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1. The two dimensional table is now complete We can use it in a calculation on the command line The calculation formula should have the following syntax Output map Two dim table Map1 Map2 Type the following formula on the command line of the main window Risk Risk Hazclas Vulclas J4 Press Enter The raster Map Definition dialogue box is opened Click OK Open the map Risk and check its contents Close the map window The creation of a risk map is not the final step in disaster management It is merely a tool which has to be used by decision makers in the planning process One of the politically important aspects is the percentage of each department with high medium or low risk These percentages will be calculated in this section Cross the maps Colombia and Risk andcreate across table Open the cross table and type the following formula on the command line Hight Lf f Risk High Npix 0 Also calculate the columns Medium and Low inthe same way Close the cross table and open the table Colombia Use join operation to read in the maximum value of the columns High Medium and Low ofthe cross table Use table join again to obtain the sum of the column Npix from the cross table Calculate the percentages of each department with high medium and low risk Find the five most endangered departments of Colombia the ones with highest percentage of their area classified as high risk A12 Resource Manual on Flas
2. a i To Core Bee a rege ee ad cic Ft ine ana e Select the control specifications when more than one has been created In this case the program will automatically select the control specifications as we only have one e Click Finish e You can create many simulation runs using different control specifications and meteorological models A Himalin Mn ePheees o coho Gpecmcoigngs Sekt one fg h al bek pa i Cancel Ca a es ee eee B Selecting components e Access the component editor from the Compute tab of Watershed Explorer e Select Simulation Run folder to expand it e Select the created simulation run Current 1 4 M rune TEE cusrent Crge Diaa faidi Hj Barudin ur Patio Start States Save states Manae Eire 1 Desoipion Pris Proj b Mint Shiba fro fa Dain Model Projhk A Meteorologi Hodek Jhi n it Conbrol Specifications Are 139 oe e Select the Ratio tab e Select No Ratio under Ratio Method dropdown menu A84 Resource Manual on Flash Flood Risk Management Module 2 If desired precipitation and flow ratios can be used for a simulation run If you do not use ratios the simulation results will be determined by the meteorological conditions specified in the meteorology model and the watershed physical properties specified in the basin model You can apply a ratio to the precipitation computed by the meteorological model before the precipitation is
3. chap071 1 Visualisation of the Data Before you can start with the actual analysis it is important to have an idea of the input data The following raster maps are available Colombia The departments of Colombia Landslid Regions with severe landslide problems Volcanic Regions with volcanic hazards Seismic Regions with seismic hazards Tsunami Regions with tsunami hazard seismically induced waves Inundat Regions with flood hazards Rivers Regions with torrential river activity Beach Regions with beach erosion and or accumulation Industry Main industrial regions Infraseg Main infrastructure Concentr Concentration of economic activities Topograp Topographic region of Colombia There is only one polygon map present Colombia The departmental boundaries of Colombia A1 Colombia You will first have to look at the maps before you start the analysis Double click the polygon map Colombia Now a Display Options dialogue box is shown in which you can modify how the map will be shown Select the check box Boundaries Only Accept all default settings and press OK The map is shown in a map window Drag the map window to the side of the screen Drag and drop the raster map Colombia into the map window The Display Options dialogue box is opened Click OK The raster map Colombia is now displayed together with the boundaries of the polygon map Click on several units in the map to find out their meaning Now look at
4. ol x oye 4 EE E CT n al ee BS ccm BS e WE BT E 01299 1136 0000 1078 0000 PE O s E LEE aie VE nonne 0 1515 _ 1073 0000 1050 0000 eee a a ONNE i i 0 1551 10730000 1050 0000 eee BF ected 2 ETEO le ADi 0 2000 1073 0000 1073 0000 45 47 1451 1450 5 0 0745 10500000 942 0000 Peererr ere rrr rrr rrerr errr rr rrr rere etree rer rrr rer rrr rerrrrrererrrrrr rr rerer rere errr rr rrr rrr rr rrr rr rrr rr rr errr rrr irre rer rrr rer rrr rerer rrr retire rererrrrrerrrrr errr rr rrr rrr rr rrr rr rrr rrr rrr rrr rrr rier errr rrr rer rrrrerrrrrererrrrre ttt trrrrrrriri rrr r trite C Basin centroid e Select Basin Characteristics Basin Centroid e Confirm the input and output in the operations e Click OK Dubhar miil Sh bead real E Sa thio acl witha ana Hei are e Select the Ellipse Method from the dropdown list e Click OK e Click OK again F Eerad Computation bten x peleci Method lo yae hed Cennad Congutation x Cura A new theme wshcentroid shp is created and added in the Proj View window The centroidal elevation is saved under the Elevation column in the watershd shp attributes table A48 Resource Manual on Flash Flood Risk Management Module 2 4 siina See maib Eii gee ae Tye _ hepi 4i eee D Longest flow path e Select Basin Characteristics Longest Flow Path e Confirm the input and output themes
5. 801 421 71 E a aaa eee T 40 eee or a 5536224 EEN Ton i EEE EET EEE Eee Eee TEE Teeter reer eer ee eee eee eee TTL E EET RTE TE CETTE ETE TTT ELEC LEE EEE rs ETE ETT ETE Tete EET eee EE RELI eer ieee ett titi tiet et eee eee Field ocn shows the average curve number for each sub basin 5 2 Time of concentration A Two year rainfall e Add the 2 year 24 hour precipitation intensity grid Rinten_inch as a grid theme in the project view e Select Hydrologic Parameters Rainfall 2 Year e Click OK e Confirm the input and output themes as shown below e Click OK e Click OK again Annexes A51 Subia Maani Shen Plat aria Anton rm We eria a redirect bg Uke Hrg Careri The result of the computation will be saved in the attributes table of watershd shp B TR55 flow path segments Select Hydrologic Parameters TR55 Flow Path Segments Confirm the input and output themes as shown below Swab aur aunt es thal aP TAT hira cenidedatn bhi Limajt ersen Sho Fliveticciad F spod Fia Picadas Plow esk Poets Click OK Click OK again C TR55 flow segment parameters Select Hydrologic Parameters TR55 Flow Segment Parameters Click OK The function will compute and update the fields ChSlp channel slope ChLength length Shslp slope for the TR55 shallow flow overland flow ConShLength length of TR 55 concentrated shallow flow segment
6. A Reach auto name e Select HMS Reach Auto Name e Click OK e The reach auto name creates a Name column in the River shp attributes table as shown in the table below B Basin auto name e Select HMS Basin Auto Name e Click OK This also creates a Name column in the sub basin s watershed shp attributes table Annexes A53 C Map to HMS units e Select HMS Map to HMS units e Select SI Unit from dropdown menu e Click OK e Click OK again e The results of the unit conversion are three columns added to the river s attributes table and six columns added to the sub basin s attributes table The added columns contain the ending HMS t o Aeh T E E EAA samo Bason razo 158 200 mzoa maw a0 10780000 ra r 1o05 105 7 iraco orama e 70 000 F Sa 000 RAPD 7a 40 ETA ETE ne Fee ea ers EA SGT RA eR Sem t S as es mem ma m a Sa aaa ona Oe es eo or Tow naa ed LEAD Enj Wiar S FaLa Fi Dra mTT a 15 Sa ion ain 72 on aj ari disi E Oasis ari T SN Tie m i Esaf 14 D HMS check data e Select HMS HMS Check Data e Verify the input data sets as below Hra Eem Shp SubH asin punter thal Sbr a WPorls rope gs Wiehie PnP Shei E e Click OK e Make a note of the filename and its location Click OK again A54 Resource
7. Basin processing 4 1 Revise sub basin delineation 4 2 Basin characteristics 5 Estimation of hydrological parameters and HMS inputs 5 1 Sub basin curve number 5 2 Time of concentration 5 3 Develop HMS inputs ran ll Working with HEC HMS Getting started with HEC HMS 1 1 HEC HMS overview 1 2 Setup an HEC HMS model with inputs from HEC GeoHMS 2 Control specifications 3 Entering shared component data 3 1 Creating and entering time series data 4 Creating a meteorological model 4 1 Inverse distance method 5 Defining models and parameter values for hydrological elements 5 1 Program options 5 2 Selecting methods and assigning parameters to hydrological elements 6 Hydrological simulation 6 1 Simulation run 6 2 Viewing results for the current run 6 3 Optimisation trial 6 3 1 Creating a new trial 6 3 2 Viewing the trial results Annexes A25 A26 A28 A29 A30 A33 A33 A34 A41 A44 A44 A47 A51 A51 A51 A53 A58 A59 A59 A62 A67 A68 A68 A73 A73 A76 A79 A79 A83 A83 A85 A89 A89 A93 A27 Working with HEC GeoHMS A28 Resource Manual on Flash Flood Risk Management Module 2 1 Open Arc View and load HEC GeoHMS e Open Arc View and create a new project as a Blank Project e Select File Extensions menu item e Inthe Extensions dialogue that appears scroll down to HEC GeoHMS 1 1 e Check the box next to it to turn it on e Click OK T Ertensiona i h F renr
8. Click OK Annexes A41 FR Define a New Project x Enter a new active project name OK mas 8 characters without spaces Pro hH Cancel e Anew theme name projpnts shp will be added to the Main View e Select Bland click on the cell to specify the outlet location bo a a dsi j ai en i mana es a ei fo oc cy som o ff r ne ae ie 54 a es e Name the outlet point as Outlet _A e Click OK Define a New Projec x Click on this cell Name the outlet point Outlet A Cancel e Select HMS Project Setup Generate Project e Select Original stream definition from the dropdown menu e Click OK Generate the New Project Construct the basic study area based orr Original stream definition Cancel e Verify the watershed outline boundary and click Yes Generate the New Project 3 Create the study area es A42 Resource Manual on Flash Flood Risk Management Module 2 e Verify that the project area shape file name is ProjArea shp and click OK Enter OK Enter new project description EE SS Cancel Dieter Gestion x Cyathea aids ne EL Note the workspace location and click OK e Turn on the ProjArea shp theme to show the area extracted for the HMS model rill abe di ima phe Dyk ffi Hia begana f ated one Bede ite y Wahacubho Son e
9. Genenste to Shane will i Geena nie Pe Geshouler ard hened Ori ___Carend Dad nak E shere Fer 1 7 p Lil it Heed hers M Hae De HE Comes i bade ire are Spal Analy caa lo peen cate bor KEL RMS Vaer 1 1 Conducted an Wied dan Zt ore oo HEC GeoHMS will automatically load the Spatial Analyst extension HEC GeoHMS will create two document types MainView and ProjView in addition to Arc View standard document as shown below Annexes A29 2 Graphics user interface with HEC GeoHMS extensions 2 1 MainView The MainView document is generally responsible for terrain preprocessing and spatial database setup discussed in detail in this section The following screenshot and tables show the menus buttons and tools added by HEC GeoHMS when the MainView document is active i iene G6 128 ch ad YE Dee Se Table 1 MainView Menus The Terrain Preprocessing menu is used to modify process and analyse the terrain It can process the terrain in two ways step by step or by batch It also has a data management capability for tracking data sets as they are derived After the terrain has been processed the HMS Project Setup menu is used to extract the processed terrain information from the MainView The extracted information will be placed in a separate view called the ProjView There are several options for the extraction of terrain information detailed description presented later The Utility menu conta
10. It includes summary information such as the basin model meteorological model and control specifications used in the underlying simulation run It indicates which objective function method was used the start and end of the evaluation period for the function and the final value of the function when the search method finished In gives the volume peak flow time of peak flow and time to the centre of mass of the computed and observed hydrographs Finally it provides volume and peak flow differences between the computed and observed hydrographs e Select the Results tab in Watershed Explorer e Select Optimization Trial folder and Trial 1 EEA TT Objective Function Rea ri ar f Di erR Project Muyuni Optimieshen Trial Trial L ais Sart of frig Sedan frre ea Benin Habt Penk Diiia Function Emig Tria SMbun bie 05 30 Mebeurokege Medel Jhu fr De a iaka Reid Compute Tree Geico 13 7 Corina Snecticasons June 1 ily Mydroaragh Capii Object Function at Ean Eemmeri Cater AL Ir Fess Tomparson Start of Puncton s diab ie Types aimee Error m E Crd of furtm Sum bes fehl ish i il itea Firriir Oit Voua lirie a Hri pipea SOFE are Ltn Chaat aed Ofensa Pareri La biii N E Pes re sree a Gage orea ME 61 40 2 15 a 17 72 ks Diii Peak Pos ENS 16 5 B 5 ag F1 L pon Tire of Fei oin y W fund Fa Oc E SiB Time of Center of Mia inl 3 Te ffl 34 eat ba iE ob pm e Select Objectiv
11. Manual on Flash Flood Risk Management Module 2 The dhucishtahen check he GhiniGonal hi be hoc been camia i 0 Wd hoi ge Prank Re The output file SkelConsChk txt contains the results of the check results The end portion of the file is shown below CHECKING SUMMARY Unique names no problems River Containment no problems center Containment no problems i River Connectivity no problems VIP Relevance no problems 3 d i I E HMS schematic e Select HMS HMS Schematic e Verify the input and output data sets as shown below e Click OK e Click OK again e The HMs schematic with Arc View symbol is shown in the figure below Annexes A55 F HMS legend e Select HMS HMS Legend The output of HMS legend is shown below ta E E EO Geti G Add coordinates This step attaches geographic coordinates to the hydrological elements in the attributes tables of HMSPoint shp and HMSConnect shp e Select HMS Add Coordinates e Click OK H Background map file The background map file is the output of the background map of sub basin boundaries and stream segments from HEC GeoHMS to HEC HMS e Select HMS Background Map File e Make a note of the file name and location and click OK z Rae ree E in ae Le ee VES vie FHE Creation r bree Le et eS ee EE E ia en ieee y a inne The map file Prolhk map has be
12. Options dialogue box and click OK The raster map Colombia is now replaced by the raster map Seismic Select the menu options File Create Create Table Enter the following filename Seismic Select the domain Seismic and click on OK A domain in ILWIS determines the content of a map or a table If we have classes the domain is a list of the possible names of the classes A table which will be linked to a map should therefore have the same domain The table is now shown You see the domain items in the grey column on the left hand side Select Columns Add Column Enter the column name Weight and select the domain Value Enter the values 0 and 10 for the value range and 1 0 for the precision Click OK Fill in the weights of the three classes as indicated in the table on the previous page Close the table Now you have made a table with weight values for the map Seismic es e Repeat the same procedure for the maps Landslid Volcanic Tsunami and Beach Create a table for each map using its own domain Before you can go on to the next step you still have to indicate that the tables should be linked to the maps This is done by changing the properties of a map Right click the mouse button on the map Seismic and select from the context sensitive menu the option Properties Now a dialogue box appears in which the properties of the map are shown such as the domain the number of pixels etc Click on the option Attribut
13. Risk Management Module 2 oa P amp S nmanmnanrw 2 Annex f TTA a l Zz i iE EWA GS Guiding Principles for Effective Early Warning United Nations International Decade for Natural Disaster Reduction IDNDR Early Warning Programme By the Convenors of the International Expert Groups on Early Warning of the Secretariat of the International Decade for Natural Disaster Reduction IDNDR 1990 2000 Bui a Culhoe of Pare IDNDR Secretariat Geneva October 1997 Annexes A19 The Objective The objective of early warning is to empower individuals and communities threatened by natural or similar hazards to act in sufficient time and in an appropriate manner so as to reduce the possibility of personal injury loss of life and damage to property or nearby and fragile environments Risk Assessment Risk assessment provides the basis for an effective warning system at any level of responsibility It identifies potential threats from hazards and establishes the degree of local exposure or vulnerability to hazardous conditions This knowledge is essential for policy decisions which translate warning information into effective preventive action Several groups must contribute to this empowerment Each has a set of essential overlapping functions for which it should be responsible Members of vulnerable populations should be aware of the hazards and the related effects to which they are exposed and be able to take specific action to
14. To be applied effectively warnings need to be clearly understood and operationally relevant to local agencies which are more frequently oriented toward non specific hazard functions Early warning systems must be based upon risk analysis which includes the assessment of the occurrence of hazards the nature of their effects and prevailing types of vulnerability at national and local levels of responsibility The warning process must lead to demonsirated practices that can communicate warning and advisory information to vulnerable groups of people so that they may take appropriate actions to mitigating loss and damage Locally predominant hazard types and patterns including small scale or localised hydrometeorological hazards related to patterns of human economic or environmental exploitation must be incorporated if early warning is to be relevant to risk reduction practices There is a continuing need to monitor and forecast changes in vulnerability patterns particularly at local levels such as sudden increases in vulnerability resulting from social developments These may include conditions of rapid urbanisation abrupt migration economic changes nearby civil conflict or similar elements which alter the social economic or environmental conditions of an area The primary responsibilities must rest at local levels of involvement for producing detailed information on risks acting on the basis of warnings communicating warnings
