MIKE VIEW FLOOD MAPPING Basic Tutorial

MIKE VIEW FLOOD MAPPING ADD-ON MODULE

Basic Tutorial DHI Hydroinform, 2001

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Content 1 Introduction .................................................................................................................................................... 5 1.1 Instalation ................................................................................................................................................ 5 1.2 Basic overview ........................................................................................................................................ 5 1.3 An Important note: .................................................................................................................................. 5 2 Menu structure and dialog description ........................................................................................................... 6 3 Three step procedure ...................................................................................................................................... 7 3.1 Building of the Terrain Digital elevation model (DEM) ......................................................................... 7 3.2 Results generation ................................................................................................................................... 7 3.3 Results processing and export ................................................................................................................. 8 3.4 Task 1: Generation of the flood line ........................................................................................................ 9 3.5 Task 2: Generation of the flooded area and the depth of flood ............................................................... 9 4 Building the Terrain Digital elevation model (DEM) .................................................................................. 10 4.1 Generation of terrain surface DEM from ASCII data............................................................................ 10 4.2 Generation of terrain surface DEM from DXF drawing file ................................................................. 11 4.3 Transformation of the terrain DEM....................................................................................................... 12 5 Results generation ........................................................................................................................................ 13 5.1 Setting of the area of interest boundary................................................................................................. 13 5.2 Setting of the non-flooded area ............................................................................................................. 14 5.3 Selection of the terrain DEM prepared before....................................................................................... 15 5.4 Selection of the results time step for water surface DEM generation.................................................... 15 5.5 Results type specification and results generation .................................................................................. 16 6 The display and processing of results........................................................................................................... 17 6.1 Direct display of results......................................................................................................................... 18 6.2 Results display in raster format ............................................................................................................. 18 6.2.1 Individual raster generation ............................................................................................................ 18 6.2.2 Raster list generation ...................................................................................................................... 19 6.2.3 Difference model generation .......................................................................................................... 19 6.2.4 The display of the raster or raster list ............................................................................................. 20 6.2.5 The animation of the raster list ....................................................................................................... 20 6.3 Display of contours................................................................................................................................ 21 7 Exporting of results ...................................................................................................................................... 22 7.1 Exporting of adjusted raster bitmap....................................................................................................... 22 7.2 Export of contour lines in vector format................................................................................................ 23 7.3 Export of point values ........................................................................................................................... 23 7.4 Export to ARC View compatible grid file............................................................................................. 23 8 Palettes ......................................................................................................................................................... 24 Appendix A: Description of input files ........................................................................................................... 25 Appendix B: Examples.................................................................................................................................... 26 B.1 Example1: Building of the terrain DEM from DXF file....................................................................... 26 B.2 Example2: Building of the terrain DEM from ASCII files and its transformation ............................... 28 B.3 Example 3: Flood line generation ......................................................................................................... 31 B.4 Example 4: Flood map generation ........................................................................................................ 33 B.5 Example 5: Difference between two time steps.................................................................................... 36

MIKE VIEW FLOOD MAPPING

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1 Introduction MIKE VIEW FLOOD MAPPING is add-on module of MIKE VIEW, enhancing its capabilities in presentation and post-processing of result files from MIKE 11 simulations. It is designed especially for generation and viewing of maps of flooded area, water depth maps and water level height over area of interest. It supports animation of flood maps and export of all types of results for further examination and presentation.

1.1 Instalation MIKE VIEW FLOOD MAPPING module is a special add-on module for MIKE VIEW. FLOOD MAPPING option is not available in the basic version of MIKE VIEW. Running of MIKE VIEW FLOOD MAPPING module requires MIKE VIEW application (2001 release or later) already installed on your computer and HW key with proper DHIlicence.dat file allowing the running of FLOOD MAPPING module. MIKE VIEW FLOOD MAPPING module has no special instillation set up. It can be installed from main Setup tool for MIKE ZERO platform, just selecting the FLOOD MAPPING option when installing the MIKE VIEW. In the same way can be added FLOOD MAPPING to previously installed MIKE VIEW application.

