDCELL GRIDCELL GRIDCELL GRIDCELL GRIDCELL GRIDCELL GRIDCELL GRIDCELL GRIDCELL GRIDCELL GRIDCELL END ReOWe 0 1043 1042 1042 edes 1042 104 104 1041 1041 1041 1041 lt 1044 1040 1040 1040 1029 luz 1049 1030 1031 1031 103 1026 1029 1049 1030 1031 103 1026 1031 1uU3z Many lines omitted 1 3 1 1 3 4 5 5 4 3 2 6 7 3 7444 2455967 7145 7020981 09464 2446025 551499 022047 106799 eae 097099 2061974 570029 2295500 0 0 C ce P239 D EA C CO C pz We 0 105995 450709 15594524 465 EI 7 119940 7 019840 3 69097 010195 675054 506599 444512 504456 Figure 9 33 HMS grid cell parameter file in ASCII format Distributed Basin Model 130 similar to lumped basin model distributed basin model has additional labeling that references the grid based subbasin in conjunction with the grid cell parameter file The ModClark transform and gridded precipitation must be used with distributed models Steps Select HMS gt Distributed Basin Model e Make a note of the filename and its location as shown in Figure 9 34 Press OK Chapter 9 Hydrologic Modeling System 2 HM
92. ectarlmad Extension About HEL GeoHMS5 Extension Extends Arcview and Spatial Analyst capabilities to develop hydrologic modeling inputs for HEC HMS Version 1 0 Constructed on Wed Jul 18 11 21 23 2000 Figure 2 1 Extensions window with HEC GeoHMS Chapter 2 HEC GeoHMS Installation In 1s not necessary to load the Spatial Analyst extension because GeoHMS will automatically load it When properly installed and loaded HEC GeoHMS will create two document types Main View and ProjView as shown in Figure 2 2 2 GIS Version 3 1 Project Window Help 2 Untitled HEC GeoHMS Document Types ArcView Standard Document Types Figure 2 2 HEC GeoHMS loaded within ArcView 10 Chapter 3 Working with HEC GeoHMS An Overview CHAPTER 3 Working with HEC GeoHMS An Overview HEC GeoHMS is a set of Arc View scripts developed using the Avenue programming language and Spatial Analyst It includes integrated data management and a graphical user interface GUI Through the GUI which consists of menus tools and buttons the user can analyze the terrain information delineate subbasins and streams and prepare hydrologic inputs The relationship between GIS HEC GeoHMS and HEC HMS 15 illustrated in The GIS capability is used for heavy data formatting processing and coordinate transformation The end result of the GIS processing 1s a spatial hydrology database that consists of the digita
93. ed in Figure 6 29 2 MainView _ mwehedmg shp lt af Wshedshp Shp wehedgrid strink grid sirgrid fdirgrid fillgrid v facegrid S vi Amer meters Chapter 6 Terrain Preprocessing Most Downstream Gage 26 sq mi Zoom to this box Figure 6 29 Gage Locations Zoom in to the region of the most downstream gage whose reported drainage area is 26 square miles sq mi The descriptions and procedures for useful buttons are explained in Table 6 1 MainView Button Descriptions and Procedures Button Find Area Descriptions and Procedures Description Find possible locations on each stream that have the closest but not exceeding drainage area to the user specified area This tool provides many candidate points with some points containing much smaller areas than the target area In order to narrow the number of candidate points the tool should be used when the user zooms to the area of interest Procedure In this case the downstream gage 15 close to three streams The user knows that the downstream gage drains 26 sq mi Using the E Area Find button the user searches within the zoomed in region for the locations along the streams whose area does not exceed the specified 26 sq mi With this information the user can define the watershed of interest 55 Chapter 6 Terrain Preprocessing 56 Select the threshold ty
94. em HEC HMS Chapter 1 discusses the intended use of HEC GeoHMS and provides an overview of this manual Chapter 1 Introduction Contents echnical Capabilities Program Features ntended Application of HEC GeoHMS ser s Manual Overview e Documentation conventions Technical Capabilities Hydrologic modeling has evolved to represent the subbasin in more detail that the traditional lumped approach where hydrologic parameters are averaged over the basin With the availability of radar rainfall and spatial data hydrologic modeling on a grid level has introduced a more detailed representation of the basin This distributive modeling approach utilizes the ModClark Peters and Easton 1996 Kull and Feldman 1998 hydrograph transformation method which tracks infiltration and excess rainfall on a cell by cell basis To meet the needs of both the traditional lumped and distributed basin approaches HEC GeoHMS has the capability to develop HMS input files that are compatible for both approaches The current version of HEC GeoHMS creates a background map file lumped basin model a grid cell parameter file and a distributed basin model The background map file contains the stream alignments and subbasins boundaries The lumped basin model contains hydrologic elements and their connectivity to represent the movement of water through the drainage system The lumped basin file includes watershed areas and reserves empty fields for hydrolo
95. er 9 Hydrologic Modeling System HHS Basin Model AmerRiv1 Edit Parameters Simulate View Help i 0 R 70w50 R110 0 f i UserPomt2 Pr R130100 LI serP oint43 20 Y 0 1120 m 1 160 130 1 t RBD _ lt 3 Hie dk ser Point MES me IM click and drag ta zoom in D Bl cliek to reset B Ameri Figure 9 43 HMS basin model schematic To fix the missing junction select the Junction element on the left side palette of the HMS Schematic screen and drag it onto the canvas and drop it at the outlet of subbasin RISOW120 Use HMS to connect subbasin R150W120 to Junction 1 Add routing reach R70 to connect Junction 1 to R70 as shown in Figure 9 44 136 Chapter 9 Hydrologic Modeling System 27 8 150 120 Junctian 1 Figure 9 44 Revision to basin connectivity with junction 1 To connect subbasin R160W 130 first break the connection of R160 and R60 Then insert the Junction element on the left side palette by dragging and dropping it at the outlet of subbasin R160W 130 Use HMS to connect subbasin R160W 130 to Junction 2 then connect reach R160 to Junction 2 and finally Junction 2 to reach R60 as shown in Figure 9 45 227 ABW 30 Er IserPointb M R160 p Junction 2 Figure 9 45 Revision to basin connectivity with junction 2
96. er value kilometers square kilometers real value 0 0 100 0 character string Xcoord YCoord TravelLength Area 191 Appendix Standard Hydrologic Grid Specifications APPENDIX D Standard Hydrologic Grid Specifications HEC 1s advocating the use of a standard geographic grid for hydrologic analysis and has defined grid for this purpose in the conterminous United States The proposed Standard Hydrologic Grid has cells of equal area throughout its coverage and 1s based on a coordinate system widely used for nationwide mapping of the US These properties offer significant advantages for hydrologic analysis with distributed watershed models and data development with geographic information systems Gridded Hydrology Many distributed input models including HEC s ModClark transform simulate hydrologic processes on a grid in effect breaking a watershed into a squares like a checkerboard and treating each square in that board as a separate and uniform but not necessarily independent region for hydrologic analysis Since the squares or cells in the checkerboard are much smaller than the watershed this permits more detailed modeling of hydrologic processes than 15 possible with lumped parameter methods like HEC 1 which treat the entire watershed as a uniform region Each cell in the grid can have unique values for the parameters required by the model and a unique value for precipitation depth at each time step as the model r
97. errain Preprocessing menu Fill Sinks is used to process and analyze the Flow Direction terrain It has the capability of Flow Accumulation processing the terrain in two ways step by step or batch processing It also has data management capability for tracking data sets as they are Watershed Delineation Chapter 6 Watershed Processing Stream Definition Stream Segmentation Stream Segment Processing Watershed Aggregation Full Preprocessing Setup HMMS Project Setup After the terrain has been processed Start New Project the HMS Project Setup menu is Generate Project used to extract the processed terrain information from the MainView The extracted information will be placed in a separate view called ProjView There are several options for extraction of terrain information Chapter 6 New Threshold For Selected Project Remove Selected Project tility The Utility menu contains Display Theme Tags miscellaneous tools dealing with mec assigning roles for data sets and developing graphical output Most users should not use this menu View to Image except for the graphic generation in shaded DEM to Image the last two menu items Set Theme Tag Value Remove a Theme Tag Chapter 3 Working with HEC GeoHMS An Overview Table 3 2 MainView buttons Find Area Find a number of locations that have the closest but not exceeding drainage area to the user specif
98. ersion e Sink _ centroid Shp wisheentroid S G Add Coordinates This step attaches geographic coordinates to hydrologic elements in the attribute tables of HMSPoint shp and HMSConnect shp The attachment of coordinates allows GIS data to be exported to a non proprietary ASCII format and still preserves the geographic information select HMS gt Add Coordinates Press OK H Background Map File The background map file captures the geographic information of the subbasin boundaries and stream alignments in an ASCII text file that can be read by HMS e Select HMS gt Background Map File 2 5 File creation The rnapfile map has been created in amp Make a note of the filename and its location Press 182 Chapter 10 Example Application American River Basin I Lumped Basin Model The lumped basin model captures the hydrologic elements their connectivity and related geographic information in an ASCII text file that can be read by into HMS This basin model should be used for hydrologic model with lumped not distributed basin parameters Select HMS gt Lumped Basin Model 2 HMS Basin file creation The Basin file mete basin has been created in e Make a note of the file name and its location Press Task III Hydrologic Modeling System 8
99. ersion of the program focuses on the extraction of physical characteristics instead of hydrologic parameters These physical characteristic tables can be exported and used externally to estimate hydrologic parameters When more experience is gained with applying GIS generated parameters it 1s anticipated that the program will suggest ranges for hydrologic parameters as appropriate Computing stream and Basin Characteristics watershed physical River Lenath characteristics under the Basin River Slope Characteristics menu as shown below is another responsibility of the ProjView document and is discussed in greater detail discussed in Chapter 8 Basin Centroid Centroid Elevation Update Longest Flow Path Lentroidal Flow Path 19 Chapter 3 Working with HEC GeoHMS An Overview HEC HMS Model Files The program produces four files that can be used directly with HMS If the lumped modeling approach 15 used then the user can generate the background map file and the lumped basin file If the distributed modeling approach 15 used then the user can generate the background map file the grid cell parameter file and the distributed basin file Generating HEC HMS model files under the HMS menu as shown below 1s another responsibility of the ProjView document and is discussed in greater detail in Reach amp utaM ame Basin ame ta 5 Units HMS Check Data Chapter 9 His Schematic HMS Lege
100. esccessesccesccuscenccesccessenssesccusseseesccussenseuecs 60 PROJECT MANAGER THEME WINDOW ccccssccsscceccesccsccuccesccscesccesscuscesccesccusseuccesccuscesscesceussenseuecs 61 NEW PROJECT FOR HYDROLOGIC MODEL ccccssccssccscccsccscesscesscscenccesscssesccesccessecsesseuscesccesseuscs 61 MAIN VIEW WITH TWO PROJECTS sspcccscsacssscssscaecaseoeseoaacensoeasosaassdcesnocaqoonseanpe EREE S E EREE R ER a 62 IGUBRE TET HASINNWEBBROGETDESUDD Dp MM M MEE 67 Table of Contents vi BASIN SUBDIVISION hse hse ese ese sie sese ese sese ese sese sese se 68 ZOOM IN PRIOR TO BASIN SUBDIVISION cscccsecccecccsscccssccuccencsssseeucsescsseessescsesseessseussescssesceenseuees 68 CLICK ON THE CELL TO SUBDIVIDE BASIN cccccccceecccescccecccecceucceusccuscsesscseceescsesseeceesesesceueceusesenss 69 abc MED T NAN T 9 69 BASIN SUBDIVISION CONFIRMATION eeeeeeeeeee eI ee ehe e nne hene rese hse rise ese ese rise ese sese s ees sese sees 69 gt BASIN SUBDIVISION RESULT 70 NEW SUBBASIN DELINEATION RH 70 ZOOM IN PRIOR TO BASIN DELINEATION svssssacesscurseatiwinsdesswerwensareindansswetenovenssddeusinnwensvedsddassiebeansvansses 71 DEFAULT OF NEW OUTLET wsssssssvenssnsuas