15. cee le R460 ce R470 pay RAPOWS50 Meteorologic Models Control Specifications Time Series Data Basin Name Projhk Element Name R450 Description Downstream JR470 Routing Method None LossfGain Method Mone A82 ENKE EI To hg Resource Manual on Flash Flood Risk Management Module 2 6 Hydrological simulation 6 1 Simulation run A Creating a simulation run e Select Compute Create Simulation Run e Enter any name to the simulation run e g Current 1 e Click Next gt Create a Simulation Run Step 1 of 4 Es A simulation run must have a name You can give ita description after it has been created Mame Current To continue enter a name and click Mext Back Mest Cancel e Select the basin model when more than one basin model has been created In this case the program will automatically select the basin model as we only have one e Click Next gt Create a Simulation Run Step 2 of 4 4 A Simulation run includes a basin model Select one from the list below Name Description Projhk Basin model created with HEC GeoHMs v1 1 Beta a To continue select a basin model and click Next lt Back Next gt Cancel e Select the desired meteorological model when more than one meteorological model has been created In this case the program will automatically select the meteorological model as we only have one e Click Next gt Annexes A83
16. dammed lakes hanging glacier in contact with the lake bigger glacier area fast retreating debris cover at glacier tongue area steep gradient at glacier tongue area presence of crevasses and ponds at glacier tongue area toppling collapses of glacier masses at the glacier tongue ice blocks draining to lake hanging glacier in contact with the lake Physical conditions of surroundings Besides moraines mother glaciers and lake conditions other physical conditions of the surrounding area as given below may also cause the lake to be dangerous e potential rockfall slide mass movements site around the lake which can fall into the lake suddenly e large snow avalanches around the lake which can fall into the lake suddenly neo tectonic and earthquake activities around or near the lake area A108 Resource Manual on Flash Flood Risk Management Module 2 e climatic conditions in which a relatively wet and cold year is followed by a hot and wet or hot and arid year e very recent moraines damming the lake at the tributary glaciers that used to be just a part of a former complex of valley glacier middle moraines as a result of the fast retreat of a complex mother valley glacier e g Lunana area in Pho Chu Basin in Bhutan e sudden advance of a glacier towards the lower tributary or mother glacier having a well developed lake at its tongue Annexes A109 Part 3 Examples of Some Generalised Calculations and Syntaxes Using ILWIS Sof
17. e Click OK e Click OK again Sian Annexes A49 A new theme Longestfp shp will be added to the Project The longest flow path computation also stores the physical parameters in the watershed s attributes table bye ee y Tei re E yi Bam y E i pirn a Syed ff Bice Bee i oem Gs hee Co j ee eae i gem af gra E Centroidal flow path e Select Basin Characteristics Centroidal Flow Path e Confirm the input and output themes A50 Resource Manual on Flash Flood Risk Management Module 2 5 Estimation of hydrological parameters and HMS inputs 5 1 Sub basin curve number e Add cn_grid as CNGrid theme in the project view e Select Hydrologic Parameters Subbasin Curve Number e Select watershd shp as sub basin theme and cn_grid as CNGrid theme from the dropdown menus as shown below T Ciuk bhiin Curve furbir fer debbie X Subllsain tasha She CHine Cr ord l He Corer al e Click OK Ei Subbasin GRID Curve Number Operates x i DH Hik heir c hk rk LH ce e Note the location of the result dbf file and click OK e The resulted average lumped curve number for each sub basin is also saved in the attributes of watershed shp iL Attributes of watershd Shp B x 8560 000000 978 0000 ee 0 138 2572203 1258 823 71 7680 000000 1322 0000 n S 0258 2597 056 1423 949 71 4520 000000 1229 0000 0 266 0 277 1532 548
18. glaciers and glacial lakes has been systematically carried out for the drainage basins on the basis of topographic maps and satellite images similar to the methodology carried out for Nepal Bhutan and other river basins in the Hindu Kush Himalayan region The following sections describe how the inventories for both the glaciers and glacial lakes were carried out Inventory of Glaciers The glacier margins are delineated in the geo referenced Landsat 7etm of panchromatic mode and compared with other individual bands as well as in different colour composite bands and the exact boundaries between glaciers and seasonal snow cover determined The coding system is based on the subordinate relation and direction of river progression according to the World Glacier Inventory The descriptions of attributes for the inventory of glaciers are given below Numbering of glaciers The lettering and numbering start from the mouth of the major stream and proceed clockwise around the basin through each and every small tributary Registration of snow and ice masses All perennial snow and ice masses are registered in the inventory of glaciers Measurements of glacier dimensions are made with respect to the carefully delineated drainage area for each ice stream Tributaries are included in the main streams when they are not differentiated from one another If no flow takes place between separate parts of a continuous ice mass they are treated as separate uni
19. in the histogram On the basis of these values we can make a subdivision in hazard classes Close the graph and the histogram table From the range of values you can see that the best way to classify the map hazard is to divide it into classes of 5 units Annexes A7 In the Main window select the following menu items Operations Statistics Histogram In the Main window select File Create Create Domain Create a new domain Hazclas Select the options Class and Group Click OK The Domain Editor is opened Select Edit Add Item and fill in the following classes Boundary Class 5 Very low hazard 10 Low hazard 15 Moderately low hazard 20 Moderate hazard 25 High hazard 100 Very high hazard Close the Domain Editor In the Main window select Operations Image Processing Slicing Select the raster map Hazard and give Hazclas as the output raster map Use the domain Hazclas Click OK Open the representation of Hazclas and edit the colours so that Very low is green and Very high is red with intermediate changes Display the map Hazclas Use the Pixelinfo to check the result Create annotation for the map Hazclass grid scale bar title legend and save the result as a map view with the name Hazclas Close the Map window and the Pixel Information window This ends the first exercise in the creation of a hazard map In the next exercise you will create a vulnerability map 3 Creating a Vulner
20. of the corresponding glacier registered This index only refers to end moraine dammed lakes because only they are related to their originating glaciers As not enough field data exist the average depth of glacial lakes is difficult to establish in most cases Based on field data and as an indication only the average depth of a glacial lake formed by different causes can be roughly estimated as follows cirque lake 10m lateral moraine lake 20m trough valley lake 25m end moraine lake 30m blocking lake 40m glacier erosion lake 40m The water reserves of different types of glacial lakes can be obtained by multiplying their average depth by their area A106 Resource Manual on Flash Flood Risk Management Module 2 Part 2 Potentially Dangerous Glacial Lakes On the basis of actively retreating glaciers and other criteria the potentially dangerous glacial lakes were identified using the spatial and attribute database complemented by multi temporal remote sensing data sets Medium to large scale aerial photographs were used for detailed geomorphic studies and evaluation of the active glaciers and potentially dangerous lakes In general based on geomorphological characteristics glacial lakes can be grouped into three types glacial erosion lakes glacial cirque lakes and moraine dammed lakes The former two types occupy the lowlands or emptying cirques eroded by ancient glaciers These lakes are located more or less away from pre
21. outlet of the major stream and proceeds clockwise around the basin Longitude and latitude Reference longitude and latitude are designated for the approximate centre of the glacial lake by creating a digital point map over the screen digitised glacial lakes Area The area of the glacial lake is determined from the digital database of the lake after polygonising the lake s segment with unique identity Length The length is measured along the long axis of the lake and represented in metres Width The width is normally calculated by dividing the area by the length of the lake down to one decimal place in kilometre units 0 1 km Depth The depth is measured along the axis of the cross section of the lake On the basis of the depth along the cross section the average depth and maximum depth are estimated The data are collected from the literature if available Orientation The drainage direction of the glacial lake is specified as one of eight cardinal directions N NE E SE S SW W and NW For a closed glacial lake the orientation is specified according to the direction of its longer axis Altitude The altitude is registered by the water surface level of the lake in masl Classification of lakes Glacial lakes can be classified as follows e glacial erosion lakes including cirque lakes trough valley lakes and erosion lakes e moraine dammed lakes also divided into neo end moraine and paleo end moraine lakes including e
22. the maps that contain information on the different types of hazards in Colombia Drag and drop the map Seismic into the map window Accept the defaults in the Display Options dialogue box and click OK The raster map Colombia Is now replaced by the raster map Seismic Check the meaning of the mapping units Evaluate the other maps Landslid Volcanic Tsunami Inundat Rivers Beach and Topograp with the same procedure Open the pixel information and drag and drop the maps Colombia Seismic Landslid Volcanic Tsunami Inundat Rivers Beach and Topograp to it Check the combined information of the maps while you move the mouse pointer through the map window A2 Resource Manual on Flash Flood Risk Management Module 2 Display the Options dialogue box and click OK The raster map Colombia is now replaced by the raster map Seismic Check the meaning of the mapping units Evaluate the other maps Industry Infraseg and Concentr by dragging and dropping them in the map window Check their contents Add these maps to the pixel information window Check the combined information of the maps while you move the mouse pointer through the map window Close the map window and the pixel information window Also have a look at the maps used for the vulnerability analysis When you have a sufficient idea of the input data you can continue with the next topic 2 Creating the Hazard Map In this exercise you will look at the first as
23. 9 Available method and data requirements for models for different hydrological elements in HEC HMS Element vaii Model method Data required Deficit amp Initial deficit maximum storage constant ratio constant loss impervious area Exponential Initial range initial coefficient coefficient ratio loss exponent impervious area Green amp ampt Initial loss moisture deficit suction conductivity mm loss hr impervious area Initial deficit grid maximum storage grid constant rate Gridded deficit grid initial deficit grid ratio impervious grid maximum constant loss storage grid ratio constant rate grid ratio impervious grid ratio uated Curve number grid initial abstraction ratio retention curve number scale factor loss Initial canopy canopy storage grid initial surface Loss MORER surface storage grid maximum infiltration grid initial moisture i oe deal soil soil storage grid initial groundwater percent accounting l ii storage grid coefficient grid Initial constant Initial loss infiltration constant infiltration rate mm hr and loss impervious area SCS curve Initial abstraction optional curve number impervious number loss area Initial water content residual content saturated content Sub basin Smith parlange bubbling pressure pore distribution conductivity mm loss hr impervious area temperature gauge beta 0 Celsius canopy storage surface depression storage Soil
24. Annex 1 Hazard Vulnerability and Risk Analysis This exercise and accompanying data were made available by CJ van Westen Department of Earth Resources Surveys International Institute for Aerospace Survey and Earth Sciences ITC PO Box 6 7500 AA Enschede The Netherlands Tel 31 53 4874263 Fax 31 53 4874336 e mail WESTEN ITC NL Summary This case study is intended to illustrate the meaning of hazard vulnerability and risk using a very simple data set on the national scale of Colombia South America The occurrence of a disaster depends on two factors e Hazard The probability of occurrence of a potentially damaging phenomenon e Vulnerability The degree of loss resulting from the occurrence of the phenomenon First a qualitative hazard map is generated by combining several factor maps Then a vulnerability map is made The hazard and the vulnerability maps are combined into a risk map Getting started The data for this case study are stored in the accompanying folder If you have already installed the data on your hard disk you should start up ILWIS and change to the subdirectory where the data files for this exercise are stored If you have not installed the data for this case study yet please run the ILWIS installation program see ILWIS Installation Guide Double click the ILWIS program icon in the ILWIS program group Change the working drive and the working directory until you are in the data directory e g c
25. E F ET F i T F m m F D a Bo i5 Fi ad 5 G Optimisation and parameter estimation Optimisation and parameter estimation searches for the best parameter values for the model The systematic search for the best optimal parameter values follows the procedure shown in the following figure Annexes Compare the computed and observed parameters If the computed model parameter is not satisfactory then A96 Note down the derived optimised parameter values from the Optimised Parameter table see above Create a new trial or update with derived optimised parameters in the previous trial Run the trial Again compare computed and observed results using the optimised parameters and simulate the process until you find the best parameter values to model Resource Manual on Flash Flood Risk Management Module 2 Annex 6 Inventory of Glaciers and Glacial Lakes and Identification of Potentially Dangerous Glacial Lakes This Annex is an extract of an unpublished manual titled Spatial Data Input Attribute Data Handling and Image Processing of Rolwaling Valley Nepal prepared by P K Mool and S R Bajracharya ICIMOD The Annex has three parts The first includes the methodology for preparing the inventory of glaciers and glacial lakes focusing on the attributes of glaciers and glacial lakes important for identifying potentially dangerous lakes The second part deals with the criteria for identifying potentially dan
26. Hi HEC GeoHMs This tool draws contours mt thee user specified point b am 2 2 ProjView The ProjView document is generally responsible for hydrological processing hydrological model construction and setup discussed in detail in this section Basin processing extraction of stream and watershed characteristics extraction of hydrological parameters and HEC HMS setup are the major actions performed in the ProjView document The Screenshot and Tables 4 6 show the menus buttons and tools added by HEC GeoHMS when the Proj View document is active Bani OB a a E Toma he pee TA r TEAK Buttons Annexes A31 Table 4 ProjView Menus Menu Description S O Huskyn Lunge Fawr Aerial 2 Vax Deng Aana TASS Fleer Path berani TASS Esperi Tt Pat aeushess to E ace Baan Siope Bair Adii arte hiap to HMS Limia He Check Daia MMS chama Shireen HMS Process Back oround Hap Fie Dumpad Basn Hode Gaj Lei Pigeon Fie Dipi Thana Tagi Te View There Tg Flamer d Therma Tag Fey Danaya H Thare Genese LUAT Gad CH ran Sahetes Yes bo ina Shaded DEM to Image A32 This menu provides interactive and batch processing capabilities to modify existing sub basins and delineate new sub basins In the interactive mode the tools allow the user to see the delineation results assess outcomes and accept or deny the resulting delineation In the basin mode the user can supply the outlet locations and the prog
27. IN 15 565 e Select the Options tab e Select Outlet for R420W420 sub basin under Observed Flow and Observed Stage from the dropdown menus e You may enter the reference flow value and reference flow label under Ref Flow M3 S and Ref Label if they are available The reference flow can be any significant flow value such as bank full discharge flood watch or levee overtopping It can be specified to assist in interpreting computed flow results e Define the Loss and Transform methods and enter the values of the SCS curve number and lag time value for other sub basins of the model in the same way e The sample parameter data for the other sub basins is shown in Table 10 you can also see it in the attributes table of watershd shp Sy Subbasin Options Basin Name Projhk Element Name R4270W470 Observed Flow Outlet Observed Stage MMES Eleyv Discharge Mone Ref Flow Mas Ref Label Ge de Table 10 Sample basin parameters SCS Curve number Observed flow Observed stage B Junction The junction element does not have any special data or properties only observed flow and stage data are needed to define the junctions that have those time series data In this case junction Gage 7 junction Gage 8 and junction Outlet_A only have the observed stage or observed flow gage station for Gage 7 Gage 8 and Outlet respectively e In W
28. Select the Time Series Gage in component editor e Select Data Source as Manual Entry Units as Incremental millimeters and Time Interval 30 Minutes from the dropdown lists and enter the latitude and longitude of the precipitation gauge location as shown below Components Compute Penu Se S Qh Time Series Gage Time Wirde Table Graph Mare Cage B Deescription Hamghbbem E Data Source Mirna trtry Unis Incremental Miilmeters Teves Iribervial 30 Mira sliew Lahi Dapa O Lettie Fiia 20 Laius Second 45 Lovage Depod So Lovage Mta 27 Longhe Senor 5A Latitude Longitude e Select Time Window e Enter the start date start time end date and end time Conperents Compute Pepas i imedens Gage Tran Window Tabie Graph Parra Hampe THI Start Cabe AE yl aoe Stat Tire Hia 09 30 Freel Dabe Ade eee Ered Tere HH mm eo A70 Resource Manual on Flash Flood Risk Management Module 2 e Select Table Copy the data from the Excel file and paste i Time Series Gage Tabie Time fd heey HH mm Precipitation MM inc Similarly enter the data for the other gauge stations B Water discharge Create the gauges Gage 07 Gage 08 and Outlet for water discharge data in the same way as for precipitation Input the time series gauge information define the time window and input the table data as described above