1.2 Basic overview The basic purpose of this module is computation and viewing of flooded area maps, water depth maps and water level maps in selected time steps of MIKE 11 simulation. Animation of flooded area expansion during the flood can be generated, as well as changes of water depth over area of interest. Powerful tools for results export in different file formats are also available. Generally, this module requires two types of inputs: • result file of MIKE11 hydrodynamic simulation (*.res11), containing geographic co-ordinates • digital terrain model (DEM) or terrain surface data for its building (in specific ASCII format or in AutoCad 3D DXF file format) The basic goal of flood mapping is formation of two-surfaces areal model, consisting of the terrain surface and the water surface over this terrain in selected time step of MIKE 11 simulation results. User may specify area of interest by boundary polygon. Non-flooded areas (areas, where water cannot enter – e.g. buildings or areas behind the levees) are specified by obstacle polygon or line. The water surface of the flood is generated using water levels at H-computational points from MIKE 11 result file. The water and terrain surfaces are intercrossed, resulting in actual water depth map. Depth contours are drawn; zero depth contour line represents actual flood line. The area where water depths have positive values, determines flooded area, and depth of water is interpolated to any point there. These polygons can be used repeatedly for any further results variant. An envelope line of maximum flooded area, computed through complete simulation period, (i.e. flood line) may be drawn. The user is also allowed to change colour appearance, depth intervals and other features of all types of views. A list of raster may be created for animation of the flooded area and depth changes in subsequent time steps of computational result file. This animation has all features of MIKE VIEW animation tools, and flood map animation can be synchronised with other animation windows in MIKE VIEW. Once displayed results can be exported out from MIKE VIEW in several file formats: • bitmap raster with adjusted co-ordinates (e.g. flooded area), • vector lines (e.g. flood line), • numerical point values (e.g. depth of water in given points), • ESRI ArcView compatible ASCII grid file (for further work with other GIS layers). All these features support MIKE VIEW FLOOD MAPPING as comprehensive and powerful tool for post processing of MIKE 11 simulation results, with special focus on flood mapping and flood animation.

1.3 An Important note: MIKE VIEW FLOOD MAPPING module uses some routines of the ATLAS DMT software package. Since they are based originally on the MS DOS platform, it is strongly recommended to use the names of the directories and files long maximally 8 characters and without spaces and other problematic characters. Not keeping of this rule may cause in some cases, that the model generation will not run properly.

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2 Menu structure and dialog description When opening FLOOD MAPPING pop-up menu just click the right mouse button in the Horizontal Plan window, and select the Flood Mapping item. Four-part pop-up menu appears. The first and second parts contains tools for preparation of boundary and obstacle polygons, their editing, setting, saving etc. The third part of menu allows specification of settings for the areal model generation and its computational parameters (selection of input DEM, selection of MIKE 11 results time steps and selection of results type). The last part of menu contains different export utilites. Basic menu structure:

Model building dialog and Results Presentation dialog:

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3 Three step procedu re Generally, the whole procedure of flood mapping consists of three basic steps: 1. Building of the Terrain Digital Elevation Model (DEM) 2. Results generation (i.e. intercrossing of the water levels and terrain), 3. Results processing and export. As the MIKE VIEW FLOOD MAPPING module gives to the user wide possibilities in all three steps, it is not possible to describe all the combinations of used functions. The user may find in following sections list of the possibilities given by application in particular steps with cross-reference to the detail explanation in chapter containing the Menu and Dialog description and also to the examples. Furthermore, the user may find here a brief list of steps for two typical tasks: 1. The flood line generation, 2. The flood map generation.

3.1 Building of the Terrain Digital elevation model (DEM) The Terrain Digital Elevation Model (DEM) can be created from imported data of two types: 1. Selected layers of the 3D DXF drawing file 2. ASCII text format of specific shape, described in Appendix A. The user may also use the pre-prepared terrain DEM from previous work or generated outside the MIKE VIEW FLOOD MAPPING module. Generally, the terrain DEM is independent from MIKE VIEW FLOOD MAPPING module. It should consists of two types of data: coordinates of individual points and description of the terrain edges (e.g. roads, levees, banks etc.) – this structure is maintained in ASCII data shape, where one file (PBD) contains the points coordinates and the other the edges (PSP file). The application includes a special tool for selection of the layers and type of elements, which will be used for generation, while importing the DXF drawing file. The building utilities are achievable from Build dialog, where the user should select the pathways to source files and the type of the model to be built in the combo box at the Input DEM tab page. There should be toggled OFF all of the check boxes on the Levels and Results tab pages. After files are prepared (Prepare files button), the generation could begin (Start computation button). The user should check the generated terrain model displaying it in Horizontal Plan window (dialog Results presentation/DEM). If the terrain surface was properly generated, but it is not displayed in the window, the reason may be, that results of the MIKE 11 simulation and generated terrain DEM may differ in coordinates definition. In such cases the transformation of the coordinates (flip or rotation around axes) is provided by special tool inside the MIKE VIEW FLOOD MAPPING module, achievable from Flood Mapping/Setup Model Transformation menu item. The procedure steps are in detail described in chapter 4. , useful are also examples 1 and 2.