101. esceess 113 BASIN AUTONAME MENU TIENE URN UDIN 114 SUBBASIN AUTONAME RESULT oeste eetacesi to Savi gea sare ENAKEUN ENTUTA NEVERA VITE SR e UU VPE OSEE 114 lt HMS UNITCONVERSION OPTIONS OTRO 116 RIVER ATTRIBUTE TABLE POPULATED WITH HMS UNITS FIELDS cene 116 WATERSHED ATTRIBUTE TABLE POPULATED WITH HMS UNITS FIELDS cene 117 HMS CHECK DATA PROBLEMS eiecit iot haare erre tat UR PE pai Re RUE Ets Re ERR DR erre DEP RUPEE eed 119 HMS SCHEMATIC INPUT AND OUTPUT FILES ceceeeeeeeeetee he Ree em eene ene ee enses eei ie estes eere 120 INITIAL HMS SCHEMATIC RESULT cccsccsscsesccssccsccesccssccscsesccssccscssccssccsssesccssecscsescessscscsescescess 120 HMS SCHEMATIC POINT ATTRIBUTE TABLE ccccseccsscceccesccscesccesscescesccesccessenscusceussenccesseesseucees 121 HMS SCHEMATIC LINE ATTRIBUTE TABLE ctore toto euer Sepa Rete auem YR ap aEE Uo n eO x 121 HMS SCHEMATIC WITH 122 ADD COORDINATES MENU 123 POINT ATTRIBUTE TABLE POPULATED WITH COORDINATES 123 LINE ATTRIBUTE TABLE POPULATED WITH COORDINATES 124 BACKGROUND MAP FILE LOCATION HM
102. eters 3220 7 528 528 7352 735 2 942 5 942 5 1149 8 EJ 1122 8 1357 EN 1557 1564 3 EN 1554 3 1771 6 EN 217720685 1272 2 EN 10722 2196 1 to D ata Figure 6 6 Fill Sinks operation result Step by Step Process When performing this procedure the user needs to bring in a hydrologically corrected or depresssionless DEM from previous step With the step by step approach each step starts with offering a list of inputs that will be used to produce the output grid If the step by step procedure 15 performed in a sequential order program will be able to offer the correct data input for processing In a few instances when certain step are repeated or performed out of order it would be important to verify that the appropriate data sets are used Flow Direction This step defines the direction of the steepest descent for each terrain cell Similar to a compass the eight point pour algorithm specifies the following eight possible directions h4 east 2 southeast 32 Inn 4 south 8 southwest 16 1 16 west 32 northwest 64 north 128 northeast 4 The steps to compute flow directions are shown below Select Terrain Preprocessing gt Flow Direction 41 Chapter 6 Terrain Preprocessing 42 e Confirm that the input of the HydroDEM is Fillgrid The output of the FlowDirGrid is FdirGrid see FdirGrid is a default name th
103. from 3 5 km to 4 5 km in the US and the volume on one inch of precipitation varys from 252 to 417 acre feet The Albers equal area projection is probably the most common equal area projection and is supported by nearly all GIS packages State Plane and universal transverse mercator UTM projections are somewhat more widespread but do not have the equal area property and cannot provide a uniform coordinate system over as large an area as the Albers The USGS and other federal agencies use the same Albers projection for a number of national mapping products including the national atlas and the STATSGO soil database produced by the Natural Resource Conservation Commission Since the coordinates in these data sets can be converted directly to the Standard Hydrologic Grid data sampling for model parameter development is relatively simple Examples As examples of cell identification in the SHG system indices of cells containing points in the western US and the eastern US will be identified in the 1 km 2 km and 500 m SHG grids Western US The location 121 degrees 45 minutes west 38 degrees 35 minutes north near Davis California projects to 2185019 m easting 2063359 m northing in the specified Albers projection In the SHG 2km system the indices of the cell containing this point are 2185019 i floor floor 1092 5 1093 floor 7 floor 1092 5 2 j floor 5 floor 1031 7 1031 194 Appendix D
104. ggregedw atershed NUL E Cancel Figure 6 3 Data management with assigned themes Terrain Preprocessing Applying the GIS algorithms discussed below the terrain can be processed in two ways step by step or batch processing With the step by step approach as illustrated below data sets are derived after each operation Greater control over the results 1s obtained because the user verifies the results and makes decisions before proceeding For example prior to performing the stream definition it is good practice to use the Identify Area tool and check the contributing area at several locations This information on the area can help pick a threshold for adequate stream definition With the batch mode all of the inputs like the threshold and a few others are entered and then the program generates all of the data sets In a few instances the batch mode may pause and prompt for more input to complete the terrain process For example if there are too many outlets then the program will prompt for input whether stream segments serve as an outlet When using the batch mode there are some safeguards for changing the threshold to vary the detail of the stream definition After the batch processing 1s complete the user can use to the Identify Area tool to estimate a good threshold and then specify that threshold when setting up a hydrologic model Chapter 6 Terrain Preprocessing GIS Approach GIS approaches toward hydrol
105. gic parameters To assist with estimating hydrologic parameters tables containing physical characteristics of streams and watersheds can be generated If the hydrologic model employs the distributive techniques for hydrograph transformation 1 ModClark and grid based precipitation then a grid cell parameter file and a distributed basin model at the grid cell level can be generated Program Features HEC GeoHMS is a public domain extension to the ArcView GIS and Spatial Analyst extension ArcView GIS and its Spatial Analyst extension are available from the Environmental Systems Research Institute Inc ESRI HEC GeoHMS runs on the Windows 95 98 NT Chapter I Introduction platforms The following program features illustrate GeoHMS s functionality and ease of use Data Management GeoHMS performs a number of administrative tasks that help the user manage GIS data derived from the program The data management feature tracks thematic GIS data layers and their names in a manner largely transparent to the user Prior to performing a particular operation the data manager will offer the appropriate thematic data inputs for operation and prompt the user for confirmation Other times the data management feature manages the locations of various projects and also performs error checking and detection Terrain Preprocessing GeoHMS allows users to perform terrain preprocessing in a step by step fashion or in batch mode In the step by step
106. gic schematic of the watershed at stream gages hydraulic structures and other control points The hydrologic results from HEC GeoHMS are then imported by the Hydrologic Modeling System HEC HMS where simulation is performed GeoHMS 15 available for Windows 95 98 NT 2000 operating systems 14 SUBJECT TERMS 15 NUMBER OF PAGES Geographic Information System hydrology watershed precipitation runoff river routing flood 214 control water supply computer simulation 16 PRICE CODE 17 SECURITY CLASSIFICATION 18 SECURITY CLASSIFICATION 19 SECURITY CLASSIFICATION 20 LIMITATION OF OF REPORT OF THIS PAGE OF ABSTRACT ABSTRACT Unclassified Unclassified Unclassified Unlimited NSN 7540 01 280 5500 Standard Form 298 Rev 2 89 USAPPC V1 00 Prescribed by ANSI Std Z39 18 298 102 Geospatial Hydrologic Modeling Extension HEC GeoHMS User s Manual Version 1 0 July 2000 US Army Corps of Engineers Hydrologic Engineering Center 609 Second Street Davis CA 95616 530 756 1104 530 756 8250 FAX ww hec usace army mil Geospatial Hydrologic Modeling Extension HEC GeoHMS User s Manual Public Domain 2000 This Hydrologic Engineering Center HEC documentation and software was developed at U S Federal Government expense and 15 therefore the public domain Components of the HEC software were developed using proprietary commercial software The commercial portions of the HEC software may be purchased from the commer
107. ground map file location The resulting background map file in ASCII format looks similar to Figure 9 23 Chapter 9 Hydrologic Modeling System BoundaryMap Mapseqment closed 4a8150 1213550 48120 121350 46120 1281320 48090 1213520 48090 121290 many lines omitted River Map Map iegment open 4993 5 125325 499 65 125295 49995 125295 50145 125145 50 175 125145 many lines omitted Figure 9 23 HMS background map file example Lumped Basin Model The lumped basin model captures the hydrologic elements their connectivity and related geographic information in an ASCII text file that can be input to HMS This basin model should be used for a hydrologic model with lumped not distributed basin parameters Lumped basin models do not use gridded precipitation or the ModClark transform Steps e Select HMS gt Lumped Basin Model e Make a note of the filename and its location as shown in Figure 9 24 Press OK HMS Basin file creation The Basin hmetile basin has been created in amp geohmzs ex Varner Figure 9 24 Lumped basin model file location The resulting lumped basin model file in ASCII format looks similar to Figure 9 25 125 Chapter 9 Hydrologic Modeling System Basin AmerEivi Description Basin model created with HEC GceoHMS v1 U Last Modified date February 2000 Last Modified Time Ts
108. gure 6 15 Stream definition operation result Stream Segmentation This step divides the stream into segments Stream segments or links are the sections of a stream that connect two successive junctions a junction and an outlet or a junction and the drainage divide The steps to compute flow accumulation are shown below Select Terrain Preprocessing Stream Segmentation e Confirm that the input of the FlowDirGrid 15 FdirGrid and StreamGrid is StrGrid The output of the LinkGrid is StrLnkGrid see Figure 6 16 StrLnkGrid is a default name that can be overwritten by the user e Press OK 2 Stream Link GRID Definition fdirgrid Stream rid strarid Link Grid StrLnkGrid Cancel Figure 6 16 Stream segmentation operation 46 Chapter 6 Terrain Preprocessing The stream segmentation operation results in 13 stream segments as shown in StrLnkGrid theme in Figure 6 17 2 MainViewl v strink grid E m _ facegrid fdirgrid _ _ Amer meters Figure 6 17 Stream segmentation operation result Watershed Delineation This step delineates a subbasin or watershed for every stream segment The steps to delineate watersheds are shown below Select Terrain Preprocessing Watershed Delineation e Confirm that the input of the FlowDirGrid 15 FdirGrid and LinkGrid is StrLnkGrid The output of the WaterGrid i
109. he sample data is stored under the AmerRiverData directory on the CD ROM The completed ArcView project with the HMS model files illustrating the results of Tasks I to III 15 saved under AmerRiver directory on the CD ROM Task I Preprocess the Terrain Model 1 Open ArcView and load HEC GeoHMS 2 Setup the working directory with terrain and stream flow gage data 3 Perform drainage analysis by processing the terrain using the 8 pour point approach 4 Extract pertinent spatial data and setup a hydrologic model Task II Basin Processing 5 Revise subbasin delineation 6 Extract physical characteristics of streams and subbasins 7 Develop HMS Inputs Task III Hydrologic Modeling System 8 Setup an HMS model with inputs from HEC GeoHMS Chapter 10 Example Application American River Basin Tasks Task I Preprocess the Terrain Model 1 Open ArcView and load HEC GeoHMS e Create an empty folder called AmerRiver on the hard drive This folder serves as the working directory for your project In this case E AmerRiver e Open ArcView and create a new project as a Blank Project e Select the File gt Extensions e When the Extensions dialog appears scroll down until the HEC GeoHMS is visible 2 Extensions Available E tensions m EIE _ IMAGINE Image Support Cancel _ JPEG HFIF Imaae Support _ Legend Tool _ MrSID Image Support Reset