29. Some of the different precipitation methods available for describing meteorology are shown below Table 8 together with the parameters and data required In this example we use the inverse distance precipitation method to describe the meteorological model Table 8 Precipitation methods available for describing the meteorological model Precipitation o Frequency storm Used to develop a precipitation event in which depths for various durations within the storm have a consistent excedence probability Gauge weight User specified weights applied to Gauge depth weight time weight precipitation gauges total depth index mm Gridded precipitation Allows the use of gridded precipitation oe a on products such as NEXRAD radar Peep ANON EGALA Inverse distance Calculates sub basin average precipitation by applying an inverse distance squared weighting with gauges Intensity duration storm duration storm area precipitation depth value for the whole storm duration Latitude longitude value of precipitation stations and node point for each sub basin SCS storm Applies a user specified SCS time distribution to a 24 hour total storm depth Specified Applies a user defined hyetograph to a Precipitation gauge within or hyetograph specified sub basin element nearest to each sub basin Standard project Uses a time distribution to an index a Seats Transposition factor storm precipitation depth 4 1 Inverse distance method D
30. a el yi impa ride reppe af ny Annexes A43 4 Basin processing e Close the MainView1 window Select the ProjView document and open ProjView named ProJdhk 4 1 Revise sub basin delineation A Subdivide a basin e Add the hydrological station location theme hydro_gage shp to the ProJhk window e Make the hydro_gage shp theme active in the ProJhk window e Zoom in on the Upper Andheri Khola gauge location a e Select the basin subdivide tooll AEI click on the cell where the Upper Andheri Khola gauge station is located e Rename the point as Gage 8 e Click OK e Verify the result and click Yes fe ois AL A A PPP oie EF a pA ey a Ao ies eee ee esp et i ee Gage 8 Cancel Mame the point A el im re el g LHN EF paip h ee E H Er A44 Resource Manual on Flash Flood Risk Management Module 2 e Zoom in on the Kukhuri gauge location station id 7 subdivide the basin at this location as mentioned above point name Gauge 7 The result of basin subdivision is shown below B Obtain the river profile and subdivide from the grade break e Activate the River shp theme e Select the stream segment shown in the figure below with the Select tool e Select Basin preprocessing River Profile e Select the point by Delineate tool 2h e Click on the profile approximately where the grade breaks as shown in th
31. ability Map In this exercise you will look at the input data for a vulnerability analysis The final aim of the exercises at the national scale is to make a qualitative risk map displaying the areas where there is a high probability of a disaster occurring For this we also need to know the vulnerability the degree of loss to a given set of elements at risk resulting from the occurrence of the phenomenon Elements at risk are the population properties economic activities etc at risk within a given area A vulnerability classification can be carried out in the same way as the method used in the creation of the hazard map by assigning weights to each of the factors and summing the weights The following maps are used for this Infraseg Major infrastructure Industry Main industrial centres Concentr Concentration of economic activities Popdens Population density The last map Popdens does not exist yet You will first have to create it This will be done in the first step of the analysis A8 Resource Manual on Flash Flood Risk Management Module 2 Creating a population density map For this calculation you will need the following input data e The map Colombia from which you can calculate the area of each department e A table with the number of inhabitants per department Table below The map is created using the following steps e First you will calculate the histogram of the map Colombia and find out the area in square metres
32. agement Module 2 e You will see the following global summary table on the screen X l a p L gt ii T J SLT a ee Fee To fe rip Propet duu Seder Mun Queene Sete Bun 2d De Ersin Pda Praf End oF Bac ad 9 Gh ke e Med Bebe n Dkt Copie fire UA 1674808 Genra ema dures PRI koksa lint MM 100d Mo B Element graph e In Watershed Explorer select the Components tab to open the basin model ie fae Wee Ceepsere Ppi Corps Bor fedi rin ee ee oe M ae pte de yp Te ees Cre a cored Comes Bendi ytd tamer Heater ee Phe Deny heer ore prar dt Gere BT ard Call Pe p aac Fe iy miga Me Erna erg u ire ower Harre 7 The current simulation run is shown in brackets in the basin map title bar e Select one or more elements e g sub basin R440W440 in the basin map by clicking with the arrow tool e Select Results Element Graph e The result will be shown in the Desktop area Annexes A87 2 Deeg ea a ae ee fier bes i d aii t i pE Heberg y aa ee PI uo a EE 1 5 w L200 Ba i 1 Con ic ee ee Mee ee Legend Ma CURRENT Ferme SHAA Arnd bees al Pees ed siam Fa CURR Ferree BARA Firn Perri ations Lari a faun CLIFRIFRT Ferra Bikri Firad ict ed Mom o Fh Cerei Fief PHRAS Eoria Sha Mean B CURRENT Bertai BHSMAHAE Fiind kaiii e You can display the element time series table and element summary in the same way by selecting Results E
33. ake type is either V trough valley lake C cirque lake M end moraine dammed lake L lateral moraine dammed lake or B blocking lake e Open attribute table Rol_gl e Type the following formula on the command line Pot_danger iff class V or class C or class M or class L or class B and area_km gt 0 5 and Area gt 100000 and dist_gr lt 500 1 0 4d e If there are more criteria to define lake as potentially dangerous you should try to find those and write the appropriate syntax A112 Resource Manual on Flash Flood Risk Management Module 2 References ICIMOD 2007 Inventory of Glaciers Glacial Lakes and Identification of Potential Glacial Lake Outburst Flood GLOFs Affected by Global Warming in the Mountains of Himalayan Region Kathmandu International Centre for Integrated Mountain Development ICIMOD DVD ROM LIGG WECS NEA 1988 Report on First Expedition to Glaciers and Glacial Lakes in the Pumqu Arun and Poiqu Bhote Sun Kosi River Basins Xizang Tibet China Sino Nepalese Investigation of Glacier Lake Outburst Floods in the Himalaya Beijing Science Press Mool P K Bajracharya S R Joshi S P 2001a Inventory of Glaciers Glacial Lakes and Glacial Lake Outburst Floods Monitoring and Early Warning System in the Hindu Kush Himalayan Region Kathmandu International Centre of Integrated Mountain Development and United Nations Environment Program ICIMOD UNEP Mool P K Wang
34. all hydrological elements in the basin model Unselect all selected hydrological elements in the basin model Open the select special dialogue Open the maximum extents editor Open the map layer selector editor Zoom in by a factor of 25 Zoom out by a factor of 50 Zoom to the current element selection Zoom out to the maximum extents Toggle Element Icons Toggle Element Names Toggle flow direction arrows on reach elements Toggle showing gridlines in basin map Clear all messages from the message window A6O Resource Manual on Flash Flood Risk Management Module 2 Components Menu Open the basin model manager Open the meteorological model manager Open the control specifications manager Open the time series data manager Open the paired data manager Open the grid data manager Open a summary table containing all hydrological elements in the basin model Open a graph of results for the current selection Open a summary table for the current selection Open a time series table for the current selection Tools Menu Generate reports of basin model or simulation run results using a custom template Select default methods for the current project Change properties for the program Open wizard to create a simulation run Select a simulation run from list of available runs Open the simulation run manager Open wizard to create an optimisation trial Select an optimisation trial from list of available trials Open the optimisat
35. applied to the basin model if you wish You may instead apply a ratio to the outflow computed by the sub basin and source elements in the basin model before routing the outflow downstream through the element network You must choose between applying no ratio a precipitation ratio or a flow ratio The same ratio is applied to all elements In this case we apply no ratio C Checking parameters e Select Compute Check Parameters e You will see a message showing whether there is any error or warning Revit doe Pee qe gee ei are on ieee OS pe 2 eee ee ee de eee ee eee ee bate hc 2 PESTE pms p gee J eee Area ae ee ra ee ey oe PST 1c no Se jiri me h See eer Det Cee el Cee OY el a E PESTE fae i eee eed ee ee eee ee ee F eee P ee bA Bb ee Reid eee Pee en eee eee pa om bose rreestiod Weed he ae pe el eee ee ee eel eee eerie a ja pr j u Messages issued under parameter checking are classified as notes warnings or errors Notes are used to communicate general information to the user They may also be used to indicate actions taken where the result was within established guidelines Warnings are used when the program must take action in order to continue the simulation and the actions taken may conflict with the intentions of the user Action messages should be checked to make sure the program made appropriate assumptions Error messages are used to indicate problems that stop the simulation from proceeding These messages can be
36. arithmetic mean value of the highest glacier elevation and the lowest glacier elevation and lowest elevation elevation at toe of the glacier Morphological classification The study uses the morphological matrix type classification and description proposed by Muller et al 1977 for the TTS to the WGI Each glacier is coded as a six digit number the six digits being the vertical columns of Table 3 The individual numbers for each digit horizontal row numbers must be read on the left hand side This scheme is a simple key for classifying all types of glaciers throughout the world A100 Resource Manual on Flash Flood Risk Management Module 2 Table 3 Classification and description of glaciers Form Frontal Longitudinal Major source of Activity of characteristic profile nourishment tongue Primary classification Uncertain or miscellaneous Uncertain or Normal or Uncertain or Uncertain or Uncertain miscellaneous miscellaneous miscellaneous miscellaneous Compound Piedmont Even regular Snow and or Marked retreat basins drift snow Compound Expanded foot Hanging Avalanche and Slight retreat basin or snow Simple basin Superimposed Stationary ice Cirque Ice fall Slight advance Niche Confluent Interrupted Marked advance Continental ice sheet Ice field ce cap Outlet glacier Valley glacier 7 g a e Mountain glacier Grater TS Possible surge eam te T snow field elese lep C oo e Rock gla
37. atershed Explorer expand the project name and select the junction elements e g Outlet_A e Inthe component editor select the Options tab e Select Outlet under Observed Flow and Observed Stage from the respective dropdown menus e Enter the reference flow and reference label under Ref Flow M3 S and Ref Label if available e Define the observed stage and observed flow values for other junction elements in the same way Annexes A81 _ Metron cha Meds D a des Ih Dai Ct angoa Caalinrn Basin Kener Profi Element Harme Dulk A Diaan Pa Oui Dhaira ja iat Dar DHhE at Foes H Ha Ll C Reach Ts Although conceptually a reach element represents a segment of a stream or river the actual calculations are performed by a routing method contained within the reach Six different routing methods are provided see Table 10 Each uses a hydrological routing methodology rather than a hydraulic approach which implements the full unsteady flow equations Each method included in the program provides a different level of detail not all methods are equally good at representing a particular stream H B E H S In Watershed Explorer expand the element name e g R450 and select the reach element In the component editor select None under Routing Method and Loss Gain Method You can choose any routing method if the data required for reach methods are accessed or available Table 9 Ei RAO
38. azclas asthe Primary domain and Vulclas as the Secondary domain Press the Create button next to the Domain list box The Create Domain dialogue box is opened Create a class domain Risk with three classes Low risk Moderate risk and High risk Close the domain editor and click OK in the Create 2 Dimensional Table dialogue box The two dimensional table is opened It will contain undefined values for all combinations Below we have already filled in some of them for example e When the hazard is very low it doesn t matter whether the vulnerability is low or high the risk will be low in all cases e When the vulnerability is very low meaning that the area doesn t contain any important elements at risk the risk is always low Annexes A11 a a T A Verytow Low Modere High voyew tow iow tow low Low Low Haza oae kee anm fF iw o oe o Veyron low Fill in the missing classes in the two dimensional table above Give the reason for assigning the risk classes high medium or low risk Click the upper left field in the two dimensional table Edit the fields using the left arrow lt Press the down arrow J to go to the next field Fill in the entire table It is faster to work with the arrow key than to click each field select the right name from the list box and click another field You only have to click the upper field of the next column when you are finished with the last field of the previous column
39. b e Select the control specification June 1999 in Watershed Explorer e Enter the Start Date End Date Start Time End Time and the Time Interval from the dropdown menu to set the control specifications Annexes A67 Control Specifications Components Mame June 1999 Description 26 June 29 June during the i E Start Date gddMMMYY YY 26Jun1 999 Start Time HH mm 06 30 End Date ddMMMY YYY 29Juni 999 End Time HH mm 06 30 Time Interval 30 Minutes Note The format for specifying a date is two digits for the day followed by the three letter month abbreviation and the four digit year The time should be specified by a two digit hour followed by a colon and two digit minutes The program uses a 24 hour clock notation Time windows can only be entered with minute resolution e You can copy delete or rename the control specifications by selecting in Watershed Explorer and right clicking the mouse button on control specifications Similarly you can create many control specifications from the component menu as outlined above 3 Entering shared component data HEC HMS simulation requires time series precipitation data in order to estimate average rainfall for the basin A time series of discharge and water level often called stage data is helpful for calibrating a model and is required for optimisation Other kinds of time series data are also used Time series data is stored in a project as a gauge Som
40. centroid river length and river slope With the input from HEC GeoHMS HEC HMS can be used to select a hydrological model select basin characteristics input meteorological data create control specifications run simulations and calibrate and validate the model Sample data are included for use in the practical training exercise The data files include DEM dem_ jhik hydrological gauge location hydro_gage shp rainfall gauge station location rain_gage shp curve number grid cn_grid 2 year 24 hour rainfall intensity grid rinten_inch Manning s roughness coefficient grid manning_n discharge watershed and precipitation data The sample data are stored under Jhikhu data The sample HEC GeoHMS project and HEC HMS model are stored under Jhikhu sample Software Requirements Arc View 3 2 or later with Spatial Analyst 1 1 extension or later HEC Geo HMS 1 1 HEC HMS 3 1 0 Note The spelling used for the text is UK English but technical terms are in US English as the program itself is in this form A26 Resource Manual on Flash Flood Risk Management Module 2 Contents Preface Overview Pal l Working with HEC GeoHMS Open Arc View and load HEC GeoHMS 2 Graphics user interface with HEC GeoHMS extensions 3 Preprocess the terrain model 3 1 Setup the working directory with terrain and stream flow gauge data 3 2 Terrain preprocessing 3 3 Hydrological model setup 4
41. cier Remnant O S S Each glacier can be represented as a six digit number following Table 3 For example 520110 represents 5 for a valley glacier in the primary classification 2 for compound basin in Digit 2 O for normal or miscellaneous in frontal characteristics in Digit 3 1 for even or regular in longitudinal profile in Digit 4 1 for snow and or drift snow as the major source of nourishment in Digit 5 and O for uncertain tongue activity in Digit 6 Known surge The details for the glacier morphological code values according to TTS are explained below Digit 1 Primary classification 0 Miscellaneous Any not listed 1 Continental ice sheet Inundates areas of continental size 2 Ice field More or less horizontal ice mass of sheet or blanket type of a thickness insufficient to obscure the sub surface topography It varies in size from features just larger than glacierets to those of continental size 3 Ice cap Dome shaped ice mass with radial flow 4 Outlet glacier Drains an ice field or icecap usually of valley glacier form the catchment area may not be clearly delineated Figure 1 1a 5 Valley glacier Flows down a valley the catchments area is in most cases well defined 6 Mountain glacier Any shape sometimes similar to a valley glacier but much smaller frequently located in a cirque or niche 7 Glacieret and snowfield A glacieret is a small ice mass of indefinite shape in ho
42. da D Bajracharya S R Kunzang K Gurung D R Joshi S P 2001b Inventory of Glaciers Glacial Lakes and Glacial lake Outburst Floods Monitoring and Early Warning Systems in the Hindu Kush Himalayan Region Kathmandu International Centre of Integrated Mountain Development and United Nations Environment Program ICIMOD UNEP Muller F Caflish T Muller G 1977 Instruction for Compilation and Assemblage of Data for a World Glacier Inventory Zurich Temporary Technical Secretariat for World Glacier Inventory Swiss Federal Institute of Technology Zurich Annexes A113