3.2 Results generation When both types of the input (MIKE 11 result file and the terrain DEM) are ready, it is possible to intercross the water surface automatically generated from H-computation points with terrain surface built from the terrain DEM. In the Horizontal Plan window with open result file the user should specify the boundary of the area of interest (menu Flood mapping/Boundary polygon). It may spare a lot of computation time in case that only a part of area covered is in interest. The user also may specify the obstacles – never-overflooded areas inside the boundary (menu Flood mapping/Obstacles). It is useful especially when some historically recorded flood is verified and the user has some information about non-flooded areas (e.g. road, levee, railway etc.). These obstacles are used only for results display; they do not influence the computation in any way. They should not intercross, as well as they should not cross the boundary. Both types of polygons (boundary and obstacles) are saved and may be used any further. After the boundary setting the user should specify all the necessary settings for the results generation in the Build Dialog. File names and paths should be specified in the Input DEM tab page. The time steps of the MIKE 11 result file, which will be used for the results generation and the computation of the maximum envelope over the whole simulation period may be specified in the Levels tab page. Flood map is generated in any case. The type of the contours generated may be specified in the third tab page, Results type. Then the user should Prepare files and Start Computation from the same tab page. While the process is on, information windows appear at the screen, when no information window remains, the process of generation is finished. The steps of the procedure are described in the chapter 5, some useful information are in examples 3and 4.

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3.3 Results processing an d export The user may display several map themes (terrain surface, water surface and water depth), which may be combined with the vector lines of contours. Map themes may be displayed in user – defined coloured scale. Another important feature is computing and displaying of difference between two surfaces: two project variants or two time steps of computation can be directly compared. MIKE VIEW FLOOD MAPING module supports three different ways how to display once computed results: • direct viewing of surface DEM, • generation of raster (or raster list for animation and further export), • display of vector contours. Once generated surface DEM (terrain surface, water surface or water depths) can be directly displayed as raster in user-selected resolution, which is the same for any zoom. The picture is automatically re-generated directly from vector data for any zoom or new view without loss of resolution. The other way of results display is the use of raster generated from actually displayed view in the Horizontal Plan window. This raster may be saved and used any further as a raster picture; when zoomed, resolution decreases. The Raster list option allows creation of raster list containing the same type of results in selected time steps of MIKE 11 result file. This raster list may be animated, showing e.g. depth changes as flood wave progress through flood area or flooded area changes during the flood. This animation may be synchronised with animations in other windows of MIKE VIEW. Difference option allows the comparison of two surface models generating the difference raster. Difference model can be used e.g. for comparison of two variants of the project or two time steps of the same simulation result file. Raster list prepared before may be animated in Horizontal Plan window. Animation of raster list can be synchronised with animation of water dynamics in branches in the Horizontal Plan window or with any other MIKE VIEW window. This allows observation of several features of studied case simultaneously (e. g. depths of water in river branches and actually flooded area). This option greatly enhances capabilities of result presentation in MIKE VIEW. Contours of the surface (terrain of water surface) and contours of water depth may be displayed (if generated). Flood contour (a zero contour line) may be generated as an envelope from whole computation period or from selected time step of computation result. Displayed results can be exported out from the MIKE VIEW in several common file formats. Generally, following graphic elements can be exported: • point values (interpolated depth values in points given by specified co-ordinates; ASCII text output) • vector lines (*.DXF file format), • bitmap raster with adjusted co-ordinates (*.BMP and *.BMW), • export of maps in ESRI ArcView compatible ASCII grid file (*.ASC). Displayed raster may be exported as a bitmap adjusted by co-ordinates. The whole area (independently on actual view or zoom) is selected. The user may also use this bitmap as the background file in the Horizontal Plan window directly in MIKE VIEW or in many other (e.g. GIS) applications. Displayed raster map may be exported as an ESRI Arc View compatible ASCII grid file (*.ASC). To achieve exact specification of input area location, list of corner points coordinates is used for boundary rectangle placing. Generated grid file may be imported using Spatial Analyst extension into the Arc View GIS software. Displayed contours may be exported as AutoCAD drawing *.DXF file format. Point values (e. g. depth, altitude of the terrain surface or the water level surface) may be exported from displayed DEM in numerical form (ASCII file format). To achieve exact specification of location of points, where required values should be computed, input by list of coordinates of these points is used.

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3.4 Task 1: Generation of the flood line The Flood line generation is one of basic tasks when working with MIKE VIEW FLOOD MAPING module. As an example, steps necessary for flood line generation and export are listed with references to the corresponding chapters of this tutorial. More detail explanation is given in Appendix B, Example 3. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.

Open MIKE VIEW. Open result file (*.RES11) containing geographic co-ordinates in Horizontal Plan window. Generate the Terrain Digital Elevation model (DEM) [4]. It may be generated from DXF drawing file [4.2] or from ASCII data files [4.1]. Set boundary of the area of interest [5.1]. Set non-overflooded areas (obstacles) [5.2]. Leave the area boundary and obstacles visible in Horizontal Plan window. Open from pop-up menu on the right mouse button: dialog Build. Specify the name of the Info file in first input row (Load button). Select generated terrain model to the Model row [5.3]. Select time steps of result file [5.4], which you are interested in. Select Maximum envelope. Specify results type [5.5]: select only Flood contours generate. Generate selected results [5.5] by Prepare files and Start Computation buttons. Display [6.3] generated contours: Use Contours tab page of Results presentation dialog. The flood line may be exported [7] as vector [7.2] in AutoCAD DXF drawing format.