110. he stream s attribute table Similarly the basin characteristics will be stored in the subbasin s attribute table These two tables can be exported for external computations Chapter 8 This menu performs a number of tasks related to HMS These tasks include assigning default names for the reaches and subbasins unit conversion checking and creation of the basin schematic and HMS files generation Chapter 9 Same as those in the MainView 17 Chapter 3 Working with HEC GeoHMS An Overview Table 3 5 ProjView Buttons Same as those in the MainView 18 Toggle Same as those in the MainView GeoHMS Table 3 6 ProjView Tools Identify same as those in the MainView Area Same as those in the MainView Basin Subdivide existing basin or create new Subdivide basin at user specified point Profile Extract the stream profile with elevation based on the terrain model Batch Point Create a batch point shapefiles layer based on the user specified point Profile While the stream profile chart 1s opened Subdivide this tool allows the user to subdivide existing basin at user specified point along the profile Basin Processing In this step the user 15 provided with a variety of interactive and batch mode tools to delineate subbasins In the interactive mode the tools allow the user to see the delineation results assess outcomes and accept or deny the resulting delineation The interactive tools s
111. he result of the basin subdivision is shown in Figure 7 24 7 Chapter 7 Basin Processing 2 Amercrivd hp MidP aint Outlet River Shp i WaterShd Shp 1 Ho D ata strink grid _ facegrid New _ fdirgrid Subbasin Figure 7 24 Basin subdivision from a profile Split Basins at Confluences The Split Basins at Confluences menu item allows the user to subdivide a basin at a confluence For the situation shown 25 the menu item should be used instead of the interactive Ar Basin Subdivide tool Rules e Only one basin can be selected for each operation e This menu item can be used with a basin having multiple confluences Steps e Activate WaterShp shp theme on ProjView document e Select the basin containing the confluence as shown in Figure 7 25 78 Chapter 7 Basin Processing 2 Amerrivd hp MidPoint Outlet 4 River Shp Mf af i aterShd Shp CJ _ 11 No Data _ strink grid _ facogrid _ fdirgrid Figure 7 25 Subdivide basin at confluences e Select Basin Processing gt Split Basin at Confluences as shown in Figure 7 26 Basin Processing Basin Merge Hiver Merge Hiver Profile Split Basin at Confluences Import Batch Points Delin ate at Batch Points Figure 7 26 Split basin
112. he threshold must be defined as a percentage of the largest drainage area e Enter 1 to initiate the stream at 1 2 Full Preprocessing Enter percentage of largest area to initiate a stream stream threshold Cancel The full preprocessing operation creates the eight themes shown in Figure 6 28 53 Chapter 6 Terrain Preprocessing 54 2 MainView Strshpz shp Aggqwshzhpz shp Wshzhpz Shp ws hgridz strink rid 2 strgridz facegrid fdirgridz fillgrid2 EA E Amer meters 2207 527 8t 1527 967 735 235 233 942 942 5 1149 EN 1149767 1 B 1557 033 15 BE 15543 1771 2774557 19 Figure 6 28 Full preprocessing setup results Data Exploration with Buttons and Tools This section discusses the buttons and tools that the user may need to explore and derive data The buttons and tools allow the user to find the drainage area at a point or find the point that has a specified drainage area The tools also allow the user to draw a flow path from a specified point and delineate the area tributary to a point This functionality allows the user to compare the GIS results with published results In the following example a streamflow gage with specified drainage area will serve as the published data source zin e Add the theme gage shp with the Add Theme button There are four gages in this data set as display
113. hould work quickly For example the user sees the result of the merger of smaller basins together or subdivision of a larger basin When the user performs interactive basin processing the program will prompt the user to confirm the results A number of other interactive tools allow the user to delineate a basin from a stream profile subdivide basin at a Chapter 3 Working with HEC GeoHMS An Overview stream confluence and create a basin where a stream does not exist In the batch mode the user can supply the outlet locations and the program will delineate subbasins at those locations but without interaction to view and revise Basin processing is one of the Basin Processing responsibilities of the Basin Merge ProjView document and is Hiver Merge discussed in greater detail Fiver Profile discussed in Chapter 7 Split Basin at Confluences Import Batch Points Delin ate at Batch Points Stream and Watershed Characteristics When the streams and subbasins delineation have been finalized the user can extract their physical characteristics The stream physical characteristics such as length upstream and downstream elevations and slope are extracted from the terrain data and stored as attributes in the stream table Similarly the subbasin physical characteristics such as longest flow lengths centroidal flow lengths and slopes are extracted from the terrain data and stored as attributes in the watershed table The current v
114. idment formulated a watershed data structure that would link GIS and hydrologic models From that time the definition and content of the GIS and hydrologic data structures evolved into a hydrologic GIS preprocessor PrePro Taking advantage of the wealth of terrain and geographic data readily available over the Internet and from government agencies PrePro delineates streams and watersheds and builds the hydrologic model structure for HEC HMS PrePro was the predecessor to HEC GeoHMS The development of PrePro at the University of Texas was partially supported by HEC via the Corps Civil Works R amp D program The effort also received substantial support from the Texas Department of Transportation as well as support from other national and international agencies PrePro development at the Center for Research in Water Resources at the University of Texas has been directed by Dr Francisco Olivera GeoHMS has been developed by HEC and ESRI as a component of a Cooperative Research and Development Agreement between those two organizations Dr Maidment Dr Olivera and others at the Center for Research in Water Resources have provided valuable assistance for the development of GeoHMS Other GIS products that have been released are under development by HEC include HEC GeoRAS a GIS utility for use with the HEC RAS river hydraulics program and HEC GeoFDA a GIS utility for use with the HEC FDA flood damage analysis package For several years
115. ied area This tool provides many candidate points In order to narrow the number of candidate points the tool should be used when zoomed into the area of interest Toggle Toggle the HEC GeoHMS tools ON OFF GeoHMS When it is in the ON position HEC GeoHMS tools are enabled When it 1s in the OFF position tools from other extensions are enabled Access context sensitive online help on any tools or menus Select the tool and Press it on any tools for online help To 3 3 MainView Tools Flow Trace Trace the flow path downstream of a user specified point for visualization purposes Point Delineate the watershed contributing to a Delineate user specified point Identify Identify contributing area in units as Area specified in the View s properties distance unit field Specify Specify the downstream outlet and or Project upstream source point for extraction of Point terrain information 15 Chapter 3 Working with HEC GeoHMS An Overview Contour This 15 an ArcView tool that 1s useful in HEC GeoHMS This tool draws contours at the user specified point Hydrologic Processing 16 2 ArcView GIS Version 3 1 Hydrologic processing is performed in the ProjView document which is generally responsible for hydrologic model construction and setup The tools available in the ProjView GUI are shown in Figure 3 3 able 3 6 able 3 4 Table 3 5 and 6 Typically the user proceeds from Basin
116. igure 8 39 Longest flow path result The flow path attributes are written to both attribute tables for Longestfp shp and WaterShd shp as shown in and respectively 106 2 Attributes of longestip Shp beet Chapter 8 Stream and Watershed Characteristics Poly ine 2 11865000 0 093 0 081 8449 037 1971 0000 4 6 152460000 0034 0 067 5890509 2181 0000 712569000 D18 s 0117 3434924 16 1 0000 essem 8 15155000 0 087 0096 4108 600 _ 1873 0000 ee 10 1056200 i 0 187 2732498 15530000 1 1059 8000 0193 2020 660 1433 0000 DE 3 9259000 DITS s 0186 3923483 1491 0000 1 Lose 12 145120001 0 083 519082 2130 0000 Popline 131 14118000 0128 3998 011 _1996 0000 4 z 2 Attributes of Shp Se ta A inest 41940 00000 15660 00000 18211000 16246000 0034 __ 0 067 5890 509 181 0000 12000 00000 1509 5000 12563000 01185 0117 3434324 1661 0000 11520 0000 15972000 18165000 UCM 0 096 4108600 18730000 5580 000000 14565000 10562000 018015 ____ 0180 2792498 15630000 5760 000000 10921000 10538000 02145 ____ 0183 2020660 14330000 11520 0000 12232000 8253000 1 ULTRI 0186 3833483 1491 0000 23220 00000
117. iles to where ArcView was installed Typically Arc View is installed in C esri Av_ gis30 Arcview or otherwise referred to as SAVHOME the following files to the specified ArcView sub directories These files are saved under the Manual Installation directory on the CD ROM Program Files Specified Locations HEC GeoHMS avx AVHOME ext32 G21 dll 1132 DirRemove exe A VHOME bin32 Chapter 2 HEC GeoHMS Installation Geohms hlp A VHOME help Geohms GID AVHOME help Geohms CNT AVHOME help Hmspoint avp A VHOME symbols Hmsmarker avl A VHOME symbols Hmsline avl A VHOME symbols Hrap_alb shp A VHOME tools Hrap_alb shx A VHOME tools Hrap_alb dbf A VHOME tools GeoHMS readme txt A VHOME ext32 Loading HEC GeoHMS Once HEC GeoHMS 15 installed it can be loaded within ArcView To do this open ArcView ArcView extensions are loaded through the File menu on the main ArcView window Select the File gt Extensions menu item In the Extensions dialog that appears scroll down until the HEC GeoHMS is visible Click on the name label HEC GeoHMS to access the About information as shown in Check the box to turn it on Press OK to close the dialog and watch the lower portion of the window for the installation notes 22 Extensions Available Extensions BRS IMAGINE Image Support m _ JPEG Image Support Legend Tool MrSID Image Support Reset Image Support a s D Praj
118. imes Other possible approaches include imposing the published stream alignment onto the terrain 3l Chapter 5 Data Assembly 2 Man made Man made structures like dams often alter structures the flow direction because the water surface prevents the mapping of the reservoir bottom In addition when the terrain data get filled the terrain 1s represented as a flat surface behind the dam A potential way to deal with this situation would be to put an artificial notch at the dam and carve a stream on to the terrain 3 Missing elevation Missing elevation data that often exist data along the edges and can be filled with interpolated values from neighboring elevations Bad elevation data due to re sampling effects and other causes can be fixed with spot elevation editing on a cell by cell basis or by region 4 Subsidence and The ground surface may subside due to other Environmental overdraft of groundwater Recognizing Impacts when the terrain data were developed the terrain data should be checked for subsidence Hydrologic Coordinate System Specifications 32 Transforming spatial data into a common coordinate system ensures proper alignment of various data sets for spatial analysis Coordinate system transformation often leads to map distortions of direction distance shape and area From a hydrologic perspective where the terrain and precipitation are important a suitable coordinate system should preserve area
119. improve the performance in watershed delineation The terrain preprocessing 1s performed in the Main View The objectives of the terrain preprocessing are described below The terrain 15 processed and analyzed using the 8 pour point approach to determine flow paths The terrain analysis 15 computer intensive and some steps may require several hours depending on the sizes of the data and computer resources e After the terrain preprocessing is completed the resulting data sets serve as a spatial database for the study With the information centralized in the spatial database pertinent data sets can be extracted for subsequent work on building the hydrologic models Preliminary watershed and stream delineation provides results that can be verified with published information to detect possible errors in the terrain model If errors are detected in the terrain model the DEM should be edited outside of the program When the DEM has been revised to better represent field conditions 1 should be processed again to update the spatial database This chapter will discuss the terrain preprocessing features and functionality HMS model setup and related utilities Contents eatures and Functionality Data Management errain Preprocessing 35 Chapter 6 Terrain Preprocessing Features and Functionality 36 e Arc iew GIS Version 3 1 En e zb FIX A T The HEC GeoHMS extension adds features and functionality t