43. e 2 Table 1 Accuracy rating adopted from Muller et al 1977 Index s _ sArea length Altitude m Depth Mean glacier thickness and ice reserves There are no measurements of glacial ice thickness in most parts of the Hindu Kush Himalayan region Measurements of glacial ice thickness in the Tian Shan Mountains China show that glacial thickness increases with the increase in area LIGG WECS NEA 1988 The relationship between ice thickness H and glacial area F was obtained as H 11 32 53 21 F As there are no other measurements of ice thickness this formula has been used to estimate the mean ice thickness in the glacier inventory The ice reserves are estimated by mean ice thickness multiplied by the glacier area Muller et al 1977 roughly estimated the ice thickness values for Khumbu Valley using the relationship between glacier type form and area see Table 2 The same method was used by WECS to calculate the thickness values for Rolwaling Valley in Nepal According to Muller et al 1977 the mean depth can be estimated with the appropriate model developed for each area by local investigators For example the following model was used for the Swiss Alps haan A Where his the mean depth Fis the total surface area and a and bare arbitrary parameters that are empirically determined The measured depth is shown on the data sheet only if the depths of large parts of the glacier bed are known from literat
44. e 2 e Select the Objective Function under Trial 1 as follows E4 Jhiku_runoff Sy Simulation Runs AA currenti 5 Optimization Trials S a Trial 1 fon Objective Function e Select the desired method for objective function measures under Method e Select the amount of missing flow data that will be accepted under Missing Flow In general the observed flow record at the selected element location should not contain any missing data The default value is 0 0 percent Compute its Optimization Trial Objective Function Name Trial 1 Method Peak Weighted RMS Error Location Outlet _A Missing Flow 0 0 Start Date ddMMMy yyy 26Jun1999 Start Time HH mim 06 30 End Date ddMMMy yy 29Jun1999 End Time HH mm 06 30 Add a parameter e Right click the mouse button on Optimization Trial e Click Add Parameter in the context menu Parameter 1 will be added in the Watershed Explorer window C Jhiku_runoff 5 y Simulation Runs Be Current 2 54 Optimization Trials Ay Trial 1 ce Objective Function Se Parameter 1 e You can add delete by right clicking the mouse button over the parameter e g Parameter 1 and selecting Add Parameter or Delete Parameter Annexes A91 Specifying parameter information e Select the parameter in which you want to specify the information here Parameter 1 e Select the desired element under Element and the desired parame
45. e Function The table will open B Optimised parameters table e Select Results in Watershed Explorer e Select Optimization Trials Trial 1 Optimized Parameters The table will open Poet ee ure a rageres Tri Trem er eel Trimi ote Ee Ce HE Pua Pe oe Pr F fired of Trim ha bee oe eh Pisi et cake Pk eel Waay bre Come Le Pe ee Pree Cae ioe ee ee Dar a Boe rca os ioe Ti ar Cee a Faran i aE a oe Cael Fn iy ZETTEL E neme Fiore Fj TE i BSP T Enim reir oe aa wih F 4 0 mh 0 Bo ee E eS Th IL oy at Soe LE ae TET T 00 C Hydrograph comparison graph The hydrograph comparison graph shows the computed outflow and observed streamflow at the objective function evaluation location e Proceed as above but select Hydrograph Comparison You will see the hydrograph comparison graph Annexes A93 Hyrograpn Comparison Fiye PA La uno Lii OTLET S TTEA Pe D Flow comparison graph Lah mirlar O00 Sadun1 goo OLTL OT A OPT TA LOO eo The flow comparison graph shows the computed flow plotted against the observed flow If the computed flow is exactly equal to the observed flow then the data will plot exactly on a 45 degree line However in almost all cases the match is not exact and there will be scatter in the data around the 45 degree line Data points before the time of peak flow are shown with red circles and points after the time of peak flow are shown with b
46. e Table and select the table Seismic Press OK Now the table Seismic is linked to the map seismic Follow the same procedure for the other maps Landslid Volcanic Tsunami and Beach The creation of weights for the other three maps Inundat River and Topograp will be done differently As practically all units will receive the same weight it is better to use another method of reclassification a map calculation formula Annexes Ad Step 2 Renumbering the parameter maps to weight maps Now that you have made a table with weight values for the parameter maps we can renumber the maps to weight maps For this we will use the operation Attribras From the menu of the Main window select the menu items Operations Raster Operations Attribute Map Select Seismic as the raster map select Seismic asthe table and Weight asthe attribute Type Wseismic as the output map Type Renumbered map Seismic with weights as Description Click Show and OK In the Display Options dialogue box select the representation Pseudo Click OK The weight map is displayed If you click on a unit in the map you will no longer see a description but a number which is the weight assigned earlier To check this with the original map Seismic use the Pixellnfo You can do this by selecting File Open Pixel Information In the Pixel Information window select File Add Map and select the map Seismic When you move the mouse over the map you will see the na
47. e component methods require paired and some grid data sets In this example we will only use time series precipitation water level and discharge data 3 1 Creating and entering time series data A Precipitation data e Select Components Time Series Data Manager e Select Precipitation Gages from Data Type dropdown menu e Click New irete Serves Date MIE Daia Ta Moti La Dimi p clita A68 Resource Manual on Flash Flood Risk Management Module 2 e Enter the name of the precipitation gauge and description e Click Create e You can create as many gauges as available in the study area site e Close the time series data manager window Create A New Precipitation Gage E Name i Gage 04 Description Baghkhor fe A new time series data component will be added in Watershed Explorer as shown below _4 eu prot p Pret Control SpecPicstions fy ue 1 C Tire Sores Dake ih Tre Series Gage Che rege ee Pusat hace Dali Gertie Marnie Eriry Line bare Abeer fire jiii 15 Maden Latibuices Degg Litibaj Mit Lahu Saah Longbude Dayenr Liepa Hii Longhuse Seoni RIRE e Expand the gauge in Windows Explorer as shown below Annexes A69 Jhiku_runoff B 24 Basin Models i g FroJhk 24 Control Specifications ED June 1999 Time Series Data Precipitation Gages ES Gage O4 bBo O1Jan2000 00 00 O2Jan2000 00 00 FS Gage 06 e
48. e figure below Annexes A45 S Ele Cht For ProJhk arid values along the selected line River shp on fillgrid e Click Yes amp Split the Basin and River xi Grade break Subdivide basin and river at the selected point no remove point graphics cancel leave point graphics Cancel e Name the point break1 Su bdivide Basin and River x Name the point bea n Cancel Gh order he tabedveied bau aral reer as ad e Review the result and click Yes A46 Resource Manual on Flash Flood Risk Management Module 2 The result of the basin subdivision is shown below Note The basin merge menu merges sub basins that share a common confluence or are adjacent in an upstream and downstream manner For this select two adjoining sub basins and select basin merge in the basin processing menu However in this case it is not applicable 4 2 Basin characteristics Note that outputs of basin characteristics are saved in attribute tables of the respective theme A River length e Select Basin Characteristics River Length e Click OK B River slope e Select the Basin Characteristics River Slope e Select the DEM s Vertical Units as Meters because the terrain data has vertical units in metres e Click OK e Click OK again Geko DH s arta iar Annexes A47 The derived river length and slope calculations are added to the River shp attributes table ae item of thd Shp
49. ect the basin model projhk basin Basin will be imported in the project Annexes A63 Select C jh PEMPE places _ Fies of type HEC HMS Basin Files basin B Add background map Select View Background Maps Basin model created with HEC GeoHNsS vi i Beta im Retard Aap come om coe Click Add Select the background map Click Select A64 wens onm f Paama Pim a reo HEH Ma ik Pami ie Browse the location where the background map exported from HEC GeoHMS is located Resource Manual on Flash Flood Risk Management Module 2 The imported basin model and background map are shown below oe peer Bloat Pre a gii F ma p i C Description of the hydrological elements of the basin model Different kinds of hydrological elements are used in the basin model The description of each element is given below Table 7 Different kinds of hydrological elements that can be used in the basin model Hydrological o Subbasin The sub basin is used to represent the physical watershed With a given precipitation M outflow from the sub basin element is calculated by subtracting precipitation losses calculating surface runoff and adding baseflow Len The reach is used to convey streamflow Inflow to the reach can come from one or many Reach upstream elements Outflow from the reach is calculated by accounting for translation and atte
50. en created in cyhikhusampleProthk A56 Resource Manual on Flash Flood Risk Management Module 2 I Export lumped basin model to HEC HMS This model is the input for HEC HMS It should be used for a hydrological model with lumped basin parameters e Select HMS Lumped Basin Model e Make anote of the file name and location and click OK S HMS Basin file creation X The Basin file FProlhk basin has been created in co hikhussamplesprojhk Annexes A57 Working with HEC HMS A58 Resource Manual on Flash Flood Risk Management Module 2 1 Getting started with HEC HMS 1 1 HEC HMS overview Open the HEC HMS program You will see the following program screen rs cat a A Wenu bar s s e S Toolbar Window Explorer bee Bob po Piek oe ne Desktop i Component ii Editar iF L z P i pa mam Er a Annexes A59 A Menu bar The following commands are available under the different menu items comma a a File Menu Create a new project Open a project Import HEC 1 files basin or meteorological models Save the current project Make a copy of the current project Delete the current project Rename the current project Print the currently selected item Exit the program Cut or delete the selected hydrological element s Make a copy of the selected hydrological element s Paste the copied hydrological element s Select
51. epth method type type 1 type 1A type 2 type 3 The inverse distance method was originally designed for application in real time forecasting systems It can use recording gauges that report at regular intervals e g 15 minutes or 1 hour It can also use gauges that only report daily precipitation totals Because it was designed for real time forecasting it has the ability to automatically switch from using close gauges to using more distant gauges when the closer gauges stop reporting data The latitude and longitude of the gauges is used to determine closeness to one or more nodes specified in each sub basin Optionally an index depth can be assigned to each gauge The index is used to adjust for regional bias in annual or monthly precipitation This method uses separate parameter data for each gauge used to compute precipitation and also uses separate parameter data for each sub basin in the meteorological model e Select Components Meteorological Model Manager e Click New e Click Create Create A Mire bubeterserskeasi helide amar il eas aera Cee bed Pee gee eee E fee Cama Annexes A73 e Close the Meteorological Model Manager window A Meteorological Models component will be created in the Watershed Explorer window as shown below e Select Jhikhu In Dist under Meteorological Models e Inthe Meteorology Model tab in component editor select the Precipitation method as Inverse Distance from the dropdown men
52. er map as Dem Type 1_year as Output Raster Map Select 1 Year Flood as domain Click Show to generate the map Double click the raster map 1_ year from the catalogue to open Add Wards polygon map with the boundaries only option as a layer Check the wards affected by 1 year floods in the Rathnapura Municipal Council Area A16 Resource Manual on Flash Flood Risk Management Module 2 Ward wise inundation area estimation To find the ward wise inundation area in Rathnapura town use the Cross Operation in ILWIS By crossing Wards and 1_ year raster maps the area belonging to each ward in Rathnapura MC can be determined 4 From the Operations menu select Raster Operations and click Cross The Cross Dialogue box opens Select 1_year as the 7 Map Select Wards as the 2 Map Type 1_year_ww for the Output Table name Type 1 year ward wise flood map as the description Click the Output Map check box to select and type 1_ year_ww as the output map name Click Show to generate the map Area calculations You can use the histogram for area calculations in raster maps Right click the raster map 1_year_ww From the Context Sensitive menu select Statistics and click Histogram to create the histogram for the raster map 1_year_ww Apply the same procedure to create flood scenarios for 2 5 10 20 30 50 100 and 200 year return periods Creating flood zonation maps In this exercise the Dem raster ma
53. essage box Teme bend e J eme Annexes A35 The previous screen does not appear to be 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 D Stream definition This 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 e Click on View Properties This opens the properties dialogue box e The map units are the data units In this case the DEM data units are measured in metres e Specify the Map Units as metres e The distance units are the reporting units in Arc View Specify the Distance Units as kilometres e Click OK e Save the project es a he Caor late Mereni dure i Sle 12st aE Canara Co Map Unir eee I I N E l Fumi Barei Ji bedeeet Paipa Coden D Te i Sect oe Cereri A36 Resource Manual on Flash Flood Risk Management Module 2 e Select Terrain preprocessing Stream Definition e Confirm that the input of the FlowAccGrid is FaccGrid The output of the StreamGrid is StrGrid StrGrid is a default name that can be renamed by the user e Click OK ep ee Aa ala x Fires Teed Faena Shear ad ata e r m e Select the thresh
54. fdirgrid and of LinkGrid is strinkgrid The output of the WaterGrid is WshedGrid WshedGrid is a default name that can be renamed by the user e Click OK e Click OK again A38 Resource Manual on Flash Flood Risk Management Module 2 Tragic ipu Fecces a ages _ rua Seep G Watershed polygon processing This step converts the grid file of watershed delineation to vector representation e Select Terrain preprocessing Watershed Polygon Processing e Confirm that the input of WaterGrid is wshedgrid The output of the Watershed is Wshedshp shp Wshedshp shp is a default name that can be renamed by user ad JE 7 o a a melee _ amp amp a tered amp amp Ee e Click OK e Click OK again yi Werechy Srg Bibi rig Hg FE rps ijai Sen pe Annexes A39 H Stream segment processing This step converts the grid file of the stream derived above to vector representation i e into a shape file e Select Terrain preprocessing Stream Segment Processing e Confirm that the input of the LinkGrid is strinkgrid and of FlowDirGrid is fdirgrid The output of River is River River is a default name that can be renamed by the user e Click OK e Click OK again Uriin trii grl ka EDn Fem iw I Watershed aggregation This step aggregates the upstream sub basins at every st
55. for each department e Second you will make a table Colombia and join it to the histogram table to obtain the area of each department e Third you create a new column Population in the table Colombia in which you enter the population numbers per department e Fourth you divide the column Population by the column Area to find out the population density e Finally you reclassify the map Colombia with the column Popdens and create the population density map In the Main window select the following menu items Operations Statistics Histogram Calculate the histogram for the raster map Colombia Create a new table Colombia with the domain Colombia In the table window read in the areas of the department by executing the following formula Area Colombia his Aread Accept the default values Create a column Population type Value with a range 0 to 6000000 and precision 1 Fill in the values from the table below Number of inhabitants per department Surrounding countries Surrounding countries ees s nian Amazonas sid P3020 Haila 647756 aw O o e S Annexes A9 er e After entering the values calculate a column Popdens population density number of persons per km Note that the values in the column Area are inm e Close the table window Creating the vulnerability map In the same way as the preparation of the weight maps used for the hazard map a series of weight maps should be created to p
56. for precipitation 1 Outlet is Station 2 Annexes A71 Miho dope Hei Ea ri y ii Dae 23 Bnin Model Chutiee hina he Caan july Tire Series Gage Time Wandea Table Graph fire IM Heim Diha deta Eim TEE oa F h Es i Lovo Gidi L200 Cun S0000 nadim e i ag ee Wea a HAHA 1330 CL OGG0000 ETATE i k 001999 14 20 a 7 a1 200 0 CA O1Nu 59 26 00 O 1720000 B ei 600 a wg ey bh ie tial CA0 F700 nano Od kde bn ion i 0131959 16 00 01700000 oq Adare baa Otho Giada todi EE aderat da Padian MNOOO OTE 10170 Opened basin model Proti at time O8duncOO 15 04 11 GIFS a0 CLOMnond mas 2030 Taig on Loon CLII 2130 0 0830000 SETIN 7a pini 0021999 22 30 1 060000 OUND 7 00 LO C Water stage data e Create the gauges Gage 07 Gage 08 and Outlet for water stage data in the same way as for precipitation and water discharge e Input the time series gauge information define the time window and input the table data as described above for precipitation and water discharge A72 Resource Manual on Flash Flood Risk Management Module 2 4 Creating a meteorological model Different methods are used to describe precipitation evapotranspiration and snowmelt to make a meteorological model Only some basin models need the evapotranspiration method and snow melt is not applicable in our case Thus only precipitation is used to develop the model