3.5 Task 2: Generation of the flooded area and the depth of flood The Flood map generation is other of basic tasks of work with MIKE VIEW FLOOD MAPING module. As an example, steps necessary for map of floodwater depth generation and export are listed with references to the corresponding chapters of this tutorial. More detail explanation is given in Appendix B, Example 4. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.

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Open MIKE VIEW. Open result file (*.RES11) containing geographic co-ordinates in Horizontal Plan window. Generate terrain digital elevation model (DEM) [4]. It may be generated from DXF drawing file [4.2] or from ASCII data files [4.1]. Set boundary of the area of interest [5.1]. Set non-overflooded areas (obstacles) [5.2]. Leave the area boundary and obstacles visible in Horizontal Plan window. Open from pop-up menu on the right mouse button: dialog Build. Specify the name of the Info file in first input row (Load button). Select generated terrain model to the Model row [5.3]. Select time steps of result file [5.4], which you are interested in. Select also Maximum envelope. Specify results type [5.5]: select Surface contours and Flood contours generation. Generate selected results [5.5] by Prepare files and Start Computation buttons. Display [6.1] generated maps: using DEM tab page of Results presentation dialog the user may directly view any of generated maps – flood depth or water surface in selected time step, or the map of maximal values over the whole flood period. Flood maps may be exported [7] from direct view as ARC View compatible grid file [7.4] (in ASC grid file format). Flood maps may be also displayed as raster [6.2.1] and then exported in adjusted raster bitmap format [7.1.].

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4 Building the Terrain Digital Elevation Model (DEM) The Terrain Digital Elevation Model (DEM) can be created from imported data of two types: 1. ASCII text format of specific shape, described in Apendix A, 2. Selected layers of the 3D DXF drawing file. The user may also use the pre-prepared terrain DEM from previous work or generated outside the MIKE VIEW FLOOD MAPPING module and skip this step of the process. The Build dialog gives access to all the necessary tools for the terrain DEM generation in both of the cases. Generation from the ASCII files is easier as the data have pre-defined structure, generation from the DXF file includes some more steps due to the import of the file.

4.1 Generation of terrain s urface DEM from ASCII data 1.

Select pop-up menu using the right mouse button in the Horizontal Plan View window containing opened result file, then select Build item. 2. Select Input DEM tab page. 3. Insert name of new control Info file 4. Insert new name of terrain DEM Model in the selected directory, where terrain model should be created. 5. Open input files (*.PBD and *. PSP). 6. Select the item from PBD, PSP in the Generate model combo box. 7. If the user wish to use the terrain contour lines for the presentation, then Generate contours toggle bars should be switched ON and inserted the height of the step of contours in meters (suggested: to be switched OFF). 8. Switch OFF the check box in the Levels tab page. No time steps are needed for terrain model generation. 9. Switch OFF the all the check boxes in the Results type tab page, no type of flood contours should be generated. 10. Clicking on the Prepare files button are some preparation processes finished and the information alert appears. Then start model generation using the Start Computation button. Using the button Save BAT the user may save the batch file with all specifications, which can be run even later, outside of MIKE VIEW FLOOD MAPPING module.

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4.2 Generation of terrain s urface DEM from DXF drawing file Selected elements from layers of 3D DXF drawing file format can be imported and Terrain Digital Elevation Model can be generated this way: 1. Select pop-up menu using the right mouse button in the Horizontal Plan View window containing opened result file, then select Build item. 2. Select Input DEM tab page. 3. Insert name of new control Info file 4. Insert new name of terrain DEM Model in the selected directory, where terrain model should be created. 5. Open input DXF file. 6. Select the item from DXF in the Generate model combo box. 7. If the user wish to use the terrain contour lines for the presentation, then Generate contours toggle bar should be switched ON and inserted the height of the step of contours in meters (suggested: to be switched OFF). 8. Switch OFF the check box in the Levels tab page. No time steps are needed for terrain model generation. 9. Switch OFF the all the check boxes in the Results type tab page, no type of flood contours should be generated. 10. Clicking on the Prepare files button are some preparation processes finished and the information alert appears. Then start model generation using the Start Computation button. Using the button Save BAT the user may save the batch file with all specifications, which can be run even later, outside of MIKE VIEW FLOOD MAPPING module. 11. While surface generation progress, several windows appear, showing actual status of generation. New dialog window then appears, allowing the user to select layers of DXF drawing, which contains required information (Selection of edge type and entities in layers). Layers and their content are displayed (and can be selected) in left part. User can select particular objects from layers using buttons in right part of window and directly assign them some type of edge. Mostly used are the P (obligatory) and L (broken, obligatory) types of lines (see figure). Obligatory edges can be used to change the smoothening of generated terrain surface between two points. For detail explanation please refer to the Help or to Example 1 in Appendix A. Layers, from which only points will be used, have X sign in Edge column. 12. In some cases, the user is asked to select the coordinate system in Co-ordinate system, extremes dialog. It is suggested to select system No. 1. 13. When all the information windows disappear, the model I generated in selected directory.