120. in Figure 6 21 2 Wishedshp Shp hed grid strink grid strarid facegrid tdirgrid fillgrid Amer meters Figure 6 21 Watershed polygon processing operation result Stream Segment Processing This step converts streams in the grid representation into a vector representation The steps to vectorize stream segments are shown below Select Terrain Preprocessing Stream Segment Processing Confirm that the input of the LinkGrid 15 StrLnkGrid and FlowDirGrid is FdirGrid The output of the River is River see River is a default name that can be overwritten by the user Press OK 2 Stream Segment Processing LinkGrid strink arid fdirgrid zs He sd Help Cancel Figure 6 22 Stream segment processing operation 49 Chapter 6 Terrain Preprocessing 50 The stream processing operation vectorized the grid based streams into line vectors as shown in the River shp theme in Figure 6 23 2 MainView Riwer shp Wzhedshp Shp wis hed grid strink grid strgrid facegrid fdirgrid fillgrid Amer_meters Figure 6 23 Stream segment processing operation result Watershed Aggregation This step aggregates the upstream subbasins at every stream confluence This is a required step and 1s performed to improve computational performance for interactively delineating subbasins and to enhance data extraction This ste
121. in Figure 8 27 101 Chapter 9 Stream and Watershed Characteristics 102 2 1 langesttp Shp we heentroid S hp WaterShd Shp CJ _ Batehpntshp _ Gage shp _ Elepointshp Figure 8 27 Selected subbasin for User Specified method e Zoom in to the selected subbasin as shown in e Open WaterShd Shp attribute table as shown in Figure 8 29 2 Ameir lan gestfp Shp al vuzhcentroid S hp WiaterShd Shp _ Batchpntshp _ Gage shp _ Elepointshp amp dl Figure 8 28 Zoom in to the selected subbasin Chapter 9 Stream and Watershed Characteristics Attributes of WaterShd Shp Lm att et Ae o 18795500 00 pi 41940 00000 1487 0000 E 8838300 nOn 25320 00000 1545 2000 i cT EM DF c ae cox ian ua E MT M rn 5
122. ined by its outlet A watershed can also be defined by an outlet and one or more source points which represent inflows from other drainage basins The watershed outline is delineated by GeoHMS and a project view 15 created which contains the newly delineated subbasins or project model e Add the streamflow gage theme called HECIga shp to the MainView to help determine the outlet location e Make the HECIga shp active and identify gages shown below 2 Mainview Hecigashp wehedmg shp Rmer zhp Wi zhedzhp Shp ws hed grid strink grid strgrid facegrid fdirgrid fillgrid Ee sk 8 Amerriver dem Highlighted gage e The identified gage has a drain area of about 493 sq miles under the Drain area heading 2 Attributes of Heclga shp 39 0567 i 1 20 4063 114 18020128 PK i RRSREDRRRREREKRRRENRESRESRERRASRERARRERRRRSESERSAMRSEmARERD RARNSSRAUSREERRSREREUARNNERTGRRRAEKNAESEROSREBRRRNSRRERRSEEMAGES SERERE EEERRRRRRARRNURRAS SURRRSRREIRRRNRORRNRERARSREREEA Usus __ AMADOR 4 385714 12017715 10 5 ELDDORAD 356 388239 1205383 171 18020129 USGS jELDORAD 74 3876367 1203275 1933 1 180200128 USGS ELDORAD 72 388183 120 3642 28 18020123 K e USGS iPLACER i 54 389361 1210228 342 180201208 160 Chapter 10 Example Application American River Basin e Zoom in on the gage and make the StrinkGrid theme vi
123. ion for the study area StrLnkGrid represents extracted stream segments for the study area SmallRivGrid is an additional grid theme created using 10 of the specified threshold It contains denser stream representation for visualization purposes WaterShp Shp represents the extracted subbasins for the study area 61 Chapter 6 Terrain Preprocessing River Shp represents the extracted stream segments for the study area AmerRivl Shp contains project outlet and source point that defines the study area Additional HMS projects or Basin Models can be generated from the original set of preprocessed data sets As illustrated in Figure 6 35 and Figure 6 36 igure 6 36 the user can extract the pertinent data sets from the Main View to create another project The benefit of this setup is that it allows the user to preserve the original data sets and work on multiple projects 2 MaimViewl Mo Active Project Frojpnts shp ouie m Source lt Project A _ wzhedmg shp al lt N Wzhedshp Shp 1 _ wehedgrid strink grid _ strgrid _ facogrid _ tdirgrid fillgrid Amer meters Figure 6 35 MainView with two projects i eere Lim n 62 Chapter 6 Terrain Preprocessing 2 AmerHiv2 Amerrivz zhp d Outlet E Source Ww River Shp i yf WiaterShd Shp C
124. irable estimates of the basin centroids Rules This method works only on subbasins of 2 000 000 cells or less Steps e Activate the WaterShd Shp theme e Select the subbasin as shown in Figure 8 17 2 AmerRir 1 al vuzhcentraid S hp e yf w aterShd Shp i age shp _ Elepointshp amp Am erriv1 zhp BatchFoint Figure 8 17 Basin centroid with ellipse method e Open WaterShd Shp attribute table The highlighted row belongs to the selected subbasin Notice that the centroid elevation is 1633 7 977 Chapter 9 Stream and Watershed Characteristics 2 Attributes of WaterShd Shp Aa des 1 2 0 1501000 ADM 2 898300000 04 28320 00000 1545 200 Polygon 0 6288200000 RT 0 15660 00000 18211000 Pekgon 5 0 0i 438110000077 D 1200000000 15095000 me 01 2 385830000 11182000000 1597 200 DA dezao AO 8980 000000 1456 5000 LONGE 4 1104300 000 0 5760 000000 10821000 0 4 3690000 000 9 0 11520 00000 12232000 D 2 3779100 13 D 12050 00000 16054000 O S S E o E EE0 e e eeeePB B B 0 S L0 S
125. is step classifies all cells with flow accumulation greater than the user defined threshold as cells belonging to the stream network Typically cells with high flow accumulation greater than a user defined threshold value are considered part of a stream network The user specified threshold may be specified as an area in distance units squared e g square miles or as a number of cells The flow accumulation for a particular cell must exceed the user 43 Chapter 6 Terrain Preprocessing 44 defined threshold for a stream to be initiated The default is one percent 196 of the largest drainage area in the entire basin The smaller the threshold chosen the greater the number of subbasins delineated by Geo HMS The steps to compute stream definition are shown below e Select View gt Properties this results in Figure 6 11 e The Map Units are the X and Y coordinates units of GIS themes units In this example the horizontal unit of the DEM data units 1s measured in meters Specify the Map Units as meters from the dropdown menu e The Distance Units are the reporting units in ArcView In this example the Distance Units are chosen as miles so that the information generated from ArcView can be compared with the stream flow gage drainage area reported in square miles Specify the Distance Units as miles from the dropdown menu Press OK and then save the project 2 View Properties M Creation D ate
126. l elevation model DEM soil types land use information rainfall Currently HEC GeoHMS operates on the DEM to derive subbasin delineation and prepare a number of hydrologic inputs HEC HMS accepts these hydrologic inputs as a starting point for hydrologic modeling With the vertical dashed line separating the roles of the GIS and the watershed hydrology HEC GeoHMS provides the connection for translating GIS spatial information into hydrologic models 11 Chapter 3 Working with HEC GeoHMS An Overview Overview Watershed Hydrology Raw GIS Data Grid Format SHG amp HRAP y Preprocessed HEC HMS Spatial Hydrolo c Database DEM RF1 Watershed amp s River Land Use Characteristics Radar Rainfall Figure 3 1 Overview of GIS and hydrology programs The following contents describe the major steps in starting a project and taking it through the GeoHMS process Contents e Data Processing e Data Collection e Data Assembly e Terrain Preprocessing e Hydrologic Processing e Basin Processing e Stream and Watershed Characteristics e HMS Model Files e Hydrologic Parameters and HEC HMS Data Processing Data Collection With the volume of spatial data available it is important to identify the data that will meet project needs Spatial data comes in many formats resolutions intended uses quality and prices Prior to collecting data 12 Chapter 3 Working with HEC GeoHM
127. lGrid theme and selecting Theme Properties 2 Theme Properties Theme Mame Source e Samerne Prometa 30 Rows 1309 Cols 2094 Left 61260 Right 1560 Bottom 66380 105630 Flaat Status Permanent Commenta LreatedBuy HMS PR PrajecES erw ark Cancel Locking Task Basin Processing 5 Revise subbasin delineation A Merge Basins This process merges selected subbasins into one 164 Chapter 10 Example Application American River Basin e Make the WaterShp Shp active by clicking on the theme with the pointer tool The active theme appears raised e Use the select tool and select the two subbasins shown below 2 PropAmer Select this subbasin i Projamer shp Outlet River Shp Wiater amp hd Shp 4 SmallStrerid strink grid _ facegrid _ fdirgrid Select this subbasin e Select Basin Processing Basin Merge e The result of the merged subbasin is shown with red outline Press Yes to accept the resulting merged subbasin Merge Selected Basins 2 Confirm to merge displayed basins The result of the merged basin is committed as shown below 165 Chapter 10 Example Application American River Basin 2 Hecdgashp Projamer shp Outlet River Shp iM 4 WaterShd Shp Sm allStre ri
128. lected and used in a variety of ways Understanding how data are used provides many important guidelines in data collection When the data 1s intended as input in the program it should be collected with attention given to its accuracy resolution validity of data source and quality of documentation Oftentimes when the best available data are not adequate the appropriate course of action will be to develop data that meets project specifications instead of putting efforts collecting data In hydrology the terrain data 15 critical because it 1s used to determining drainage paths and physical characteristics When data are not used as input they often serve many useful roles such as reference information documentation and visualization and should be collected Reference Information for Results Validation For example the stream alignments hydrologic unit code and streamflow gage with drainage area are useful published reference information for comparing and validating the GIS delineated streams and subbasins 21 Chapter 4 Data Collection Documentation of Field Conditions GIS data can be collected and used with existing spatial data to document field conditions For example photographs of drainage structures as shown in Figure 4 1 and other field conditions can be photographed and geographically located with the street data to more effectively document these facilities and show their spatial relationships 42 d
129. logy and parameters For example 131 Chapter 9 Hydrologic Modeling System HMS can be used to change the connectivity and eliminate add and revise hydrologic elements and their properties The HMS project definition requires Basin Meteorology and Control Specifications components HEC 2000 The steps for setting up these three HMS components are discussed below Directory Setup Create the HMS project first and then copy the background map file basin model file and grid cell parameter file 1f appropriate into D hmsproj GeoHMS Ex1 HMS Use Start HMS Select File gt New Project on the HMS PROJECT DEFINITION screen e Enter the Project as GeoHMS and Description as GIS Application from HEC GeoHMS as shown in Figure 9 36 e Press OK HHS New Project OR gt Project GeoHMS Ex Description Gis Application from 9 S Directory where project will be stored hmspro aeoHMS Ex Browse Cancel Help Enter a description for the new project Figure 9 36 New HMS project definition window Basin Model Import the Basin Model with the following steps On HMS PROJECT DEFINITION screen select Component gt Basin Model gt Import as shown in Figure 9 37 132 Chapter 9 Hydrologic Modeling System FH HMS Project Definition aM Data View Tools Help Basin Model Open Meteorologic Model New Con