57. g orientation of ablation area towards S SE SW Retreat _condition iff orien_abl S or orien_abl SEK or orien_abl SW fast retreating not fast retreating d 10 This syntax is used to classify glaciers based on area based class domain area_cl Area_cl clfy area_km area_cl 4 Annexes A111 Syntaxes related to handling glacial lakes attribute data This syntax is used to find the area of glaciers associated with the lakes e Open attribute table Rol_ gl e Type the following formula on the command line Join table rol_gr tbt Area_km Associated_gr 4 Associated_gr must have the same domain of the table rol_gr This calculation derives the area of lakes within proximity to glaciers of more than 50 to less than 500 metres e Type the following formula on the command line Dist 500 Afi dist _or gt 50 and dist 7 lt 500 1 0 a This calculation derives the area of lakes within proximity to glaciers of more than 500 to less than 2000 metres e Type the following formula on the command line Dist 2000 aff4 aist_or gt 500 and dist_or lt 2000 1 0 identification of potentially dangerous glacial lakes This is an example of an ILWIS syntax to calculate which lakes might be considered potentially dangerous e The criteria used here are mother glaciers associated in contact with the lake should have an area exceeding 0 5 km the lake should be bigger than 100 000 m the l
58. gation to encourage and support improved early warning practices in developing countries small island developing states economies in transition and other disaster prone countries with special circumstances Primarily affected countries equally have a primary responsibility to conduct a rigorous audit of the effectiveness or consequential identification of needs of their early warning capabilities The conduct of post mortem assessments of regional and national warning system capabilities are particularly relevant following any disaster event Specialized regional and global centres involved in the preparation and dissemination of warnings such as the WMO Regional Specialized Meteorological Centres provide important links to national early warning systems The application of their technical capabilities and the utility of their products should be carefully integrated with the needs of the countries being served including any necessary clarification about the warning responsibilities between these centres and national agencies in the same region A21 A22 In the interest of protecting people from the risk of natural hazards it is essential that the formulation and presentation of warnings be based on the best available technical and scientific knowledge and free of political distortion or manipulation International bodies and regional organisations must work to maintain the vital importance of timely exchange of and unrestricted access t
59. gerous lakes The last part of the Annex includes some ILWIS software syntaxes for handling data regarding glaciers and glacial lakes The syntaxes are of two types 1 to make some basic calculations about glaciers and glacial lake attribute data and 2 to identify potentially dangerous glacial lakes based on a set of criteria Inventory of Glaciers and Glacial Lakes and Tdentitication of Potential Glacial Lake Qutbwret Foods Spatial Data Input Attribute Data Handling and Image Processing of Rolwaling Valley Nepal mba ee j a o HA pia lp ea laan r ja a a t An open source version ILWIS 3 4 Open can also be used which is freely downloadable from lt http 52north org index php option com_ projects amp task showProject amp id 30 amp ltemid 127 gt Annexes A97 Part 1 Methodology for Inventory of Glaciers and Glacial Lakes The methodology used for mapping and inventorying glaciers is based on the instructions for compiling and assembling data for the World Glacier Inventory WGI developed by the Temporary Technical Secretary TTS at the Swiss Federal Institute of Technology Zurich The methodology for the inventory of glacial lakes is based on that developed by the Lanzhou Institute of Glaciology and Geocryology present name Cold and Arid Region Environmental and Engineering Research Institute CAREERI the Water and Energy Commission Secretariat and the Nepal Electricity Authority LIGG WECS NEA 1988 The inventory of
60. h Flood Risk Management Module 2 Annexes No Department Percentage high risk A13 Application of GIS to Flood Hazard Mapping This exercise and accompanying data were made available by M B Usamah Asian Disaster Preparedness Center Thailand Summary This exercise was developed by the Asian Disaster Preparedness Center and University of Rahuna and is based on a case study on Rathnapura Municipal Council Sri Lanka This Annex provides a general idea of how to prepare a flood hazard map using GIS and therefore is presented in a simplified way The exercise is based on GIS software ILWIS 1 Data Evaluation The base data set consists of a series of segment and point maps Name Format Description S Open ILWIS program and set your working directory to where data are stored Display MC_boundary Wards Stream and Ra_city maps and check the information for Rathnapura Municipal area city centre and about the wards within the municipal area the stream and the Rathnapura city location Display Contour map and check the elevation ranges within the Rathnapura municipal area 2 DEM Creation The main objectives of this exercise are e To create the DEM using contour data e To create different flood scenario maps for Rathnapura town e To estimate the flood inundation areas of Rathnapura town 1 An open source version ILWIS 3 4 Open can be used which is freely downloadable from lt http 52nort
61. h org index php option com_projects amp task showProject amp id 30 amp ltemid 1 27 gt A14 Resource Manual on Flash Flood Risk Management Module 2 To generate the DEM segment map Contour Is used in this exercise Open by double clicking Contour map Double click map properties Select coordinate system Rath from the drop down menu From the Operations menu select Interpolation and then the Contour Interpolation option The Interpolate Contour Map dialogue box is opened Select Segment map Contour Type Dem as Output Raster Map and select GeoReference as Rath For the Description type DEM created from the segment map Contour Accept all other defaults and click Show Click OK in the Display Options Raster Map dialogue box The map is displayed Now the DEM is generated You can check the details of the DEM using various tools and by overlaying other maps on the DEM Click on several places on the map and read the altitude values Use the Zoom tool to zoom to an area on the map and check the value of a pixel by moving the mouse pointer within a pixel Add MC_boundary map as a layer using the Add layer tool From the Display Options Polygon Map dialogue box select Boundaries Only Set the Boundary Color as Brown and Boundary Width to 2 Click OK to display the map You can change the default Representation using the Display Options Raster Map dialogue box Double click the map Dem in the Layer Manageme
62. he default method is the univariate gradient method This method is always used if only one parameter is selected e Accept the default tolerance and maximum number of iterations or define the value under Tolerence and Max Iterations Components Compie Results Np Cptirigahor Trig Sane Trial Liars Birce Curetl las Eat Petit Lirie Oe ache Torre OCT Max terete D C Objective function The objective function measures the goodness of fit between the computed outflow and observed streamflow at the selected element Six different functions are provided that measure the goodness of fit in different ways see Table 11 Table 11 Objective function methods Peak weighted RMS error Modification of the standard root mean square error that gives greatly increased weight to flows above average and less weight to flows below average Sum of squared residuals function Gives increased weight to large errors and less weight to small errors Sum of absolute residuals function Gives equal weight to large and small errors Percent error in peak flow function Ignores the entire hydrograph except for the single peak flow value The percent error in volume function Ignores peak flow or timing considerations in favour of the volume Time weighted function Gives greater weight to errors near the end of the optimisation time window and less weight to errors early in the window A90 Resource Manual on Flash Flood Risk Management Modul
63. ied point use to delineate basin at batch points Interactive flow path Specify a different longest flow path by clicking on a different most remote point in the sub basin Define TR55 points Move the program generated points AA the break between sheet flow and shallow concentration flow and BB the break between shallow concentration flow and the channel flow to a user specified location 3 Preprocess the terrain model 3 1 Setup the working directory with terrain and stream flow gauge data e Save the project as JhikhuSample apr or any name in the working directory C training The location of the project is important because subsequently derived data sets are stored relative to the project location e Open a New Main View e Add the dem_jhik as a grid theme in the Main View using the Add Theme button Sel e Turn on the dem_jhik theme Change no colour symbol to no data from the legend editor Annexes A33 3 2 Terrain preprocessing A Fill Sinks e Select Terrain preprocessing Fill Sinks e Confirm that the inout of RawDEM also referred to as the unfilled DEM is dem_jhik The output of the HydroDEM is FillGrid FillGrid is a default name that can be renamed by the user Remember the name of HydroDEM if you change the default name e Click OK This step takes some minutes The output data will be saved in the subfolder BaseData within the folder where
64. ing in close proximity and too small to be assessed individually 9 Remnant An inactive usually small ice mass left by a receding glacier Figure 1 2a Compound basins Figure 1 2b Compound basin Figure 1 2c Simple basin Figure 1 2d Cirque Figure 1 2e Niche A102 Resource Manual on Flash Flood Risk Management Module 2 Digit 3 Frontal characteristics 1 2 Piedmont ice field formed on low land with the lateral expansion of one or the coalescence of several glaciers Figures 1 3a and b Expanded foot Lobe or fan of ice formed where the lower portion of the glacier leaves the confining wall of a valley and extends to a less restricted and more level surface lateral expansion markedly less than for piedmont Figure 1 30 Lobed Tongue like form of an ice field or ice cap see Figure 1 3d Calving Terminus of glacier sufficiently extending into sea or occasionally lake water to produce icebergs Confluent Glaciers the tongues of which come together and flow in parallel without coalescing Figure 1 3e Figure 1 3a Piedmont Figure 1 3b Piedmont Figure 1 3c Expanded Figure 1 3d Lobed Figure 1 3e Confluent Annexes A103 Digit 4 Longitudinal profile 1 2 3 4 5 Even regular Includes the regular or slightly irregular and stepped longitudinal profiles Hanging Perched on a steep mountain slope or in some cases issuing from a steep hanging valley Cascading Descending i
65. ins miscellaneous tools dealing with assigning Discdas Theme T roles for data sets and developing graphical output This menu will Eae not be used in the present exercise Set Theme Tag Value Remove a Theme Tag Key Wier bo maga Shaded DEM to Image A30 Resource Manual on Flash Flood Risk Management Module 2 Table 2 MainView Buttons auton name oeseri o Find a number of locations that have the closest drainage Find area Table 3 MainView Tools area to but do not exceed the user specified area This tool provides many candidate points In order to narrow the number of candidate points the tool should be used when zoomed in to the area of interest Toggle the HEC GeoHMS tools on off When it is in the on position HEC GeoHMS tools are enabled When it is the off position tools from other extensions are enabled e m coe Dere m a e mem ee TEE E oe oe E Tools al mits Trace the flow path downstream of a user F 2 Flow Trace Descriptions i specified point for visualizati n i Pair pees Fe Pont Delineate the watershed contnbunne to a ai Delinente user specified poimi Al Identih Identify contributing area m units as Area specified i thee View s properties distince umi fel Specify Specify the downstream outlet amd or Propect upstream source pomt for extraction of Pit Ferran fore tcen Cc tor This js an ArcView tool that is u ileal i wsefal in
66. ion trial manager Open wizard to create an analysis Select an analysis from list of available analyses Open the analysis manager Check validity of parameters used in the selected simulation run optimisation trial or analysis Compute the selected simulation run optimisation trial or analysis Annexes A61 B Tool bar The followings tools are available under the tool bar reate a new project Open an existing project ave tne current project Print the selected item in the Desktop basin map or result window elect nydrological elements in the basin map Pan in the basin map oom out or decrease the magnitication in the basin map Add a sub basin element to tne basin map Aad a diversion element to the basin map Open time series table tor the current element selection 1 2 Setup an HEC HMS model with inputs from HEC GeoHMS e Start the HEC HMS program e Select File New A62 Resource Manual on Flash Flood Risk Management Module 2 e Browse the location enter the project name and write description optional e Click on Create A new project will be created Creve a hiem Promi atie Mama he aE Dingon a A eg aP jere T Lean Coia H TE cr De mk Li ma rete tre ee Ss oe D el ae pi jT eee pee ee ee el ed ee lia Per a E p Pj A Import basin model e Select File Import Basin Model e Browse the location where the HEC GeoHMS exported model has been saved e Select Basin Model e Sel
67. it 2 Moraines further downstream OOnNDOOAKRWNDN CO no moraines terminal moraine lateral and or medial moraine push moraine combination of 1 and 2 combination of 1 and 3 combination of 2 and 3 combination of 1 2 and 3 debris uncertain if morainic moraines type uncertain or not listed Remarks The remarks can consist of the following information e Critical comments on any of the parameters listed on the data sheet e g how close is the snow line to the firn line comparison of the year concerned with other years e Special glacier types and glacier characteristics that because of the nature of the classification scheme are not described in sufficient detail e g melt structures glacier dammed lakes e Additional parameters of special interest to the basins concerned e g area of altitudinal zones inclination etc e It is often useful to divide the snowline into several sections because of different exposition or nourishment and record the snowline data of each section separately e Literature on the glacier concerned e Any other remarks A104 Resource Manual on Flash Flood Risk Management Module 2 Inventory of Glacial Lakes The glacial lakes identified on the topographic maps as well as on the satellite images like Landsat 7ETM of panchromatic mode and other individual bands and different colour combinations can be delineated and compared with other satellite images The descriptions
68. itation Gauges e Expand the sub basin component e g R420W420 as shown below W Jhiku_runoff l Basin Models B Meteorologic Models e P Jhikhu In Dist a eg Precipitation Sages n R420 420 fee Inverse Distance eet R4s0W430 eet ty Radow4ad Eg RS FOSS i a Control Specifications Node Weights Latitudes Longitudes Name R470W4270 Mode Mame Weight Centroid e Select the Node Weights tab in component editor e Enter anode name and weight value as shown below Note You must always enter a weight for a node The weight controls how the final hyetograph is computed for the sub basin from the hyetographs computed at each node A node can be the precipitation station centroid of sub basin or any given point You need to know the latitude and longitude value of the nodes you create Annexes A75 Components Node Weights Latitudes Longitudes Name R470W420 Node Mame Weigh SE 04 e Select the Latitudes tab and enter the coordinate value e Select the Longitudes tab and enter the coordinate value Components Compute Results Coperta Compute Aeri Node Weights Latitudes Longitudes Horn Weights Latitudes Longibudes Name R420W420 Namir HT Hadr Hame Ca its Miriirs St rs Node Mame Degrees Minutes Seconds a st 04 e Enter the node latitude and longitude values for other sub basin elements in the same way Use the fol
69. lement Time Series Table Element Summary Table E sf a min miu a os ard es a F Boies Pike cult mde fan Cured bigar Bro Creda un Rr ee Piet eerie Haie Pha bs Coal Comune Te DO bee Control Spenar lore re Yoh Ue a aa mieye e a a i i eT Catei hirs TLE m oe oo i E BS oe oe r ra ae ear Le ae oa ne a OG eT Bibh Depta ig T Dii a of Pest De AA e 2 aA p oo aG ce Tobe Peder iiH Teta Perec Ba FLM Sit toe a ee Foral Laia BW Taa ai a0 fH mi w i i a i a l a l A Total Ears Dich 1 H Aue ie e a a be o E ap mii ae ee oa rm a a i Haki i monies A s toga eae tes T ee aa toe Cteersed Habo ph af Gage Gage i divi oh ee oe eo od Peh Concho ges LCS Ceateg Tren of Peat Deechange ra 060 ee oo ne oo oo oe GD aa erg tee Bamia 3 1 Cota a on oe ee SE REO ee Tota Baccus ARIP Tidig 4207 HH 4 e You can display the results for individual elements like the sub basin and junction in the same way A88 Resource Manual on Flash Flood Risk Management Module 2 6 3 Optimisation trial Parameter estimation is the process of adapting a general model to a specific watershed 6 3 1 Creating a new trial e Select Compute Create Optimization Trial e Enter the name or accept the default name e Click Next gt An optimization trial must have a name You can give ita description after it has been created Name Trial 1 To continue enter a
70. llows river beds or on protected slopes developed from snow drifting avalanching and or especially heavy accumulation in certain years usually no marked flow pattern is visible no clear distinction from the snowfield is possible and it exists for at least two consecutive summers 8 Ice shelf A floating ice sheet of considerable thickness attached to a coast nourished by glacier s with snow accumulation on its surface or with bottom freezing Figure 1 1b 9 Rock glacier A glacier shaped mass of angular rock either with interstitial ice firn and snow or covering the remnants of a glacier moving slowly down slope If in doubt about the ice content the frequently present surface firn fields should be classified as glacieret and snowfield Annexes A101 Figure 1 1a Outlet glacier Figure 1 1b Ice shelf Digit 2 Form 1 Compound basins Two or more tributaries of a valley glacier coalescing Figure 1 2a 2 Compound basin Two or more accumulation basins feeding one glacier Figure 1 2b 3 Simple basin Single accumulation area Figure 1 2c 4 Cirque Occupies a separate rounded steep walled recess on a mountain Figure 1 2d 5 Niche Small glacier formed initially in a V shaped gully or depression on a mountain slope Figure 1 2e 6 Crater Occurring in and or on a volcanic crater 7 Ice apron An irregular usually thin ice mass plastered along a mountain slope 8 Group A number of similar ice masses occurr