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4.3 Transformation of the terrain DEM Results of the MIKE 11 simulation and generated terrain DEM may differ in coordinates system definition. In such cases the transformation of the coordinates (rotation or flip around axes) is necessary. In case, that terrain DEM is properly generated, but not displayed in the Horizontal Plan window, the user should check the coordinates of the M11 result file and terrain DEM using the Setup Model Transformation option. 1.

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Select pop-up menu using the right mouse button in the Horizontal Plan window containing opened result file, then select Setup Model Transformation. The terrain DEM extreme coordinates are displayed in the upper rectangle. The last used transformation coefficients are displayed in the second rectangle and transformed resulting extreme coordinates are computed in the third rectangle. The lower rectangle is used for input of new transformation coefficients. The user should inset new values in the lower part of the dialog and after clicking on Compute button, newly computed values of maximal and minimal coordinate values appears. It is recommended to use only the values 1, 0 and –1 for simple transformation without distance changes. When the user finds the proper values of the coefficients (transforming the terrain DEM coordinates according to the actual coordinates of the Horizontal Plan window axes), clicking on the OK button the model is transformed. It is displayed after the redrawing of the Horizontal Plan window.

5 Results generation 5.1 Setting of the area of i nterest boundary Area of interest should be limited using closed boundary polygon. Results are generated inside the selected area only. This may spare lots of computation time in case of large areas, especially when user is interested only in partial or detail information. 1. Select the Horizontal Plan window containing opened result file (*.RES11). 2. Select pop-up menu using the right mouse button. 3. Select Flood Mapping, then Create polygon. 4. Draw a polygon in the Horizontal Plan window around the area of interest. Bitmap (or *.DXF) file containing terrain contours or previously computed flood line in the background will help you draw proper shape of boundary polygon. The larger area will be, the more computation operation will be necessary. Points of polygon are created by the left mouse button click. When the area of interest is created, close the polygon by CTRL+left mouse button. 5. For smooth interpolation it is necessary add some computational points on polygon line. Use Add points to lines option for automatic addition. 6. Set the polygon as a boundary (Set polygon as boundary). 7. Save the boundary polygon (Save boundary) 8. To load previously saved boundary polygon, use Load Boundary in the same menu; to change its visibility switch Draw ON/OFF.

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5.2 Setting of the non-floo ded area Some selected areas in the flooded area may be set as never-overflooded areas inside the area boundary – called obstacles. It is useful especially when some historically recorded flood is verified and the user has some information about non-flooded areas (e.g. roads, levees, railways etc.). These obstacles are used only for results display; they do not influence the computation in any way. They should not intercross, as well as they should not cross the boundary. 1. Select the pop-up menu by the right mouse button in the Horizontal Plan window containing opened result file (*.RES11). Then select Flood mapping, and Create polygon. 2. Draw a polygon in the horizontal plan window around the area expected to stay dry during the flood event. 3. Points of polygon are created by the left mouse button click. You may create a closed dry area (close polygon: CTRL+left mouse button) or draw only a line (end of line: SHIFT+left mouse button). This line will be not overflooded from the side of river. Using the line you may cut OFF a part of the flooded area from generation. A number of closed and open obstacles can be created. 4. Add these polygons or lines to obstacles (Obstacle/Add polygon to obstacles). 5. Save all created obstacles as *.OBS file using Obstacle/Save obstacles. 6. To load previously saved obstacles, use Load Obstacles in the same menu; to change visibility switch Draw ON/OFF .

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5.3 Selection of the terrain DEM prepared before The terrain surface model generated in previous steps (in MIKE VIEW FLOOD MAPPING module as well as from external sources) should be used for results generation. The terrain surface DEM is independent from the MIKE 11 result file. Actually opened M11 result file in the Horizontal Plan window will be used automatically. All the control information and settings are stored in Info file (*.INI) in ASCII text format. 1.

2. 3. 4.

5. 6. 7.

Select pop-up menu using the right mouse button in the Horizontal Plan window containing opened result file, then select Build item. Select Input DEM tab page in the Build dialog. Insert name of the new Info file. Results will be stored in the same directory, like the Info file. Select the terrain DEM model. The filter is used in dialog box, so displaying *.TRJ type of files (one of files created during the DEM generation). Names of *.PBD and *.PSP files will occur in following rows if they are generated. The combo box Generate model should be set to No (it concerns the terrain model only). For displaying of the terrain contour lines user should switch ON item Generate inside the Contours frame and insert height step of contours in meters

5.4 Selection of the result s time step for water surface DEM generation

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2. 3. 4.