130. low 2 Mainview vil strgrid _ faccgrid _ fdirgrid fillgrid Amerriver dem Zoom in to display the details of the grid cells that make up the stream definition grid 154 Chapter 10 Example Application American River Basin E Stream Segmentation e Select Terrain Preprocessing gt Stream Segmentation e Confirm that the input of the FlowDirGrid is FdirGrid and StreamGrid is The output of the LinkGrid is StrLnkGrid StrLnkGrid is a default name that can be overwritten by the user e Press OK This step takes about 30 seconds 2 MainView strink grid 155 Chapter 10 Example Application American River Basin F Watershed Delineation e Select Terrain Preprocessing gt Watershed Delineation Confirm that the input of the FlowDirGrid 1s FdirGrid and LinkGrid is StrLnkGrid The output of the WaterGrid is WshedGrid WshedGrid is a default name that can be overwritten by the user Press OK This step takes about 6 minutes 2 Main iew grid 156 Chapter 10 Example Application American River Basin G Watershed Polygon Processing 2 MainViewl select Terrain Preprocessing Watershed Polygon Processing Confirm that the input of the WaterGrid is WshedGrid The output of the Watershed 15 Wshedshp Shp Wshedshp Shp is a default name that can be overwritten by the user Press OK This s
131. m 2 HMS Schema Consistency Checking FiverLink ubBasin watehdShp rl VIPoints 1 O d w shLentraid JwshcentoidShp e Help Cancel Figure 9 10 HMS Check Data Input and Output Files e Make a note of the filename and its location as shown in Figure 9 11 Press OK 25 HMS Schema Consistency Checking The skeletization check file 5 kel onsEhk tet has been created In e Ameri Figure 9 11 HMS check data result file location e Open the results file with a text editor and review the results The Checking Summary at the end of the file shows that 4 of the 5 items checked have no problems see Figure 9 12 The VIP Relevance check shows two problems The VIPs very important points represent locations of basin subdivision outlets centroids etc Sometimes a few VIPs are no longer relevant or needed because the basin outlets may have changed as a result of basin processing CHECKING SUMMARY 3E 3E 3E 3E 3E 3E 3E 3E 3E 3E 3E 3E 3E Unique names problems River Containment no problems Center Containment no problems River Connectivity no problems UIP Relevance total of 2 problems Figure 9 12 HMS check data result summary 118 Chapter 9 Hydrologic Modeling System e Scroll up the file and find that problems exist with and BatchPoint2 as shown in Figure 9 13 After examining the subbasin delineati
132. m ee AME ANS 27719882 13859939 4878 599 6466 522 3892 709 Figure 9 9 Watershed attribute table populated with HMS units fields HMS Data Check This step checks the data sets for consistency in describing the hydrologic structure of the model For example the program checks for unique names for the reaches subbasins and outlet points In addition the program also checks that the rivers and centroids are contained within the subbasins and that rivers are connected with relevant points created in the basin processing step This 15 desirable for placement of the hydrologic elements names and connectivities on the HMS basin schematic In general the program keeps track of the relationship between the stream segments subbasins outlet points and other entities These checks are necessary because the relationships between hydrologic elements may have been broken by unintentional use of the tools The program checks every spatial feature in the River shp WaterShd shp Amerrivl shp and Wshcentroid shp data files It produces a text file SkelConsChk txt that presents the results on each feature and summarizes the results This step does not fix any of the problem However the user can view the result and fix the problems manually in HEC GeoHMS or HMS Steps e Select HMS gt HMS Check Data e Review the input data sets as shown in Figure 9 10 Press OK 117 Chapter 9 Hydrologic Modeling Syste
133. n Stream Definition select View Properties The Map Units are the data units In this case the DEM data units are measured in meters Specify the Map Units as meters The Distance Units are the reporting units in ArcView In this case the Distance Units are chosen as miles so that the information reported from ArcView can be compared with the streamflow gage drainage area reported in square miles Specify the Distance Units as miles Press OK 2 View Properties M ame Creation Date Monday March 2000 03 04 22 Cancel Creator Units meters Distance Units BRR Projection Area OF Interest Background Color Select Color Comments Save the project as AmerRiver apr in the working directory E AmerRiver Select Terrain Preprocessing gt Stream Definition Confirm that the input of the FlowAccGrid 15 FaccGrid The output of the StreamGrid is is a default name that can be overwritten by the user Press OK Select the threshold type as Area in Distance Units squared Enter the threshold for stream initiation at 50 square miles 153 Chapter 10 Example Application American River Basin e Press OK This step takes about 30 seconds The largest drainage area iz 1855 34 miles squared Cancel The result of the Stream Definition operation is StrGrid shown be
134. nd Add Coordinates Background Map File Lumped Basin Model Grid Cell Parameter File Distributed Basin Model Hydrologic Parameters and HEC HMS 20 When GeoHMS generated files are brought into HMS the user has a partially completed HMS model To complete the HMS basin model hydrologic parameters need to be estimated and entered using editors provided in HMS In addition the user can add or remove hydrologic elements and their connectivity to reflect difficult modeling areas Finally the user needs to develop a Meteorologic Component to represent the precipitation and a Control Specifications Component to define the time window and other time related specifications With these three model components completed the user can refer to the HMS manual to make a simulation run and calibrate the hydrologic model Chapter 4 Data Collection CHAPTER 4 Data Collection The purpose of this chapter 1s to illustrate some of the ways spatial data are used in hydrology By understanding how the data sets are utilized the user can focus adequate time effort and attention on the appropriate data set When collecting data the user can assess the quality of the data and its metadata to meet project specifications This chapter also provides a list of data types descriptions and their sources as a starting point for collecting data Contents Data Usage Data Types Descriptions and Sources Data Usage Spatial data are col
135. ng tiled USGS s DEMs into a unified DEM grid The DEM assembled from the USGS represented by elevation averages at regular intervals may not accurately represent stream locations and watershed boundaries For example stream and watershed delineation sometimes does not coincide with published data sources like the EPA s 1 and the USGS s watershed in the Hydrologic Unit Code HUC A hydrologically corrected terrain model must represent accurate stream patterns across the landscape stream alignments topographic ridges stream confluence internal drainage areas and drainage facilities Many factors such as cell resolution accuracy topographic relief and drainage facilities deserve careful considerations because they often affect the quality of the terrain model In theory combining GIS data sets of different Chapter 5 Data Assembly resolutions 1s generally not recommended because of the difficulty in assessing the accuracy and the precision of the resulting data set In practice however combining data sets of various resolutions 15 necessary due to lack of uniform data and data coverage In contrast to the effort required for the hydrologically corrected DEM the depressionless DEM is simply constructed using automated algorithms to fill in the sinks or depressions in the assembled DEM Because of the complexity and effort required for constructing a hydrologically corrected terrain model a depressionless terrain mo
136. o standard ArcView menus Terrain Preprocessing HMS Project Setup and Utility buttons and pn are added to the standard ArcView GUI as shown in Figure 6 1 A number of capabilities related to terrain processing are E the Terrain Preprocessing menu Once the terrain processing 15 complete the data can be extracted to support hydrologic model creation via the HMS Model Setup menu The Utility menu allows users to perform some limited administrative tasks in assigning or changing a theme which 1s to be identified and used by the program Each theme will be assigned a unique name or by which it will be known to the program The tags are names associated with themes that identify the role of the theme in the program Buttons perform tasks after they are activated tools execute the task after they are activated and the user applies an action Menus Terrain Preprocessing HMS Project Setup 2 Help Poet tet ET 1 58 969 137 Buttons Figure 6 1 MainView GUI with GeoHMS extensions features 40 95 Data Management Data that are introduced or derived with the program are being managed through role association For example when a DEM 15 introduced into the program GeoHMS will associate it with RawDEM which 15 the original DEM When a Fill command is issued the program will automatically offer the RawDEM as default for creating a depressionless DEM Asi
137. ogic analysis require a terrain model that is hydrologically corrected depressionless terrain model is used in the analysis The GIS analyzes the depressionless terrain model by applying the 8 point pour model where water flows across the landscape from cell to cell based on the direction of the greatest elevation gradient The process of analyzing the landscape characteristics and slopes for stream networks and subbasin boundaries is presented in Table 10 The steps in the analysis include filling depressions or pits calculating flow direction and flow accumulation delineating streams with an accumulation threshold stream definitions stream segmentation watershed delineation watershed polygon processing stream processing and watershed aggregation Depressionless DEM The depressionless DEM 15 created by filling the depressions or pits by increasing the elevation of the pit cells to the level of the surrounding terrain 1n order to determine flow directions The pits are often considered as errors in the DEM due to re sampling and interpolating the grid For example in a group of three by three cells 1f the center cell has the lowest elevation compared to its eight neighboring cells then the center cell s elevation will be increased equaling the next lowest cell Filling the depressions allows water to flow across the landscape This assumption 15 generally valid when a large event storm fills up the small depressions and
138. ommands produce different results The merge command will overwrite overlapping areas along the edges with the data that 15 merged last However the mosaic command will perform smoothing of data values along the overlapping areas Recognizing the different approaches for combining terrain 1s crucial to prevent abrupt artificial changes in elevation along the edges of tiles that will affect drainage path determination Other Zi Chapter 5 Data Assembly data assembly issues include combining various data sets of different resolution filling data gaps as shown in and data sampling techniques Data Gap l Data Gap Cd S Figure 5 1 DEM model with data gaps Contents errain Data Assembl Hydrologically Corrected and Depressionless Terrain Model Data Issues Hydrologic Coordinate System Specifications Terrain Data Assembly The assembly of quality terrain data for the study watershed consists of many important considerations Ultimately the quality of the results depends heavily on the terrain data Typically the continuous terrain data are assembled from joining tiles of terrain information as shown in Then data gaps are filled in with interpolated elevation values from neighboring elevation values to make a continuous DEM model as shown in However when terrain data are 28 Chapter 5 Data Assembly assembled in this typical manner they often contain errors and problematic areas fo
139. on Batch Points 1 and 2 appear to be relevant because they serve as basin outlets Keep these problems in mind and fix them in HMS if necessary These problems can also be fixed with some effort in HEC GeoHMS by editing various tables Currently the types of problems that can be easily fixed are reach and subbasin name revisions Checking VIP point BatchPoint1 End of checking UIP point BatchPoint1 PROBLEH the status could not be determined Checking YIP point BatchPoint 2 End of checking VIP point BatchPoint PROBLEH the status could not be determined Figure 9 13 HMS check data problems HEC HMS Basin Schematic The HMS basin schematic is the GIS representation of the hydrologic basin model with basin elements and their connectivity This step creates a point shapefile HMSPoint shp and a line shapefile HMsSConnect shp The HMSPoint shp contains point features such as subbasin icon locations outlets and junctions Subbasin icons are placed at the centroid of the area The HMSConnect shp contains line features such as subbasin connectors and reaches The subbasin connector joins a subbasin icon to the basin outlet Steps e Select HMS HMS Schematic e Review the input and output data sets as shown in Figure 9 14 Press OK 119 Chapter 9 Hydrologic Modeling System 22 HMS Schema Generation RwerShp SubBasin WateShdShp OOo VIPoints Amenivishp l wW shLen