71. lowing values as an example Sub basin Node name Latitude Longitude name R470W450 rresowaa0 cents 27 es feo jes Ja je R440W440 St 06 5 Defining models and parameter values for hydrological elements Most hydrological elements require parameter data so that the program can model the hydrological processes represented by the element In the case of sub basin elements many mathematical models are available for determining precipitation losses transforming excess precipitation to streamflow at the sub basin outlet and adding baseflow In this document the different mathematical models are referred to as methods The methods available for hydrological elements are shown in Table 9 Parameter data is entered in the component editor Particular sets of parameter data are required for particular models or methods Thus availability of data is one factor determining selection of the model method In this sample exercise we do not have the data required for reach and base flow modelling If no base flow method is applied the sub basin will not compute base flow and the outflow will only include direct runoff from the transform method If no reach method is applied the reach will translate flow instantaneously and without any attenuation HEC HMS User s Manual 2006 The user can select any reach and base flow method if they have the required parameter data A76 Resource Manual on Flash Flood Risk Management Module 2 Table
72. lue triangles The amount of scatter helps to indicate the quality of the parameter estimation e Proceed as above but select Flow Comparison You will see the flow comparison graph Soy To roe ie F Fie Coon e e aT E poisi Te T saw aea a a a aa a a ee kie A i 5i H l i P 1 P f E Compe Fie He Se TT t BH L d 17 SOF E Uire f Ea E m a yum E Flow residuals graph Tr a t ETN F 30 iil O H A w o The flow residuals graph shows the difference between computed and observed flow for each time step It is determined as the computed flow minus the observed flow and may be positive or negative Vertical lines are drawn to show the start and end of the objective function time window The magnitude of the residuals helps to indicate the quality of the parameter estimation The residuals also help to indicate if there are biases in the agreement between the computed and observed flows e Proceed as above but select Flow Residuals You will see the flow residuals graph A94 Resource Manual on Flash Flood Risk Management Module 2 Fipa Faia Fis a F Objective function graph The objective function graph shows the value of the objective function at each iteration of the search method e Pro ies PEH nig PHD foto Deer Bret F u Bor Oiii Fura Era ceed as above but select Object You will see the objective function graph Ip ET
73. m setting in the tools menu as mentioned earlier Annexes A79 Downstrege Cutlets e y Area EMG 1 870000 Lone Method cS Curve Mumbar l Transform Method SES Link Hydrogrash e e Select the Loss tab in component editor e Enter the Curve Number value Leave Initial Abstraction MM blank Optional if Initial Abstraction MM is left blank it will be calculated automatically as 0 2 times the potential retention which is calculated from the curve number The curve number value is shown under the attribute ben in watershd shp that was calculated in HEC GeoHMS in the previous exercise see below e Enter the value of the impervious area in if available for the sub basin Drotial Alot aiiin MP Curve Humber 1 Impervious H T0 IARI M az Oo DST Macha Go rare m iy oo Tay TE iss M ama Ciao TES GSS awe a Tar H AE man n om iT Fala PIE vias S anan 100 arn he mran oar Deo TESA aes Ane UIN TE TET ai m e Select the Transform tab e Enter the Lag Time in minutes Note that the value in the BasinLag column of the attributes table of watershd shp is in hours and that in BasinLag_HMS is in minutes Use the value from the BasinLag_HMS column see attributes table above A80 Resource Manual on Flash Flood Risk Management Module 2 Components Compute Results Subbasin Loss Transform Basin Name Projhk Element Name R420W420 Lag Time M
74. me of the Original unit in map Seismic and the weight value Close the Map window and the Pixel Information window Now you have renumbered the map Seismic into a weight map Wseismic Repeat the same procedure for the maps Landslid Volcanic Tsunami and Beach creating weight maps called Wlandsli Wvolcani Wtsunami and wbeach Now another method will be used to reclassify the maps Inundat River and Topograp You will directly create the weight map using a formula without first storing the weights in a table Type the following formula on the command line of the main ILWIS window Winundat iff Inundat No inundation hazard 0 5 d In the Raster Map Definition dialogue box select the domain Value with values range between 0 and 5 and a precision of 1 0 Click OK No calculation takes place yet Only the definition is stored and a raster map icon for the map Winundat is made The actual calculation takes place only after opening the map Double click raster map Winundat The map is calculated before the Display Options dialogue box is opened Select the representation Pseudo and click OK Design the formula for creating the map Wriver yourself All classes of the input map River will get the value of 4 except for the class No river which gets 0 Also make the map Wtopogra in which all classes of the input map Topograp will get the value of 2 except for the class Altitude less than 1000m which gets 0 Make
75. minimise their personal threat of loss or damage Local communities should be sufficiently familiar with the hazards to which they are exposed and understand advisory information received to be able to act to advise instruct or engage the population in a manner that increases their safety or reduces the possible loss of resources on which the community depends National governments should exercise sovereign responsibility to prepare and issue hazard warnings for their national territory in a timely and effective manner and to ensure that warnings and related protective guidance are directed to those populations determined to be most vulnerable to the hazard risk The provision of support to local communities to utilise information and to develop operational capabilities is an essential function to translate early warning knowledge into risk reduction practices Regional institutions should provide specialised knowledge advice or the benefit of experience in support of national efforts to develop or sustain operational capabilities related to hazard risks experienced by countries that share a common geographical environment Regional organisations are crucial to linking macro scale international capabilities to the particular needs of individual countries and in facilitating effective early warning practices among adjacent countries International bodies should provide means for the shared exchange of data and relevant knowledge among themselve
76. moisture soil groundwater storage percolation accounting loss coefficient maximum infiltration mm hr impervious area tension storage soil percolation mm hr Clark unit Time of concentration storage coefficient hydrograph Conceptual plane length slope roughness coefficient Kinematic wave percentage of sub basin area occupied by plane area bottom shape side slope Modclark Time of concentration storage coefficient Transform ool Lag time min hydrograph Snyoer uai Standard lag hr peaking coefficient hydrograph User specified S graph Lag time hr S graph User specified unit hydrograph Payer eg rapn Annexes AT eonnaed Initial discharge recession constant base flow for a January to April base flow onaran Monthly base flow January to July monthly Base flow Linear Ground water storage initial discharge and reservoir coefficient Nonlinear Initial discharge flow ratio subsurface length boussinesq conductivity porosity Initial discharge recession constant base flow Recession aio Kinematic Reach element length slope Manning s n laa bottom width side slope Modified plus omen oe discharge function elevation discharge unction Muskingum k travel time through the reach Routing Muskingum Muskingum x weighting between inflow and Reach outflow influences i Reach element length slope Manning s n Muskingum bottom width side slope or left cross section c
77. n a series of marked steps with some crevasses and seracs Ice fall A glacier with a considerable drop in the longitudinal profile at one point causing a heavily broken surface Interrupted Glacier that breaks off over a cliff and reconstitutes below Digit 5 Major source of nourishment The sources of nourishment could be uncertain or miscellaneous 0 snow and or drift snow 1 avalanche and or snow 2 or superimposed ice 3 as indicated in Table 3 Digit 6 Activity of tongue A simple point qualitative statement regarding advance or retreat of the glacier tongue in recent years if made for all glaciers on earth would provide the most useful information The assessment of an individual glacier strongly or slightly advancing or retreating etc should be made in terms of the world picture and not just that of the local area However it seems very difficult to establish a quantitative basis for assessing tongue activity A change of frontal position of up to 20m per year might be classed as slight advance or retreat If the frontal change takes place at a greater rate it would be called marked Very strong advances or surges might shift the glacier front by more than 500m per year Digit 6 expresses annual tongue activity qualitatively If observations are not available on an annual basis then an average annual activity is given Moraines Two digits to be given Digit 1 Moraines in contact with present day glacier Dig
78. name and click Next fd e lf you have created more than one simulation run then select the desired run e Click Next gt An op mirahon taal mugi be haced on an seisding simulation nun concaining at inant one element eth cteaennd tow Boled a run fmm the fst below An ee auia parame bangi pn pipereed Mra al a F kjer barin Pem t Heimi on Permien fom he fs heiim Cee an eel d ki miih To contnun select a rman and click Mee ase STED a lack Fush Cancel Batk ET Cancel e Select an element where there is observed flow If there are many observed flows as in this case then you can create different optimisation trials and select different elements in each For example in the following we select Outlet_A the most downstream outlet in the study basin e Click Finish Annexes A89 B Selecting the optimisation run e Select Optimization Trial folder to expand it C Jhiku_runoff Simulation Runs A currenti 2 Optimization Trials a w 1 e Select the Compute tab in Watershed Explorer e Select Univariate Gradient under Method e Twosearch methods are available for minimising the objective function and finding optimal parameter values The univariate gradient method evaluates and adjusts one parameter at a time while keeping other parameters constant The Nelder Mead method uses a downhill simplex to evaluate all parameters simultaneously and determine which parameter to adjust T
79. nd moraine lakes and lateral moraine lakes e blocking lakes formed through glaciers and other factors including the main glacier blocking the branch valley the glacier branch blocking the main valley and the lakes formed through snow avalanche collapse and debris flow blockade e ice surface and sub glacial lakes Annexes A105 In the glacial lake inventory end moraine dammed lakes lateral moraine lakes trough valley lakes glacial erosion lakes and cirque lakes are represented by the letters M L V E and C respectively B represents blocking lakes Activity According to their stability glacial lakes are divided into three types stable potential danger and outburst when there have been previous bursts The letters S D and O respectively represent these types Types of water drainage Glacial lakes are divided into drained lakes and closed lakes according to their drainage condition The former refers to lakes from which water flows to the river and joins the river system In the latter water does not flow into the river Ds and Cs represent those two kinds of glacial lakes respectively Chemical properties This attribute is represented by the degree of mineralisation of the water mg 1 Other indices One important index for evaluating the stability of a glacial lake is its contact relation with the glacier Therefore the distance from the upper edge of the lake to the terminus of the glacier has been added and the code
80. nt pane The Display Options Raster Map dialogue box is opened Select Representation Clrsto12 and click OK The map is now displayed with a Representation Clrstp12 3 Creating Flood Scenarios Flood scenario maps for different return periods can be generated using the DEM You can use the results generated from the flood frequency analysis An example of maximum magnitude in metres for different flood return periods is given below Annexes A15 Return period years Flood level m T a o w o Note In this simplified exercise the flood level over the whole study area is taken as constant In reality flood levels vary with location particularly in the case of a flash flood Creating a 1 year flood domain From the File menu in the Main window choose the Create Domain command From the Create Domain dialogue box type 1 Year Flood as the domain name Click the Group check box to select domain type as group domain Accept all the other defaults and click OK From the Domain Group Editor click Add item and the Add Domain Item dialogue box opens Enter Upper bound as 18 Enter Name as 1 Year Flood and click OK Creating a 1 year flood map To create a 1 year flood map you have to extract the area contour height less that 18 metres For this you have to use the Slicing operation in ILWIS From the Operation menu select Image Processing and then Slicing From the Slicing dialogue box select the Rast
81. nuation Channel losses can be included optionally in the routing calculated by summing all inflows x The source element is used to introduce flow The source element has no inflow Outflow Source rom the source element is defined by the user t Junction The junction is used to combine streamflow from elements located upstream of the ap junction Inflow to the junction can come from one or many upstream elements Outflow is The sink is used to represent the outlet of the physical watershed Inflow to the sink can come from one or many upstream elements There is no outflow from the sink Annexes A65 Reservoir The reservoir is used to model the detention and attenuation of a hydrograph caused by a reservoir or detention pond Inflow to the reservoir element can come from one or many upstream elements Outflow from the reservoir can be calculated using one of three routing methods The diversion is used for modelling streamflow leaving the main channel Inflow to the s diversion can come from one or many upstream elements Outflow from the diversion element consists of diverted flow and non diverted flow Diverted flow is calculated Diversion using input from the user Both diverted and non diverted flows can be connected to hydrological elements downstream of the diversion element D Program setting e Select Tools Program Settings e In General tab check automatically open last project on start up Brow
82. o observational data and other warning information between countries particularly when hazardous conditions affect neighbouring countries Timely accurate and reliable warnings should be understood in the context of commonly accepted international standards nomenclature protocols and reporting procedures Established or internationally agreed means of communications should be employed for the international and regional dissemination of any warning information to specific authorities designated in each country Collaboration and coordination is essential between scientific institutions early warning agencies public authorities the private sector the media and local community leaders to ensure that warnings are accurate timely meaningful and can result in appropriate action by an informed population Resource Manual on Flash Flood Risk Management Module 2 Annex 4 Runoff Curve Numbers Type of Land Cover Runoff Coefficients Agricultural Land Bare packed soil Cultivated rows Pasture Woodlands Annexes Heavy soil no crop 0 30 0 60 a ee T A23 Annex 5 Training Manual on Flash Flood Modelling using HEC GEOHMS and HEC HMS d h Acmon YSAID A24 Resource Manual on Flash Flood Risk Management Module 2 Preface Flash flood management is very important in the Hindu Kush Himalayas as flash floods are one of the most damaging water induced hazards in the region Flash flood modelling is a
83. of attributes for the glacial lakes inventory are based on LIGG WECS and NEA 1988 Similar methodology was used to inventory the glacial lakes of Nepal and Bhutan Mool et al 2001a and b Tista basin Sikkim India Astor basin Pakistan and Pumau basin Tibet Autonomous Region PR China ICIMOD 2007 as given below Numbering of glacial lakes The permanent snowline in the northern belt of the Himalayas is higher than 4 000 masl All the glacial lake boundaries are demarcated by screen digitising in the georeferenced satellite image of Landsat 7ETM of panchromatic mode The global climatic change during the first half of the 20 Century had a tremendous impact on the high mountainous glacial environment Many of the big glaciers melted rapidly and gave birth to a large number of glacial lakes Due to the faster rate of ice and snow melting possibly caused by global warming the accumulation of water in these lakes has been increasing rapidly The isolated lakes above 3 500 masl are assumed to be the remnants of the glacial lakes left due to the retreat of the glaciers The attributes used for the present inventory are similar to the lake inventories that were done in the Pumau Arun and Poiqu Bhote SunKoshi basins in Tibet LIGG WECS NEA 1988 Nepal and Bhutan by ICIMOD in 2001 Pumaqu basin Tibet Autonomous Region PR China Astor basin Pakistan and Tista basin Sikkim India 2003 The numbering of the lakes starts from the
84. old type from the dropdown list as Area in Distance Units squared e Click OK Select the threshold type for stream initiation Area in Distance Units squared i Cancel e Accept the default value for the threshold for stream initiation The default is one percent of the largest drainage area in the entire basin The smaller the threshold chosen the greater the number of sub basins delineated by Geo HEC HMS If desired by the user the value can be defined according to the project need instead of accepting the default value e Click OK e Click OK again You can zoom in to display the detail of the grid cells that make up the stream definition grid Annexes A37 E Stream segmentation Stream segmentation divides the stream into segments Stream segments of links are the sections of a stream that connect two successive junctions a junction and an outlet or a junction and the drainage divide e Select Terrain preprocessing Stream Segmentation e Confirm that the input of FlowDirGrid is fdirgrid and of StreamGrid is strgrid The output of the LinkGrid is StrLnkGrid StrLnkGrid is a default name that can be renamed by the user e Click OK e Click OK F Watershed delineation This step delineates a sub basin or watershed for every stream segment e Select Terrain preprocessing Watershed Delineation e Confirm that the input of the FlowDirGrid is