Results of MIKE 11 hydrodynamic simulation are used as inputs for water surface DEM generation. The user may select individual time steps (Levels) and/or the envelope of maximum values reached during the whole simulation period. Water levels are then computed only for here selected time steps included in MIKE 11 result file (*.RES11). Select pop-up menu using the right mouse button in the Horizontal Plan window containing opened result file, then select Build dialog and Levels tab page. Switch ON time steps of computation results to be used for results. Switch ON Save maximum envelope, to generate the envelope flood contour too. Select type of points at cross sections, which will be used for surface building. Depth of water, originally assigned in any computation point to the centre of cross section, will be distributed to these points of the same cross section. The default values (Marks 1, 3 of the cross section) are recommended.

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5.5 Results type specifica tion and results generation

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4.

5. 6.

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Flood contours, contours of water surfaces and depth contours can be generated for previously selected time steps. Contours are generated in separate files. Their names are composed from two parts: prefix (common for type of contour line), containing 1-4 characters, and the rest of the name, being the numerical order among the selected time levels. When all the results are specified, you may generate them or close the Build dialog (settings are stored) or save all the settings in the batch file for further use. Select Results type tab page in the Build dialog. Switch ON these types of contours, which should be generated. Insert vertical distance step of contours (in meters). If only flood maps are to be generated (without any contours), just left all these check boxes OFF. To save all the settings of the run, click on the button Save BAT and save the batch file with all specifications to the batch file. It can be run later, even outside of MIKE VIEW FLOOD MAPPING module. Prior the computation some files has to be prepared. Click on button Prepare files and wait while the information alert appears. Start computation of the flood maps and flood lines using the Start computation button. The user can see several different information windows, as particular processes proceed during the generation procedure. When no information window remains, the process of results generation has finished.

6 The display and pr ocessing of results Results may be processed and displayed after computation. The user may display several map themes: terrain surface, water surface and water depth, which can be combined with the vector lines of contours. Map themes may be displayed in user – defined coloured scale. Another important feature is computing and displaying of difference between two surfaces: two project variants or two time steps of computation may be directly compared. MIKE VIEW FLOOD MAPING module supports three different ways how to display once computed results: • direct viewing of surface DEM via raster, • generation of raster (or raster list for animation and further export), • display of vector contours. All tools for the results processing and displaying can be reached from maim menu on right mouse button. Selecting the Results item will rise the Results Presentation dialog. 1.

2. 3.

Select pop-up menu using the right mouse button in the Horizontal Plan window containing opened result file, then select Results item. Model to be displayed is selected using the info (*.INI) file. The type of result and time step is displayed in left lower corner of Horizontal Plan window, when raster type of results is displayed. Alternatively, the same information is displayed in right lower corner of Horizontal Plan window for line result type. When moving by mouse cursor over the Horizontal Plan window, the actual position coordinates are displayed in bottom line of the Horizontal Plan window.

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6.1 Direct display of resul ts Once generated surface DEM (terrain surface, water surface or water depths) can be directly displayed as raster in user-selected resolution, which is the same for any zoom. This means, that any detail can be seen without loss of resolution. The picture is automatically re-generated directly from vector data for any zoom or new view. It may take some time in case when picture is large. This type of display is suitable for brief control of generated results (using low resolution) or for zooming to details (with high resolution). 1. Select the DEM tab page in the Result presentation dialog. 2. Open Info file of previously generated model (Load button). 3. Insert Resolution for display. 4. Select type of DEM model to be displayed in Model combo box. Terrain surface, Water surface or water Depth are available. 5. Select time level from list of generated result levels (effective only in case of water surface and depth). 6. Toggle ON Draw check box and click on OK. 7. Select proper scale and colours in the colour palette (chapter 8).

6.2 Results display in ras ter format The other way of results display is the use of raster generated from actually displayed view in the Horizontal Plan window. This raster may be saved and used any further as a raster picture; when zoomed, resolution decreases. The Raster list option allows creation of raster list containing the same type of results in selected time steps of MIKE 11 result file. This raster list may be animated, showing e.g. depth changes as flood wave progress through flood area or flooded area changes during the flood. This animation may be synchronised with animations in other windows of MIKE VIEW. Difference option allows the comparison of two surface models generating the difference raster.