140. ordinates as shown in Figure 9 19 Press OK Utility Reach Auto ame Basin Auko ame ta HMS Units HMS Check Data HMS Schematic HMMS Legend Add Coordinates Background Map File Lumped Basin Grid Cell Parameter File Distributed Basin Model Figure 9 19 Add Coordinates menu item The results are shown in Figure 9 20 and Figure 9 21 For a point feature in Figure 9 20 CanvasY Elevation columns describe an outlet in 3 dimensional space For a line feature in the coordinate pair FromCanvasX FromCanvas Y and CanvasX CanvasY describe a reach orientation with flow direction 2 Attributes of hmspoint 5hp Lue ME MEN A S 33100 00 Loi 49936 000 4 125325000 1391800 5 214615000 122535000 1824600 00 2151945000 124305 000 1256 900 00 48255 000 7122285 DDD 1516 500 1 15 8435 DD 125295 000 1451 200 BatchlFomnte 55s i 17 49935000 121395000 1411 800 Ur 151285000 123135 000 1177 800 L2 29903622 126433622 1487 000 8 126105 000 1545 200 oss i 45165000 124305 000 1821100 FUN 8 125610000 1509 500 i 9 3583 000 122175 000 3887200 ARAD toes 152545000 123925 000 1052 600 dE i 8 52455000 124680 000 145
141. own in Figure 7 19 75 Chapter 7 Basin Processing 76 DIE S Figure 7 19 Profile tool e Click on the stream segment on the map to get the profile as shown in Figure 7 20 2 Ele Cht For AmerRiv1 Grid values along the selected line River Shp Grade Break T T T 1000 2000 3000 4000 5000 6000 7000 8000 Figure 20 Stream profile The user has the capability to subdivide a basin based on grade break shown in Figure 7 20 Steps Select the Profile Subdivide tool when the stream profile chart 1s active and view the tool tip for directions as shown in mum Figure 21 Profile subdivide tool e Click on the chart approximately at the grade break as shown in Figure 7 22 Chapter 7 Basin Processing 2 Ele Cht For AmerHivi Grid values along the selected line River Shp 1000 2000 3000 4000 5000 2000 000 Figure 7 22 Stream profile with grade break e Watch the corresponding point that the user clicked as it blinks on the map display e Inspect the result and accept it Press Yes Corresponding point on the map that shows the grade break 22 Subdivide Basin and River 2 Subdivide basin and river the selected point Cancel E the default name for the outlet Press OK as shown in Figure 7 23 22 Basin and River Mame the point Caneel Figure 7 23 Default name for outlet T
142. p Generate Project Select the Original stream definition from the dropdown menu Press OK Verify the watershed outline boundary and press Yes Chapter 10 Example Application American River Basin 2 Project Manager Theme Frajsrea Proparea SHF Help Cancel e Verify the project area shapefile and then press OK 2 Workspace Generation amerrversprajamer been created e Note the workspace location and press OK Turn on the ProjArea shp theme to show the area extracted for an HMS model 2 Main iew No Active Project al 5 Projpnts shp e Outlet Heelgashp wzhedmg shp 5 5 ws hed grid strink grid strgrid facegrid fdirgrid Ss Basis AL fillarid 163 Chapter 10 Example Application American River Basin The pertinent data sets are extracted from the specified outlet location A ProjView named Amer is used for basin processing basin characteristics and HMS inputs Frajamer shp Outlet af River Shp iM fi WaterShd Shp _ Small amp tririd _ strink grid _ facegrid _ fdirgrid fillgrid The extracted data sets are smaller For example the extracted data for the fillgrid has 1308 rows and 2094 columns as compared to the original 2834 rows and 3662 columns The following window can be accessed by activating the Fil
143. p does not have any hydrologic significance The steps to aggregate watersheds are shown below Select Terrain Preprocessing gt Watershed Aggregation Confirm that the input of the River 15 River shp and Watershed 15 Wshedshp shp The output of the Aggregated Watershed is WshedMg shp a default name that can be overwritten by the user see Figure 6 24 Press OK Chapter 6 Terrain Preprocessing 22 Creating Premerged Watersheds River Hiver Watershed W shedshp Shp Aggreged watershed WshedMg shp Cancel Figure 6 24 Watershed aggregation operation The watershed aggregation operation results are shown in the WshedMg shp theme in Figure 6 25 2 Mainview al ws hed mg s hp _ Rivershp Wshedshp Shp wes hed grid strink grid strgrid facegrid fdirgrid fillgrid Amer Figure 6 25 Watershed Aggregation Operation Result Full Processing Setup When terrain processing 15 performed in batch mode Full Processing Setup is used The inputs are specified prior to processing and a list of default names 15 presented The full delineation accepts the depressionless DEM and derived drainage data set from it Therefore the DEM must be filled first to prepare for full delineation setup The inputs to the batch processing include the stream threshold for stream initiation The steps to perform full preprocessing are shown below 5
144. pe and press OK 3 Threshold for Outlet Definition Select the threshold type For outlet definition Area Distance Units Squared L ancel Enter the Area as 26 7 Threshold for Outlet Definition Enter area in distance units squared to define the outlet the largest drainage area is 92 5346 miles squared 26 Cancel The results of the search provide two possible points that do not exceed the specified area Using the Identify Area tool user finds that one possible point drains about 10 sq miles while the other point drains about 26 sq mi From this analysis the user understands that the downstream stream gage does not belong on the stream with 10 sq mi drainage area or stream from the confluence The applicable location of the downstream gage 15 on the stream with the 26 sq mi drainage area Confluence 36 sq mi Most Downstream Gage 26 sq mi per input gage location Chapter 6 Terrain Preprocessing The descriptions and procedures for useful tools are explained in Table 6 2 MainView Tools Descriptions and Procedures Tools Descriptions and Procedures Description This tool traces the flow path downstream of a user Flow Trace specified point Procedure To verify the drainage paths and watershed boundaries the user can apply the flow tracing tool and click on the display A flow path 1s drawn downstream as a graphic from the specified point Th
145. physical characteristics This chapter will discuss the tools for extracting topographic Basin Characteristics ae River Length characteristics of the watershed and NM river that are available 1n the ProjView GUI under the Basin Basin Centroid Characteristics menu Centroid Elevation Update Longest Flow Path Centroidal Flow Path The physical characteristics extracted for the streams and subbasins are summarized in Table 8 1 Contents Basin Centroid Longest Flow Path entroidal Flow Path 89 Chapter 9 Stream and Watershed Characteristics Table 8 1 Physical Characteristics of streams and subbasins Physical Characteristics Stream Length River Shp Upstream elevation Downstream elevation Stream Profile Watershed Area WaterShd shp Centroid Location Attribute Table Heading Riv_Length US Elv DS Elv Slp Endpt N A See Chart Area N A See WshCentroid shp Centroid Elevation Elevation Longest Flow Path Longest Flow Length Upstream elevation Downstream elevation Slope between endpoints Slope between 10 85 Centroidal Path N A See LongestFP shp Longest FL DSEIv Slp Endpt Slp 1085 N A See CentoidalFP shp Centroidal Length CentroidalFL The following sections illustrate the process outlined under the Basin Characteristics menu on the ProjView GUI to extract the stream and subbasin characteristics River Length 90 This step computes th
146. r The location of the project 15 important because subsequent derived data sets are stored relative to the project Chapter 10 Example Application American River Basin Theme Properties Theme M ame Ameriver_dem Source e ameriver amenive_dem Z 22O Cell ize 30 Rows 2834 Cals 3662 Left 1 105330 Right 4530 Bottom 563180 148200 Float Status Permanent Comments OF Cancel Locking 3 Perform drainage analysis by processing the terrain using the 8 point pour down approach A Fill Sinks e Select Terrain Preprocessing gt Fill Sinks Confirm that the input of the RawDEM also refer to as the unfilled DEM is AmerRiver dem The output of the HydroDEM is FillGrid FillGrid is a default name that can be overwritten by the user 2 DEM Filling Sinks Operations dem Help Cancel e Press OK This step takes about 45 minutes 149 Chapter 10 Example Application American River Basin af fillgrid 38 4 384 822 384 822 731 244 __ 731 244 1077 667 1077667 1424089 1424089 1770 511 BEI 1770511 2116 933 2116933 2463 356 2553356 2809 778 EN 22902778 3156 2 D ata _ Amerriver_dem 38 4 384 822 384 822 731 244 731 244 1077 667 1077667 1424 089 14
147. r computing drainage patterns from a hydrologic standpoint Often the terrain data undergo extensive editing to correct problematic areas Automated routines are available to fill depressions in the DEM The depressionless DEM may still not have streams located properly when compared to other map and photo resources Extensive editing 15 usually required to create a hydrologically corrected or conditioned DEM There are many issues surrounding terrain data assembly as discussed below Kiaenolia Magnolia Outlaw Plum en Oklah amin Splend Rose Moonshine Brookshire Katy Addicks Houston settegast 15749 Highlands Heights 5 City Richmond Park a Land wood City Figure 5 2 DEM tile quad names 29 Chapter 5 Data Assembly DEM Terrain Figure 5 3 Continuous DEM Hydrologically Corrected and Depressionless Terrain Model 30 The preparation of hydrologically corrected terrain data often requires much iteration through drainage path computations To represent the movement of water through the watershed the hydrologically corrected DEM must have the proper accuracy and resolution to capture details of the stream alignments and watershed divides Some of the problems arise when the watershed has low relief and the resolution 15 not fine enough to delineate the needed details Construction of a hydrologically corrected terrain model involves more complexity than combini
148. ration allowing the user to examine the result and giving the user options to accept or cancel the operation Rules e The subbasins must share a common confluence or e The subbasins must be adjacent in an upstream and downstream manner e More than two subbasins are permitted Steps e Make the WaterShp Shp theme active by pressing on the theme with the pointer tool The active theme appears raised e Use the select tool and select the two subbasins as shown in 2 1 al 1 5 D Outlet 4 WaterShd Shp Sm allS tr rid strink grid facegrid tdirgrid Figure 7 1 Basin merge Select the Basin Processing Basin Merge as shown in Figure Chapter 7 Basin Processing asin Processing Hiver Merge Hiver Protile Split Basim at Confluences Import Batch Points Delineate at Batch Points Figure 7 2 Basin merge menu item e The result of the merged subbasin is shown with a red outline Press Yes to accept the resulting merged subbasin or No to cancel the merge operation e In this case press Yes as shown in Figure 7 3 Merge Selected Basins e Confirm to merge displayed basins Figure 7 3 Basin merge confirmation The result of the merged basin 1s shown in Figure 7 4 2 Amernivl vil Amerriv1 shp e Outlet ri WaterShd Shp Smalls tra rid strink grid facegrid fdirgrid Figure 7 4 Basin merge result 67 Ch