85. oraine dam has a combination of the following characteristics narrower in the crest area no drainage outflow or outlet not well defined steeper slope of the moraine walls ice cored very tall from toe to crest mass movement or potential mass movement in the inner slope and or outer slope breached and closed in the past and refilled with water seepage flow at moraine walls A moraine dammed lake that has breached and closed subsequently in the past and has refilled with water can breach again Nagma Pokhari Lake in the Tamor Basin burst out in 1980 The study of recent aerial photographs and satellite images shows a very quick regaining of lake water volume Zhangzangbo Lake in the Sun Koshi Basin the Poiqu Basin in Tibet burst out in 1964 and again in 1981 Recent satellite images show that the lake has refilled with water and therefore could pose danger Ayaco Lake in the Pumau Basin in Tibet burst out in 1968 1969 and 1970 and at present it is refilled with water and poses danger Regular monitoring of such lakes using multi temporal satellite images is necessary Condition of associated mother glacier Generally the bigger valley glaciers with tongues reaching an elevation below 5 000 masl have well developed glacial lakes Even the actively retreating and steep hanging glaciers on the banks of lakes may be a potential cause of danger The following general characteristics of associated mother glaciers can create danger to moraine
86. p generated in the previous exercise can be used to create flood zonation maps Use the following table to get the flood magnitudes for different flood Zones High risk zone map creation From the File menu in the Main window choose the Create Domain command From the Create Domain dialogue box type HRzone as the domain name Click the Group check box to select domain type as group domain Accept all the other defaults and click OK From the Domain Group Editor click Add item and Add Domain Item dialogue opens Enter Upper bound as 22 Enter Name as High Risk Zone and click OK Annexes A17 From Operation menu select mage Processing and then Slicing From the Slicing dialogue box select the Raster map Dem Type HRzone as Outout Raster Map Select HRzone as domain Type High Risk Zone as the description Click Show to generate the map From the Operations menu select Raster Operations and click Cross The Cross dialogue box opens Select HRzone as the 1 Map Select Wards as the 2 Map Type HRzone_ww for the Outout Table name Type 1 year ward wise flood map as the description Click the Output Map check box to select and type HRzone_ww as the output map name Click Show to generate the map Apply the same procedure to generate the Moderate Risk Zone map and Low Risk Zone map By using Histograms of each map area calculations can be performed A18 Resource Manual on Flash Flood
87. past although the mechanisms at play are not fully understood Criteria for Identification The criteria for identifying potentially dangerous glacial lakes are based on field observations processes and records of past events geomorphological and geo technical characteristics of the lake and surroundings and other physical conditions The potentially dangerous lakes were identified based on the condition of lakes dams associated mother glaciers and topographic features around the lakes and glaciers Rise in lake water level In general the lakes exceeding 0 01 km in volume are found to have had past events A lake with a larger volume than this is that deeper with a deeper part near the dam the lower part of lake rather than near the glacier tongue and that has rapid increase in lake water volume is potentially dangerous Activity of supra glacial lakes Groups of small closely spaced supra glacial lakes at glacier tongues merge as time passes and form bigger lakes such as Tsho Rolpa Glacial Lake which is associated with many supra glacial lakes in the topographic map of 1974 The merging of supra glacial lakes into the Tsho Rolpa Glacial Lake has formed a bigger lake in the topographic map of 1981 aerial photograph of 1992 and topographic map of 1996 Some new lakes of considerable size are also formed at glacier tongues such as the lake at Lower Barun Glacier The lake is neither visible in the topographic map published by the S
88. pect hazard In later exercises you will evaluate the vulnerability and finally the risk The degree of hazard of a certain area is determined by a combination of factors The different factors that influence the degree of hazard can be observed separately although they influence each other e g in an area with high seismic hazard there will be more landslides The factors are provided in the form of parameter maps each of them describing a potentially damaging phenomenon The following phenomena are taken into account landslide hazard seismic hazard tsunami hazard earthquake induced flood waves volcanic hazard flood hazard erosional hazard by torrential rivers beach erosion and accretion hazard topographic regions In the previous section you have seen the spatial distribution of the various hazards in Colombia The next step is to combine this information into one map You can follow two approaches e Simply sum up all the maps with equal weight or e Assign different weights to different hazard types In this exercise you will follow the second approach The impact of the different hazards on human activity is not equal for all types of hazard A strong earthquake will have a much more devastating effect on an area than a landslide Therefore you have to assign weights to each of the classes within the individual hazard maps taking into account their importance in producing the image The weight given to a certain factor and
89. ram will delineate sub basins at those locations but without interaction to view and revise This menu is used for developing the physical characteristics of streams and sub basins based on the terrain model The characteristics of the stream and sub basin are stored in the respective attribute tables This menu is used to process and estimate a number of hydrological parameters like loss rate parameters time of concentration basin slope and others This menu performs a number of tasks related to HMS These tasks include assigning default names for the reaches and sub basins unit conversion checking and creation of the basin schematic and HMS file generation This menu contains miscellaneous tools assigning roles for data sets and developing graphical output It provides the capability to prepare a curve number CN grid based on a soil and landuse database Resource Manual on Flash Flood Risk Management Module 2 Table 5 ProjView Buttons Name Description o Find area Same as those in the MainView gm ee Saneas moseinheManview Toggle GeoHMS Same as those in the MainView Table 6 ProjView Tools Too name pescon o Identify area Same as those in the MainView FR Basin subdivide Subdivide existing basin or create new basin at user specified point outlet l Profile Extract the stream profile with elevation based on the terrain model Batch point Create a batch point shape files layer based on the user specif
90. ream confluence e Select Terrain preprocessing Watershed Aggregation e Confirm that the input of River is River shp and of Watershed is Wshedshp shp The output of AggregatedWatershed is WshedMg shp WshedMg shp is a default name that can be renamed the user e Click OK e Click OK again Povas mae oO Watershed hedro sho fager mer thend ia heg sho woe cms A40 Resource Manual on Flash Flood Risk Management Module 2 3 3 Hydrological model setup In this step the watershed is defined 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 e Add the hydrological station location theme hydro_gage shp to the MainView to help determine the outlet location e Make the hydro_gage shp active and identify the Lower Andheri Khola gauge station id 2 e The identified gauge has a drain area of about 5 390 sq km e Zoom in on the gauge and make the strinkgrid theme visible e Use the E tool and click on the grid cell with the identified gauge The grid cell has 5 399 sq km of drainage area The result is The area is 5 3996 kilometers squared shown in the lower left corner This cell has a drainage area that is sufficiently close to that of the gauge Wore e Select HMS Project Setup Start New Project e Enter ProJhk as the project name e
91. roduce a vulnerability map The weight values that will be used in this exercise are based upon the relative importance of each of the elements at risk with respect to the damage caused by a disaster In reality these vulnerability values will be different for different hazard types For example the vulnerability of roads to inundation is less than to landslide or earthquake as during a flood roads are only temporarily unuseable whereas during landslides or earthquakes they may be partly destroyed We have not taken this aspect into account here The following weight values are used Concentr Legend 5 low S O O Industry Pipeline SE E No vulnerability O0 Infraseg City 10 Manoa oS o e O Rawy O o e O No vulnerability 0 Popdens Legend lt 1 person km 1 20 persons km 20 50 persons km gt 50 persons km A10 Resource Manual on Flash Flood Risk Management Module 2 As the calculation of the vulnerability map is very similar to the calculation of the hazard map not all of the individual steps are explained in detail All steps are combined below Create tables for the maps Industry Concentr and Infraseg and fill in the weights Create weight maps using the maps Industry Concentr and Infraseg and the tables you have just made The resulting maps are called Windustr Wconcent and Winfras Create weights for population density in the table Colombia using the values in the table on the previou
92. s ShLength length of TR55 shallow flow overland flow and so on in the attributes table of longestfp shp D Time of concentration and lag time computation A52 Open the Excel file tc xls located at AV_GIS30 ARCVIEW ETC Enable the macro option if disabled in Excel file In arc view project select Hydrologic Parameters TR55 Export Tt Parameters to Excel Open tc xls Update Manning s Roughness Coefficient value in the Excel file as shown in the following figure To derive the Manning s n value for each sub basin use the overlay operation in Arc View Arc GIS between mannin_n and watershed shp Click on Calculator button amp T755 e2 to export the travel time back to HEC GeoHMS Resource Manual on Flash Flood Risk Management Module 2 e Click OK in Arc View 1 Worksheet for computation of time of travel according t TR 55 petilodolosy Pz H H d Wihee and yellow calculated Red final tewult E m FE j m m Se ee E E E Proh 0807 1824 x05 Gaa Oe RE IAS a ahah RAEI seen e ji nja The computed basin lag time hr and travel time hr will be saved in the attributes of watershed shp as shown below ar an Ea anae S r riia Pa om A TA Le nj ash Fh iL ASE 0 000 0000 omg ra Thr TI FEL ISIS TAS ee Ome saa ae aman M owm DN TAS PFF cao cee ito ga Ga sem me Fl emi ROTA GESS a ia mad nian 5 3 Develop HMS inputs
93. s as a basis for the efficient transfer of advisory information and the technical material and organisational support necessary to ensure the development and operational capabilities of national authorities or agencies officially designated as responsible for early warning practice Principles for the Application of Early Warning at National and Local Levels A20 Early warning practices need to be a coherent set of linked operational responsibilities established at national and local levels of public administration and authority To be effective these early warning systems should themselves be components of a broader programme of national hazard mitigation and vulnerability reduction Within each country the sole responsibility for the issuance of early warnings for natural and similar disasters should rest with an agency or agencies designated by the government The decision to act upon receipt of warning information is political in character Authoritative decision makers should be identified and have locally recognised political responsibility for their decisions Normally action resulting from warnings should be based on previously established disaster management procedures of organisations at national and local levels Resource Manual on Flash Flood Risk Management Module 2 10 In the chain of political responsibility initial hazard information is often technically specialised or specific to a single type of hazard authority
94. s page Create the weight map Wpopdens by reclassifying the map Colombia with the reclassified population densities Combine the four weight maps Windustr Wconcent Winfrase and Wpopdens by adding them up The resulting map is called Vulnerab Create a class group domain Vulclas with 4 classes Very low vulnerability Low vulnerability Moderate vulnerability High vulnerability Classify the map Vulnerab into 4 classes using the operation slicing The result is called VulCclas Display the result and make a representation and annotation At this point you have a hazard map and a vulnerability map and now you can combine them into the final risk map 4 Creating the Risk Map The final stage in a risk analysis is the creation of a risk map Risk can be defined as the expected degree of loss due to particular natural phenomena In a real project this would be the multiplication of costs x vulnerability x recurrence interval of natural damaging phenomenon We do not dispose of cost data nor of recurrence intervals in this simple example Therefore you will simplify the procedure by calculating the risk as the combination of natural hazard and the vulnerability You will make a qualitative risk map giving the general relationship between hazard and vulnerability The combination will be done using a two dimensional table In the Main window select File Create Create 2 Dimensional Table Enter the Table Name Risk Select H
95. se the project directory e In General tab you can check the options on or off like displaying a warning before changing or deleting the component method showing tooltips etc e Similarly you can choose different settings for results and message under the Result and Message tabs You can also leave the default options e Click OK a Program Settings eal A Display warning before changing component method Display warning before deleting a component Show tooltips on compute tab in watershed explorer Use description For tooltip Use components For tooltip Optimize For minimum memory usage Automatically open last project on start up Project Directory usample PROIHE Jhiku_runott ok Cancel A66 Resource Manual on Flash Flood Risk Management Module 2 2 Control specifications Control specifications are one of the main components in a project even though they do not contain much parameter data Their principle purpose is to control when simulations start and stop and what time interval is used in the simulation A Creating control specifications e Select Components Control Specifications Manager e Click New e Write the name and description e Click Create Create 4 Mew Contel Speideeteens Pare ee ee Deron Pe ree SS ee Gr ihe ore of ee epee vere fe DIALA m a La B Setting the time window e Select Components ta
96. sent day glaciers and the downstream banks are usually made of bedrock or covered with a thinner layer of loose sediment Neither of these types generally poses an outburst danger On the other hand moraine dammed glacial lakes have the potential for bursting No standard index to define a lake that is a source of potential danger because of possible bursting exists Moraine dammed glacial lakes which are still in contact or very near to the glaciers are usually dangerous Most of the literature uses the term glacier lake for such lakes and the term glacial lakes for glacier erosion lakes and glacier cirque lakes The present study defines all the lakes formed by the activity of glaciers as glacial lakes Moraine dammed glacial lakes are usually dangerous These lakes were partly formed between present day glaciers and Little Ice Age moraines The depositions of Little Ice Age moraines are usually about 300 years old form high and narrow arch shaped ridges usually 20 150m high and often contain dead glacier ice layers beneath them These end moraines are loose and unstable The advance and retreat of the glacier affect the hydrology between the present day glacier and the lake dammed by the moraines Sudden natural phenomena that directly effect a lake like ice avalanches or rock and lateral moraine material collapsing on a lake cause moraine breaches with subsequent lake outburst events Such phenomena have been well known in the
97. sure not to make a typing mistake in the long name otherwise the result will be undefined Now you have all the weight maps ready A6 Resource Manual on Flash Flood Risk Management Module 2 Step 3 Combining the weight maps The next step in the creation of the hazard map is the combination of the individual weight maps ee e Type the following formula on the command line Hazard Wseismic Wlandslit Wvolcani Wbeach Wtsunamit Wriver Winundat Wtopograd Click OK in the Raster Map Definition dialogue box Display the map Hazard Use the Pseudo representation Use the pixel information window to read the values of the input maps together with those of the map Hazard Check if the computer can add up values correctly Close the map window and the pixel information window Step 4 Classifying the hazard map The hazard map which was made in the previous section has many different values The range of values can be evaluated by calculating a histogram In the Main window select the following menu items Operations Statistics Histogram Select the map Hazard and click OK The histogram is calculated and the result shown in a table In the Table window select the menu items Options Show Graph The Graph dialogue box is opened Select Value for the X axis and Npix for the Y axis and click OK The Edit Graph dialogue box is opened Select Line and click OK The histogram will be shown on the screen Evaluate the values