6.2.1 Individual raster genera tion The user may simply generate an individual raster from actually displayed results and save it. 1. Display selected type of results using direct display (see chapter 6.1). Select Raster tab page. 2. Select Info file of generated model. 3. To see the raster immediately after its generation, switch ON Draw raster. 4. In frame Generate raster select Individual. 5. To add some short text information to the picture insert it in Text prefix row (optional). 6. Insert File name prefix: first part of the raster file name (max 4 characters). The second part is raster order number increasing from 0. 7. Input Resolution of raster. There are two ways: insert number of pixels, used for display in both directions (Cell option), or insert directly length of both pixel sides in meters (Meter option). 8. Click on Generate raster to generate raster in memory. When ready, an alert appears. 9. Raster can be saved as *.RDM file any time using Save raster option. This internal format saves all the information of given type of result map as numerical values in given grid. 10. Click on OK to display the raster. 11. How to export raster as a bitmap see chapt. 7.2.

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6.2.2 Raster list generation Moreover the individual raster, also raster list may be generated from Info file containing more than one time step of computed results. The procedure is similar to individual raster generation. 1. Select Info file of generated results in first row of Raster tab page. 2. In frame Generate raster select Raster list and type of model: Water surface or Depth. 3. Optionally, some short text information to the picture in Text prefix row can be added. 4. Insert File name prefix: the first part of raster file name. The second part is raster order number increasing from 0. 5. Input Resolution of raster. There are two ways: insert number of pixels, used for display in both directions (Cell option), or insert directly length of both pixel sides in meters (Meter option). 6. Click on Generate raster to generate raster in memory. When ready, an alert appears. 7. Save generated raster list as *.RDL file for further use. Raster are saved in *.RDM files. 8. Click on OK and the first raster of the list is displayed. 9. To show rest of raster list use Animation procedure.

6.2.3 Difference model gener ation Difference model can be used e.g. for comparison of two variants of the project or two time steps of the same simulation result file. In principle, vertical difference between two independent surfaces is computed. These surface DEM are represented by actually selected Info (*.INI) file and by any other, set as Difference info file (*.INI), generated in separate directory. If both of these info files contain the same number of time levels, they are subtracted according to the increasing numerical order. If the first Info file contains only one time level, all time levels of Difference info file will be subtracted from this one time level. 1. Select Raster tab page in the Results presentation dialog. 2. Select Info file of the first model. 3. Select raster list in the frame Generate raster and type of model: Differences. 4. Load the second model for making differences (Difference info file). 5. Some short text information to the picture may be added optionally to the Text prefix row. 6. Insert File name prefix: the first part of raster file name. The second part is raster order number increasing from 0. 7. Input resolution of raster in both directions. 8. Click on Generate raster to generate raster in memory. When ready, information alert appears. 9. Save generated raster list as *.RDL file for further use. Raster itself is saved as *. RDM file. 10. Clicking on OK the first raster of the list is displayed. If the palette has no valid colour scale, set manually Equidistant intervals in palette menu (on the right-mouse button). 11. To show rest of raster list use Animation. 12. To export actual raster as a bitmap see sec. 7.2).

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6.2.4 The display of the raste r or raster list The user can display the raster or raster list generated and saved before. 1. Select Raster tab page of Results Presentation dialog. 2. Click on Load Raster(s) button. 3. Select raster (*.RDM) or raster list (*.RDL) filter. RDM and RDL are internal formats suited for fast raster display. 4. Select proper file. 5. Switch ON Draw raster. 6. Click on OK. 7. The selected raster or the first raster from the list is displayed. 8. To display rest of the raster list, use Animation (see next section).

6.2.5 The animation of the ra ster list Raster list prepared before can be animated in Horizontal Plan window. Animation of raster list can be synchronised with animation of water dynamics in branches in the Horizontal Plan window or with any other MIKE VIEW window. This allows observation of several features of studied case simultaneously (e g. depths of water in river branches and actually flooded area). This option greatly enhances capabilities of result presentation in MIKE VIEW. 1. 2.

3. 4. 5. 6. 7.

8.

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Display raster list generated before. Select Options in the Horizontal Plan window (right mouse button / Options) and then Plan Type. Select Draw branches as Water Level or Discharge Grid points. Select Plot Type: Animation. Select Synchronised in the pop-up menu opened by the right mouse button (optional). Select Run button from Animation toolbar, or select menu Animation / Run. When animation proceeds to the time step associated with generated raster, this new raster is displayed. Control of animation is the same as standard MIKE VIEW using.

6.3 Display of contours Contours of the surface (terrain of water surface) and contours of water depth may be displayed (if generated). Flood contour (a zero contour line) may be generated as an envelope from whole computation period or from selected time step of computation result. 1. Select Contours tab page of the Results presentation dialog. 2. Select Info file of generated model. 3. Select type of DEM model to be contoured (Terrain surface, Water surface or Depth of water) or select only the Flood line display. 4. Select time step from the list or select Maximum for the envelope (display flood line). 5. Switch ON Draw. 6. Colour palette can be used to colorize lines by height (depth). 7. To change thickness of the line use Line size option. 8. Select OK button. 9. Contours may be also drawn over raster, displayed previously. 10. Export of contours in DXF vector file format is described in chapter 7.2. ).