149. rdinate system will be either Hydrologic Rainfall Analysis Project HRAP or Standard Hydrologic Grid SHG The data for a subbasin begins with the keyword Subbasin followed by a colon and the subbasin identifier One line beginning with the keyword Grid Cell follows for each cell in the subbasin Data for the subbasin ends with the keyword End Keywords are not case sensitive and may contain spaces Blank lines can be included and lines beginning with are ignored as comments The same grid cell file can be referenced by more than one subbasin allowing data for many subbasins to be stored in the same file The identifier for a subbasin must be exactly the same in the grid cell file as 1 is in the basin model Appendix Grid Cell Parameter File Format Table C I Parameter keyword definitions Keyword XCoord Y Coord TravelLength Area ScsCn SmaUnit Parameter Order End Subbasin Grid Grid Grid Grid Grid Grid Grid Grid End Cell Cell Cell Cell Cell Cell Cell Cell Subbasin Grid Grid Grid Cell Cell Cell Figure C 1 Definition x coordinate of the southwest corner of the cell y coordinate of the southwest corner of the cell travel time index from the cell to the subbasin outlet area of cell within the subbasin SCS curve number of the cell Soil moisture accounting unit name 85 Sample grid cell parameter file Units integer value integ
150. re 9 56 Control specifications time window HEC HMS Simulation An HMS run consists of basin meteorologic and control specifications components HEC 2000 as shown in Figure 9 57 With these three components completed HMS can compute flow The HMS parameter optimization capability can also be used with gridded models Refer to the HMS User s Manual for examples of gridded basin simulations HMS Project Definition Component Data View Tools Help Project Mame 5 Description 619 Application from 5 A Components Basin Model Meteorologic Model Control Specifications af m Control Feb 2000 Component Description Time related specifications for Feb 2000 storm 2 Click component for description double click to edit Figure 9 57 HMS components for simulation 144 Chapter 10 Example Application American River Basin CHAPTER 10 Overview Example Application American River Basin The purpose of this chapter 15 to illustrate the major steps the development a hydrologic model using GeoHMS The study watershed is the American River Basin tributary to Folsom Dam just east of sacramento California The watershed consists of 4 817 square kilometers 1 860 square miles The digital elevation model has been assembled to represent the watershed terrain In addition streamflow gages have been compiled into a data layer of gage locations names drain
151. reach then the user will need to merge both stream segments The capability to route the hydrograph through multiple reaches 1s supported in HMS The issue here 15 to raise awareness on modeling techniques options Steps e Activate the River Shp e Select the two stream segments with the Select tool e Select Basin Processing River Merge e The selected stream segments become one segment The reference point 15 not deleted Chapter 7 Basin Processing 2 1 Sm allStr rid No D ata strink grid facegrid fdirgrid fillgrid This reference point Select the separates the new and Select the existing stream existing streams new stream Figure 7 18 River merge River Profile The river profile tool provides information on slopes and grade breaks that can be used to delineate subbasins The river profile 1s created by extracting elevation values from the terrain model along the stream Creating the river profile can be performed in two ways River Profile menu item or the Qe Profile tool Method 1 River Profile menu item Steps e While in the ProjView document activate River Shp theme Select one or several contiguous stream segments shown Figure 1 18 with the Select tool e Select Basin Processing gt River Profile Method 2 Profile Tool e Activate the River Shp theme e Select the Profile tool and view the tool tip for directions as sh
152. referred to as SHG 2km SHG Ikm SHG 500m and so on The accompanying illustration shows cells in this map projection superimposed on the outline of the conterminous US note that for purposes of illustration the cells are larger than the 10 km maximum SHG cell M For identification each cell in the grid has a pair of integer indices 1 J indicating position by cell count of its southwest lower left or minimum x minimum y corner relative to the grid s origin at 96 W 23 N For example he southwest corner of cell 121 346 in the SHG 2km grid 15 located at an easting of 242000 m and a northing of 692000 m To find the indices of the cell in which a point 15 located find the point s easting and northing in the projected coordinate system defined above and calculate the indices with the following formulas 193 Appendix Standard Hydrologic Grid Specifications northin j floor 5 cellsize cellsize easting i floor Where floor x is the largest integer less than or equal to x Advantages Using the specified Albers equal area projection as the basis for the Standard Hydrologic Grid offers significant benefits The equal area property of the projection means that one inch of precipitation in any SHG 2km cell produces 82 acre feet of water The National Weather Service HRAP grid in contrast 1s based on a conformal map projection and cells sizes range
153. s WshedGrid see Figure 6 18 WshedGrid is a default name that can be overwritten by the user e Press OK 2 GRID Watershed Delineation FlowDirlarid Fdirarid Link tard strink arid W aterarid WES hed rid Cancel Figure 6 18 Watershed delineation operation 47 Chapter 6 Terrain Preprocessing 48 The watershed delineation operation results in 13 subbasins as shown in the WshedGrid theme in Figure 6 19 2 Main iew v ws hed grid strink grid stragrid facegrid fdirgrid fillgrid Amer meters Figure 6 19 Watershed delineation operation result Watershed Polygon Processing This step converts subbasins in the grid representation into a vector representation The steps to vectorize a grid based watershed are shown below e Select Terrain Preprocessing gt Watershed Polygon Processing e Confirm that the input of the WaterGrid is WshedGrid and the output of the Watershed 15 WshedShp shp see WshedShp shp is a default name that can be overwritten by the user e Press OK 2 Watershed Polygon Processing wW aterlarid wshedarid Watershed wW shedshp Shp Help Cancel Figure 6 20 Watershed polygon processing operation Chapter 6 Terrain Preprocessing The watershed polygon processing operation vectorized the grid based subbasin into polygon vectors as shown in the Wshedshp Shp theme
154. s II and FAR 52 227 19 or DFARS 252 227 7013 1 11 as applicable For purposes of the FAR the Products shall be deemed to be unpublished and licensed with disclosure prohibitions BY ACCEPTING TO CONTINUE OPERATION OF THIS SOFTWARE THE USER ACKNOWLEDGES ACCEPTANCE OF THIS LICENSE AGREEMENT AND EACH OF ITS TERMS AND CONDITIONS INDEX A Add Coordinates vii 111 122 123 182 B Background Map File 111 124 134 182 188 Basin AutoName vii 111 113 114 178 Basin Centroid vi 89 94 98 99 173 Basin Characteristics 16 19 89 90 92 99 104 105 108 172 173 175 176 Basin Merge 65 66 165 Basin Processing 3 12 16 18 65 66 74 75 79 85 146 164 165 170 Basin Schematic 111 119 186 Basin Subdivide 18 68 70 71 78 Basin Subdivision 65 68 70 72 Batch Point vi ix 18 80 81 82 83 84 85 88 119 133 135 Batch Subbasin Delineation 65 80 Bounding Box 95 C Centroidal Flow Path 89 107 108 176 Contour 16 Control Specifications Component 20 D Data Assembly 12 13 27 28 Data Check 111 117 Data Collection 12 21 DEM v vi 4 11 23 28 29 30 31 35 36 39 40 41 44 51 52 93 148 149 153 172 Depressionless 29 31 36 39 51 Depressionless DEM 36 39 51 Digital elevation model 11 Digital Line Graph 23 27 Digital Orthophoto Quarter Quads 24 Distance Units 44 45 153 Distributed Basin Model viii 111
155. sible SEM 1 wzhedmg shp Rmer zhp Wizhedzhp Shp ws hed grid strink grid strgrid facegrid fdirgrid fillgrid Kone SEES 4 Amerriver dem Use the tool and click on the grid cell with the identified gage The grid cell has 492 009 sq mi drainage area The result 119 area is 432 008 miles squared is shown in the lower left corner This cell has a drainage area that 1s adequately close to that of the gage Now analyze the watershed that 15 tributary to this grid cell Select HMS Project Setup gt Start New Project e Enter ProjAmer as the project name Press OK 2 Define a New Project Enter a new active project name mas 8 characters without spaces Pme Select and click on the cell to specify the outlet location 161 Chapter 10 Example Application American River Basin 2 MainViewl ActieeProject Proj amp mer Projpnts Outlet 162 1 wzhedmmg shp lt hp Wr 5 ws hed grid strink grid strgrid 9 fdirgrid fillgrid Amerriver dem Name the outlet point as Outlet Amer 2 Define a New Project Mame the outlet paint Outlet Amer Cancel Press OK Generate the Project 2 Lreate the study area select HMS Project Setu
156. sting stream and traces a new stream segment downstream from the specified point to the existing stream 2 Ameir Amercrivd hp MidP aint Outlet River Shp WaterShd Shp Sm allStr rid strink grid Zoom to facegrid this box _ fdirgrid Figure 7 11 New subbasin delineation 70 Chapter 7 Basin Processing e Zoom in to the area of interest and make the SmallStrGrid theme visible With the Basin Subdivide tool selected click on the point shown below Notice that the existing blue or dark stream does not exist in Figure 7 12 2 Amermivl Am erriv1 zhp MidP aint Outlet af River Shp 2 WW WisterShd Shp tr s rid 1 D ata _ strink grid _ facegrid _ fdirgrid I Figure 7 12 Zoom in prior to basin delineation e Accept the default name for the outlet and press OK as shown in Figure 7 13 2 Subdivide Basin and River Mame the point Figure 7 13 Default name of new outlet The result of the operation 15 shown in A new subbasin 15 created and a new blue or dark stream segment 1s also created from the specified point to the existing stream Where the two streams meet a point is created for reference information The existing and new stream segments are not joined together 71 Chapter 7 Basin Processing 2 1
157. subbasin is created with the outlet at the user specified point and a new stream segment is created from the user specified point to the existing stream Where the new stream segment met the existing stream a confluence 15 established by splitting the existing stream into two segments At the confluence there are two stream segments flowing in and one segment is flowing out The existing and new stream segments are not joined 2 AmerRirv1 Of x 4 Am hp New MidPoint Subbasin Outlet Rivershp Delineation 2 Shp SmallStr rid New Stream 1 No Data Segment strink grid _ facegrid fdirgrid Existing Stream Segment mW Figure 7 17 Subbasin delineation on a tributary result 73 Chapter 7 Basin Processing River Merge 74 When basin merges and subdivisions are performed stream segments are often created As an example the basin subdivision with method 2 created a stream segment that extends from the existing stream to the user specified basin outlet as shown in Figure 7 18 The point shown in the figure shows that the two segments are not joined together From a hydrologic perspective the two segments are considered as routing reaches If the user intends to model the routing with multiple reaches the user will need to develop routing parameters for both reaches However if the user intends to model the routing with a single
158. ted Basin Model A dd Coordinates Backeround Map File umped Basin Model rid Cell Parameter File Distributed Basin Model ydrologic Modeling System Connection 111 Chapter 9 Hydrologic Modeling System Reach AutoName This process names reaches in sequence from upstream to downstream The naming convention combines the letter R and a number For example the upstream reach starts with R10 and then R20 R30 R40 etc are the reach names proceeding downstream The intent of this tool is to quickly name the reaches the user can change the default names to something more descriptive Steps Select HMS gt River AutoName as shown in Reach A amp utaM ame Basin Auto ame ta HMS Units HMS Check Data 5 Schematic HMMS Legend Add Coordinates Background Map File Lumped Basin Model Grid Cell Parameter File Distributed Basin Model Figure 9 1 Reach autoname menu item e Press OK on the confirmation message box The Reach Autoname operation creates a Name column in the stream s attribute table as shown in 112 Chapter 9 Hydrologic Modeling System a T of Jae ew onse _ Amm 31838 1391 8000 3089 3088 5 0 0757 1411 8000 EE 8000 eee eee SEE EERE EEE EEC ELLE CELE L LLL LLL LLL LULL LLL