98. ter under Parameter using the dropdown menus Select the default value under initial value This is the starting point for the parameter estimation process The search method will begin the search for optimal parameter values from this point The default value is the value in the corresponding basin model in the underlying simulation run You may change the initial value without affecting the basin model e Select No under Locked from the dropdown menu When a parameter is locked the initial value is used and no adjustments are made during the search process e f desired assign minimum and maximum values for the search optimisation value Comprens Compute Recut Hj Optimization trial Parameter Mante Trial I Elenak Papyan Pian ares Cr haia e You can add further parameters adding more elements or only one element in the same way to estimate the optimised value 9 Jhiku_runatF Sy Simulation Runs 5 2 Optimization Trials igy Trial 1 Objective Function Parameter 1 I5 Parameter 2 bi Parameter 3 D Computing a trial e Select Compute Compute trial e Wait it may take several minutes e When finished click Close Baan Prod Meo Fa ln Get Cordal Je PFI A92 Resource Manual on Flash Flood Risk Management Module 2 6 3 2 Viewing the trial results A Objective function table The objective function table provides summary information about the objective function at the evaluation location
99. the project is saved xi Fire E HA Criar pai e Click OK The result of the fill sinks operation is the Fillgrid theme the lowest cell elevation is increased from 790 to 798 metres A34 Resource Manual on Flash Flood Risk Management Module 2 B Flow direction This step defines the direction of the steepest descent for each terrain cell Similar to compass the eight point four algorithm specifies the possible direction as 1 east 2 southeast 4 south 8 southwest 16 west 32 northwest 64 north and 128 northeast e Select Terrain preprocessing Flow Direction e Confirm that the input of the HydroDEM is Fillgrid The output of the FlowDirGrid is FdirGrid FdirGrid is a default name that can be renamed by the user e Click OK e Click OK in Flow direction computation message box Te BETIS ce 277 8 eh aad 2 1 el EL hy EEQ 855 Eii EI pn 1 te 17I oe It TI A i O g C Flow accumulation This step determines the number of upstream cells draining to a given cell The upstream drainage area at a given cell can be calculated by multiplying the flow accumulation value by the cell area e Select Terrain preprocessing 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 re named by the user e Click OK e Click OK in the m
100. the relationship H 11 32 53 21 F 0 3 where H is ice thickness and F is glacial area e Open attribute table Rol_gr The column area_km contains the area of glaciers in km e Type the following formula on the command line Thickness 53 21 pow area_km 0 3 11 32 d 3 This calculation derives the ice reserve in the glacier in km e Open attribute table Rol_gr The column area_km contains the area of glaciers in km e Type the following formula on the command line Tce reserves Thickness 1000 area km J 4 This is to find glaciers larger than 10 km in area Big_gr area_km gt 10 4 5 The following syntax is used to find glaciers having accumulation area in south and ablation area towards north west direction S then NW orien_acc S8 and orien_abl NW Jd 6 This is to find glaciers bigger that ten km in area and flowing towards SW and NW directions BigSW_and_NW iff orien_abl SW or orien_abl NW and area_km gt 10 K 2 dH 7 To find glaciers not flowing south Gr_abl_ not_S iff orien_abl lt gt S Orien_abl ablation in S direction a 8 To find glaciers having ablation categorised grouped as type if ablation area is towards south direction South_class iff orien_abl lt gt S orien_Abl typel 4 9 This is to show an example of ILWIS syntax to calculate which glaciers may retreat with the assumption that fast retreat may be havin
101. the way this factor is classified are highly subjective This method is also referred to in the literature as blind weighting as we do not dispose of quantitative data to decide whether the relationship between high seismic hazard and high landslide hazard should be 1 or 10 or 100 The expert s opinion is used to define these weights Hence nearly every scientist may assign a different value Later on the weight values will be used instead of the map values In this way the separated parameter maps of the factors involved in the hazard analysis become weighting maps This exercise consists of several steps Step 1 Assigning weight values to the classes of the parameter maps The weight values will be assigned in tables connected to the raster maps Create a table for each map and then create a column weight in which you will edit the weight values for the different classes Annexes A3 Step 2 Renumbering the parameter maps to weight maps The combination of each parameter map with the weight values derived from the table created in the previous step is called renumbering In this way you will change the maps with classes into value maps with weight values Step 3 Combining the weight maps into one single hazard map The weight maps will be combined in this exercise by simply summing them It is also possible to assign weights to the individual maps For example the weight given to seismic hazard can be two times that for landslide ha
102. to those individuals at risk and ultimately for facilitating appropriate community actions to prevent loss and damage A high resolution of local knowledge and developed experience of local risks decision making procedures definitive authorities concerned means of public communication and established coping strategies are essential for functions to be relevant Groups of people that exhibit different types of vulnerability will have different perceptions of risk and various coping strategies Locally appropriate warning systems will provide a range of communication methods and should provoke multiple strategies for protection and risk reduction To be sustainable all aspects of the design and implementation of early warning systems require the substantive involvement of stakeholders at the local and national levels This includes production and verification of information about perceived risks agreement on the decision making processes involved and standard operational protocols Equally important abilities involve the selection of appropriate communication media and dissemination strategies which can assure an effective level of participation in acting upon receipt of warning information Principles for Early Warning Systems at International and Regional Levels Annexes In the interest of concerted international efforts to reduce the adverse effects of natural and similar disasters the technologically advanced countries have an obli
103. ts Delineation of visible ice firn and snow from rock and debris surfaces for an individual glacier does affect various inventory measurements Marginal and terminal moraines are also included if they contain ice The inactive ice apron which is frequently found above the head of the valley glacier is regarded as part of the valley glacier Large perennial snow patches are also included in the inventory Rock glaciers are included if there is evidence of large ice content Snow line In the present study the snow line specially refers to the firn line of a glacier not the equilibrium line The elevation of the firn line of most glaciers was not measured directly but estimated by indirect methods For the regular valley and cirque glaciers shown on topographical maps the snow line was assessed by Hoss s method i e studying changes in the shape of the contour lines from convex in the ablation area to concave in the accumulation area Accuracy rating table The accuracy rating table proposed by Muller et al 1977 on the basis of actual measurements Table 1 is used For the snow line an error range of 50 100m in altitude is entered as an accuracy rating of 3 In the glacier inventory different methods or a combination of methods are usually chosen for comparison with satellite images in order to assess the elevation of the firn line for different forms of glacier A98 Resource Manual on Flash Flood Risk Management Modul
104. tware for the Inventory of Glaciers and Glacial Lakes and to Identify the Potentially Dangerous Glacial Lakes Getting Started The data for this case study are stored together with this annex on the CD ROM in the directory Annex_ Vi_GlacialLake Attribute Data Copy the data to your hard drive at an appropriate location Double click the ILWIS program icon in the ILWIS program group Change the working drive and the working directory until you are in the data directory Visualisation of the Data Before you can start with the actual analysis it is important to have an idea of the input data Open and check following files Soi_rol Coordinate projection system Realgar Polygon map of glaciers Rol_gl Polygon map of glacial lakes Area_cl Domain file for classifying glacier according to their areas CONS_SOI Contour map of Rolwaling area DEM_IN_M Digital Elevation Model Rolwaling area There are other files in the folder You may open these files and visualise as well A110 Resource Manual on Flash Flood Risk Management Module 2 Syntaxes related to handling of glacier attribute data ee 1 This syntax is to find the location in geographic coordinate system in latitude and longitude from the coordinate system as defined in Survey of India Maps of Rolwaling Area e Type the following formula on the command line Latitute_Longitude transform coord x y soi_rol latlon J 2 This syntax is to find the thickness of a glacier using
105. u e Select None for Evapotranspiration and Snowmelt 9 Huut a G roth E i epii Cages Cahirad Doeciicahors i j Time Seis Dat eae ae Corpute Results Se Of Meheorsiogy Model Benin Dobora Gescrintion Meberokeical model using inversar f Prepa leria Detance Crier anion hone Great Eii Lit Sten Bara HEHE e Select the Basins tab in the components editor e Select Yes in Include Subbasins options Components Compute Brads Stare ikha im Dirt e Select the Options tab e Select Yes in Replace Missing and define the Search KM as the search distance for the inverse distance operation Components Camna Rea 2 Metrorndegy Haii Bran phos Mares Deiklwa bn Dist Reploce Mirci lis Deeded Ma Search KM 25 A74 Resource Manual on Flash Flood Risk Management Module 2 e In Watershed Explorer under the Meteorological Models component select Precipitation Gauges e Select Components Time Series Gages e Select Yes for Use Gauge and No for Daily Gauge 9 Jhiku_runoff E E Basin Models a Meteorologic Models i Jhikhu In Dist ooo in eam Precipitation Gages H fie Control Specifications f y Time Series Data Components Time Series Gages Mame Jhikhu In Dist Gage Mame Lise Gage Daily Gage St 04 st 06 e In Watershed Explorer go to Meteorological Models Precip
106. unge routing graph Straddle Lag time duration amount of spreading in a flood stagger peak as it travels through the reach Flow rate fraction Loss gain Considering the data availability and simplicity we will use the SCS Curve Number Loss in the loss method and SCS Unit Hydrograph Transform in the transform method for the sub basin A78 Resource Manual on Flash Flood Risk Management Module 2 5 1 Program options e Select Tools Project Options e Select the SCS Curve Number in Loss SCS Unit Hydrograph in Transform None in Baseflow and Routing Inverse Distance in Precipitation and None in Evapotranspiration and Snowmelt options using the dropdown menus as shown below e Click OK Project Opbers eku unet ak Che aks Lial dylem airig Lsi 5 Curve kumis Trarefonm sens ung Hakea Bisset beet pire raai E ea Praaptbboi roe ne Dista Ceara area tO eh E SPOOR pera 5 2 Selecting methods and assigning parameters to hydrological elements A Sub basin e Inthe Watershed Explorer window go to Basin Models e Expand the project name as shown below e Select the sub basin element component e g R420W420 e In the sub basin editor select SCS Curve Number in Loss Method SCS Unit Hydrograph in Transform Method and None in Baseflow Method from the dropdown menus Ignore any warning message You can turn off warning messages from the progra
107. ure and field measurements Annexes A99 Table 2 Relationship between glacier type form area and depth as given by Muller et al 1977 Glacier type Form Area km mn i Compound basins Valley glacier Compound basins Mountain glacier Area of the glacier The area of the glacier is divided into accumulation area and ablation area the area below the firn line given in square kilometres The delineated glacier area is digitised in the integrated land and water information systems ILWIS format and the database is used to calculate the total area Length of the glacier The length of the glacier is divided into three columns total length length of ablation and mean length The total maximum length refers to the longest distance of the glacier along the centreline Mean width The mean width is calculated by dividing the total area km by the mean length km Orientation of the glacier The orientation of accumulation and ablation areas is represented in the eight cardinal directions N NE E SE S SW W and NW Some of the glaciers cap only in the form of an apron on the peak which is inert and sloping in all directions and is represented as open The orientations of both the areas accumulation and ablation are the same for most of the glaciers Elevation of the glacier Glacier elevation is divided into highest elevation the highest elevation of the crown of the glacier mean elevation the
108. urvey of India in 1967 nor in the topographic map published by Nepal Kartenwerk der Arbeitsgenmeinschaft fur vergleichende Hochgebirgsforschung Nr 2 in 1974 The lake is distinct and large in the topographic map of 1996 published by the Department of Survey Nepal These activities of supra glacial lakes indicate that the lakes are becoming potentially dangerous Annexes A107 Position of lakes The potentially dangerous lakes are generally at the lower part of the ablation area of the glacier near the end moraine and the mother glacier should be sufficiently large to create a potentially dangerous lake environment Regular monitoring needs to be carried out for such lakes with the help of multi temporal satellite images aerial photographs and field observations In general the potentially dangerous status of moraine dammed lakes can be defined by the conditions of the damming material and the nature of the mother glacier Valley lakes with areas exceeding 0 1 km and a distance less than 0 5 km from a mother glacier of considerable size are considered to be potentially dangerous Cirque lakes even smaller than 0 1 km associated in contact or distance less than 0 5 km with steep hanging glaciers are considered to be potentially dangerous Even a smaller steep hanging glacier may pose a danger to the lake Dam conditions The natural conditions of the moraine damming the lake determine the lake stability Lake stability will be less if the m
109. used to determine what required parameters are missing or what specified parameters have invalid values All messages are shown in the message window at the bottom of the program screen regardless of when or how they were produced D Computing a run e Select Compute Compute run Current1 Or e Right click mouse button on simulation run Currenti in Watershed Explorer and click on Compute e Wait for some time the program will compute the run When finished click Close Finithed Computing Curremth E Birim Profik Piti Piin inie Cotiok dune 1 6 2 Viewing results for the current run A Global summary table e Select the Results tab in Watershed Explorer e Select the Simulation Run tab in component editor Annexes A85 9 Jhiku_runoff E Simulation Runs ie Currentl Results R Simulation Run Start States Save States Name Current Description Basin Projhk amp Met Jhikhu In Basin Model Projhk iz Meteorologic Model Jhikhu In Dist ES Control Specifications June 1999 EB EA APUG Current Select the result in Watershed Explorer 4 Jhiku_runoff Simulation Runs a EA Global Summary AE break G Gage 7 lS Gage 8 rr JE JR47o ABE Outlet A 3 ed Mt R420 phy RAZOW420 hy RASOW4SO hy RAO isha he R450 sai hte R460 a hte R470 chy RAPS Components Results e Select Results Global Summary Table A86 Resource Manual on Flash Flood Risk Man
110. useful tool for the management of this risk This manual was prepared in order to provide materials for the trainees of the 1 10 August 2007 training on flash flood risk management to help them identify the various features and capabilities of two software namely HEC GeoHMS Version 1 1 and HEC HMS Version 3 1 0 for hydrological modelling of a pilot watershed Reference data from the Jhikhu Khola watershed in Nepal collected by the People and Resources Dynamics Project Natural Resources Management Programme ICIMOD was used to prepare this training manual This manual was prepared by Geographic Information System and Integrated Development Center GIS IDC Nepal under the guidance of Dr Arun B Shrestha Water Hazard and Environmental Management WHEM Programme ICIMOD Annexes A25 Overview This training manual describes the major steps to be taken in order to develop a hydrological model using HEC GeoHMS Version 1 1 and run and simulate the precipitation runoff processes using HEC HMS Version 3 1 0 The manual has two parts working with HEC GeoHMS and working with HEC HMS The HEC GeoHMS Arc View extension is used to develop the basin model and estimate the hydrological parameters for the HEC HMS precipitation runoff model The major outputs of HEC GeoHMS are basin characteristics such as the boundary of the watershed sub basin boundary contributing area slope sub basin curve number time of concentration basin lag time basin
111. zard Step 4 Classifying the combined weight map into a final hazard map The combined weight map which has many classes will be simplified by classifying the values into four classes Step 1 Assigning weight values using attribute tables The weight values that should be assigned to the individual classes are given in the tables below Seismic Weight High seismic hazard 5 Moderate seismic hazard PB Low seismic hazard a Volcanic Novoleanichazard 0 Landslide Legend Narino Region Huila o 2 O Valede Cauca o oOo ooo o 8 O Zona Cafetera O Z oOo ooo 4 O Manizales y Alrededores o 4 Valle de Aburra o ooo o A O Cundinamarca o 3 O Boyaca and Santander 2 Bucaramanga o S ooo 2 O No landslide hazard 0 O Tsunami Weight No tsunami hazard Beach Accumulation MINIO AJIAJ BR OW Po Accumulation and erosion Erosion No accumulation or erosion Coo ao A4 Resource Manual on Flash Flood Risk Management Module 2 All classes in the map Inundat will receive a weight of 5 Class No inundation hazard will receive a weight of 0 All classes in the map River will receive a weight of 4 Class No river will receive a weight of 0 All classes in the map Topograp will receive a weight of 2 and only class Altitude less than 1000m will receive a weight of 0 Here only the procedure for the first map Seismic is explained Follow the some procedure for the other maps Display

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