159. tep takes about 10 seconds Wzhedshp Shp E TES B ws hed grid strink grid strarid facegrid fdirgrid fillgrid Amerriver dem 157 Chapter 10 Example Application American River Basin H Stream Segment Processing 2 Main iew 5 hp 4 Weshedshp Shp 158 ws hed grid strink grid strgrid facegrid fdirgrid fillgrid dem Select Terrain Preprocessing Stream Segment Processing Confirm that the input of the LinkGrid 1s StrLnkGrid and FlowDirGrid is FDirGrid The output of the River is River River is a default name that can be overwritten by the user Press OK This step takes about 10 seconds Chapter 10 Example Application American River Basin I Watershed Aggregation Select Terrain Preprocessing Watershed Aggregation e Confirm that the input of the River is River shp and Watershed is Wshedshp shp The output of the AggregatedWatershed 15 WshedMg shp WshedMg shp is a default name that can be overwritten by the user Press OK This step takes about 30 seconds 2 Main iew al ws hedmg shp River shp zhedzshp Shp ws hed arid strink grid strarid facegrid fdirgrid fillgrid Ll LI E E E m l mmerriwer dem 159 Chapter 10 Example Application American River Basin 4 Extract pertinent spatial data and setup a hydrologic model In this step a watershed 15 def
160. ter 1 Introduction extension programs to perform spatial operations and develop additional parameters for populating the hydrologic model Intended Application of HEC GeoHMS HEC GeoHMS 15 intended to process watershed data after the initial compilation and preparation of terrain data 1s completed The assembly of GIS data can be performed using standard GIS software packages that support ARC Grid format Even though this user s manual provides some guidance and discussions on the proper approach for assembling data HEC GeoHMS is not intended as a tool for data assembly When assembling data it is important to understand how to use GIS software to put data of different types and formats into a common coordinate system A few examples of required data are a digital elevation model digital stream alignments and stream gage locations The most important data and often the most difficult 1s a hydrologically corrected digital elevation model DEM When the data assembly 1s complete HEC GeoHMS processes the terrain and spatial information to generate a number of hydrologic inputs It is intended that these hydrologic inputs provide the user with an initial HMS model The user can estimate hydrologic parameters from stream and watershed characteristics gaged precipitation and streamflow data In addition the user has full control in HMS to modify the hydrologic elements and their connectivity to more accurately represent field conditions
161. tics 3 Attributes of wshcentroid Shp Miel ES 2320000000 1657 4000 ce na ce Polygon 14752800 00 i2 4 Figure 8 36 Centroid elevation updated in the watershed attribute table Longest Flow Path The Longest Flow Path operation computes a number of basin physical characteristics the longest flow length upstream elevation downstream elevation slope between the endpoints and slope between 10 and 85 of the length These characteristics are stored in WaterShd shp theme Steps e Select Basin Characteristics gt Longest Flow Path as shown inFigure 8 37 The program will not prompt the user to verify the data input and output because that confirmation was already made before in 24 105 Chapter 9 Stream and Watershed Characteristics Basin Characteristics Hiver Length Hiver Slope Basin Centroid Centro Elevation Update Longest Flow Path Centroidal Flow Path Figure 8 37 Longest flow path menu item e Press OK to confirmation message box as shown in Figure 8 38 2 Longest Flow Path Computation 1 Longest fowpath computations successfully completed Figure 8 38 Longest flow path confirmation The result of the longest flow path operation is shown in Figure 8 39 2 AmerRiv vil lon gestfp Shp vil ws hcentroid S hp WaterShd Shp _ Batchpntshp E _ Elepointshp e F
162. traid wshceenroidShp O o HMS Ponk HM5SPaint HMSConnect HMSConnect Help Cancel Figure 9 14 HMS schematic input and output files Press OK at the confirmation message box The schematic with ArcView symbols is shown in Figure 9 15 2 AmerHivl hmsconnect Shp hms point Shp centroid Shp _ longestip Shp 9 5 i WaterShd Shp _ Batehpntshp _ Gage shp _ Elepointshp 1 _ Amerrivd shp oint Outlet Figure 9 15 Initial HMS schematic result The attribute tables of the HMSPoint shp and HMSConnect shp shapefiles are shown in Figure 9 16 Figure 9 17 The highlighted features are shown on the tables to display how the program uses the downstream element name Name in both tables to establish element connectivity 120 Chapter 9 Hydrologic Modeling System 2 Attributes of bi eee Shp a UL mE Oe Point io A RAD 0000 UserPoint2 555555 uu 2 Point io 140 LUUseiPont3 s Point 4 130 0 NM Point 5i 160 IserP ointh 2 Point 4 REg BatchPoint 15 4 Outlet Point 13 BatchPoint2 Figure 9 16 HMS schematic point attribute table 2 Attributes of hmsconnect Shp Le Amd 0 Vooms 2 JR120 FRRERSESEREREEEEESSSERENENERE mA n ae Polline 1 LI serPointe L
163. tributary of the HMS basin As multiple HMS Basin models can be produced from the same spatial database these models are managed through two shapefiles themes project points ProjPnts shp and project area ProjArea shp The management of these models shows the regions that already have a project In addition management of these models allows re creation of a study area with different thresholds or delete the project and related files easily and conveniently Start New Project To define a new project name and create a directory to contain extracted data and related files go to the HMS Project Setup menu HMS Project Setup Start Mew Project Generate Proyect New Threshold For Selected Project Remove Selected Project Select HMS Project Setup Start New Project Enter the project name as AmerRiv1 as shown in Figure 6 30 22 Define a New Project Enter a new active project name max 9 characters without spaces amp merRivi Cancel Figure 6 30 New project definition Select the S Specify Outlet Point tool e Specify the outlet point for a tributary basin model as shown in 59 Chapter 6 Terrain Preprocessing Figure 6 31 Specify outlet location Select HMS Project Setup gt Generate Project e Select the method of generating the project Select Original stream definition from the dropdown menu as shown in 32 The other two options are A new threshold and Hea
164. trol Specifications Delete Description EE Spplica impot Import Figure 9 37 Basin model import e Navigate to D hmsproj GeoHMS e Select and import the AmerRiv1 Basin Model e Press Import as shown in Figure 9 38 HHS Basin Model Import OW x Basin Model Ameri Description Directory d hmaprotGeoHMS_E 1 Basin model created with HEC GeoHMs Import Figure 9 38 HMS basin model import window The following errors shown in Figure 9 39 and Figure 9 40 warn the user that Batch Points 1 and 2 do not have a downstream element connection Press OK in both message boxes and make note to fix the downstream connections later with HMS HHS Critical Error Cannot link component downstream component does nat B atehP aint Figure 9 39 Critical error on batch point 2 133 Chapter 9 Hydrologic Modeling System 134 FW HHS Critical Error X Cannot link component downstream component does not exist BatchP ointl Figure 9 40 Critical error on batch point 1 Background Map File and Grid Cell Parameter File Specify the background map file and grid cell parameter file with the following steps Specify the background map file and grid cell parameter file by selecting File gt Basin Model Attributes menu item as shown in Figure 9 41 This produces the Basin Model Attributes screen shown in Figure 9 42
165. uns Using this basic framework a variety of models can be constructed employing different calculation methods and different assumptions and requiring different parameters Adopting a standard grid framework will enable hydrologists and water managers to exchange data and compare modeling results easily Standard Hydrologic Grid Definition The proposed SHG grid is a variable resolution square celled map grid defined for the conterminous United States The coordinate system of the grid 1s based on the Albers equal area map projection with the following parameters Units Meters Datum North American Datum 1983 NAD83 Ist Standard Parallel 29 degrees 30 minutes 0 seconds North 2nd Standard Parallel 45 degrees 30 minutes 0 seconds North 192 Appendix Standard Hydrologic Grid Specifications Central Meridian 96 degrees 0 minutes 0 seconds West Latitude of Origin 23 degrees 0 minutes 0 seconds North False Easting 0 0 False Northing 0 0 Users of the grid can select a resolution suitable for the scale and scope of the study for which it is being used For general purpose hydrologic modeling with NexRad radar precipitation data HEC recommends 2000 m cells and HEC computer programs that use the SHG for calculation will select this cell size as a default HEC will also support the following grid resolutions 10 000 m 5 000 m 1 000 m 500 m 200 m 100 m 50 m 20 m 10 m The grids resulting from the different resolutions will be
166. vossionnensseaudconseis soussensssnnstios suai snteasonseiusnemaenpsadensoertoeteesones 71 NEW SUBBASIN DELINEATION RESULT OENES T2 SUBBASIN DELINEATION ON A TRIBUTARY cscccsccssccscccsccscesccesccscenccesseussesccesscussesccesseeseesceesseuscs T2 DEFAULT NAME FOR OUTLET Fer REF RUE PEU resver 73 SUBBASIN DELINEATION ON TRIBUTARY RESULT 73 PROFLE SOUBDN IDE TOO RUE 76 STREAM PROFILE WITH GRADE BREAK cccesccsccsscecccscceccscceccscceccesceecescesscsscascescescessessesscscescescens ad DEFAULT NAME FOR OUTLET sawsscontscnsctensenienttsusnsesuestsneds sctucesebsbieedsiobadeseesnsende setuawsebebeacdenesauiucesensbes 77 BASIN SUBDIVISION FROM A PROFILE ccccseccssccscccsccssccuccesccscencceuccuscescsesccsseuccesccesceuseesccussenseuecs 78 SUBDIVIDE BASIN CONFLUENCES niicccesscocnsecosscessesccevenesssedssscesstenedssevsbosedpoveesssedeoosetssweedsvedevasess 79 SPLIT BASIN AT CONFLUENCES MENU ITEM cccccssccscccsccssccsccesccsceuccesccuscesccesceussesscescescesceusceuecs 79 BATCH POINT ATTRIBUTE 5 82 DELINEATE BATCH POINTS MENU ITEM 0ccsseccscccsccsccccsccsccssccscccsccsscccscescessccscsescessccessescessceecs
167. w GIS and Spatial Analyst Extension by Environmental Research Institute System Inc All Rights Reserved BY USING OR COPYING THIS SOFTWARE USER AGREES TO ABIDE BY THE COPYRIGHT LAW AND ALL OTHER APPLICABLE LAWS OF THE U S INCLUDING BUT NOT LIMITED TO EXPORT CONTROL LAWS AND THE TERMS OF THE FOLLOWING LICENSE AGREEMENT HYDROLOGIC ENGINEERING CENTER SHALL HAVE THE RIGHT TO TERMINATE THIS LICENSE IMMEDIATELY BY WRITTEN NOTICE UPON USER S BREACH OF OR NONCOMPLIANCE WITH ANY OF ITS TERMS USER MAY BE HELD LEGALLY RESPONSIBLE FOR ANY COPYRIGHT INFRINGEMENT THAT IS CAUSED OR ENCOURAGED BY Appendix Program License Agreement USER S FAILURE TO ABIDE BY THE TERMS OF THIS LICENSE License Agreement Hydrologic Engineering Center HEC grants to the user the rights to install HEC GeoHMS the Software either from a disk copy obtained from HEC a distributor or another user or by downloading it from a network and to use copy and or distribute copies of the Software to other users subject to the following terms and conditions copies of the Software received or reproduced by or for user pursuant to the authority of this License Agreement will be and remain the property of HEC User may reproduce and distribute the Software provided that the recipient agrees to the terms of this License Agreement No part of the Software may be exported or re exported in contravention of U S export laws or regulations THE SOFTWARE I
168. ydrologic Engineering Center HEC CPD 77 609 Second St Davis CA 95616 4687 9 SPONSORING MONITOGING AGENCY NAME S AND ADDRESS ES 10 SPONSORING MONITORING HQ U S Army Corps of Engineers AGENCY REPORT NUMBER 20 Massachusetts Ave NW Washington DC 20314 1000 11 SUPPLEMENTARY NOTES New document 12A DISTRIBUTION AVAILABILITY STATEMENT 12B DISTRIBUTION CODE Distribution is unlimited 13 ABSTRACT Maximum 200 words The Geospatial Hydrologic Modeling Extension HEC GeoHM S is a software package for use with the Arc View Geographic Information System GeoHMS uses ArcView and Spatial Analyst to develop a number of hydrologic modeling inputs Analyzing the digital terrain information HEC GeoHMS transforms the drainage paths and watershed boundaries into a hydrologic data structure that represents the watershed response to precipitation In addition to the hydrologic data structure capabilities include the development of grid based data for linear quasi distributed runoff transformation ModClark HEC HMS basin model physical watershed and stream characteristics and background map file GeoHMS provides an integrated work environment with data management and customized toolkit capabilities which includes a graphical user interface with menus tools and buttons The program features terrain preprocessing capabilities in both interactive and batch modes Additional interactive capabilities allow user to construct a hydrolo

Appendix 25 - HEC-GeoHMS 1.0 Software Documentation

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