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7 Exporting of result s Displayed results can be exported out from the MIKE VIEW in several common file formats: • point values (interpolated values of depth in point of specified co-ordinates; ASCII text output), • vector lines (*.DXF drawing file format), • bitmap raster with adjusted co-ordinates (*.BMP and *.BMW), • export of maps in ESRI ArcView compatible ASCII grid file (*.ASC). All of export utilities may be reached from pop-up menu using the right mouse button in the Horizontal Plan window containing opened result file and displayed surface model. Four items in bottom part of menu may be used for export: Export as bitmap, Export contours, Export point value from DEM and Export to ArcView.

7.1 Exporting of adjusted raster bitmap Displayed raster may be exported as a bitmap adjusted by co-ordinates. The whole area (independently on actual view or zoom) is used. The user may also insert this bitmap as the background file in the Horizontal Plan window directly in MIKE VIEW or in many other (e.g. GIS) applications. 1.

2. 3. 4.

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Display raster with results. (For selection of raster from raster list run animation and pause it when desired raster is displayed). There is important difference: When using the Cell option (insert to the lines the total number of the pixels in both directions inside the window), then the picture, when used without coordinates stored in the BMW file, will be deformed, according the actual window sides ratio. To prevent his deformation, option meter should be used and number of meters represented by one pixel should be inserted. If the exported bitmap will be used only with coordinate adjustment, both options are useful, depending on shape of the area. Select Export as BMP in the pop-up menu. Select directory and insert the name of the bitmap file to be created. Two files then appears: *.BMP containing bitmap of raster map (without gridlines, boundary lines etc.) from whole area and *.BMW containing co-ordinates information for the geographical adjustment of bitmap picture.

7.2 Export of contour line s in vector format Displayed contours may be exported as AutoCAD drawing *.DXF file format. The file with DXF format may be also used as the background file in the MIKE VIEW Horizontal Plan window. 1. Display contour (chapter. 5.4) from results. 2. Select Export contours in the pop-up menu. 3. Select directory and name of the DXF file.

7.3 Export of point values Point values (e. g. depth, altitude of the terrain surface or the water level surface) can be exported from displayed DEM in numerical form (ASCII file format). MIKE VIEW FLOOD MAPPING routines allow interpolation of these values in any point inside the boundary. To achieve exact specification of location of points, where required values should be computed, input by list of coordinates of these points is used. Resulting output file is ASCII text file containing four columns: name of point, X and Y co-ordinates and computed depth or altitude of the point. 1. Display DEM (e.g. by direct display, chapter 5.2) from results, which you want to export. Select Export Point Value from DEM option from Flood Mapping pop-up menu. 2. Small window containing first row of the table appears. The user may input the rows the Name, X and Y coordinates of points, where values of actual surface DEM should be exported (computed Z coordinate). Using the Load button may be opened previously saved list of points in TXT file format. Using buttons in right upper corner may be added or deleted row of table. 3. When points are defined, click on the Export button and save generated TXT file to selected directory. The format of this file is simple ASCII text in three columns separated by space characters, containing name, X and Y coordinates and exported values from actually displayed DEM. The first row contains the name of type DEM, from which values were exported (see the example).

7.4 Export to ARC View co mpatible grid file Displayed raster map may be exported as an ESRI Arc View compatible ASCII grid file (*.ASC). To achieve exact specification of input area location, list of edge points coordinates is used for boundary rectangle placing. Generated grid file may be imported using Spatial Analyst extension into the Arc View GIS software. 1.

2.

3. 4.

Display DEM (e.g. by direct display, chapter 5.2) from results, which you want to export. Select Export to ArcView option from Flood Mapping pop-up menu. Define extreme co-ordinates of selected rectangle to be imported (co-ordinates of actual cursor location are displayed in bottom info line of Horizontal Plan window). Define the grid cell size (in meters). Select directory and name of file for grid file export. Click on OK. The previously saved file may be used for coordinate definition (Load coordinates button).

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8 Palettes The user can handle colours, range and some other features of map display using the palette options. Up to three different colour palettes may be opened at the same time. Default palette (Palette) opens with Horizontal Plan window. Palette Model appears when you browse Results (DEM or Raster). Palette Contours appears with Contour display. Clicking by right mouse button to the palette window you obtain the pop-up menu where some options are editable.

The user can Save and Load palette settings in *.PAL file format. Equidistant Intervals option allows change of intervals and limits of colour scale. Option Edit intervals allows to change individual values assigned to colour intervals. After it is manually changed user should Check Intervals assigned to colours. The actual setting reset allows option Reset Interval. Palette appearance can be changed by Palette type option and the actual appearance set as default (Set as default). You can also change the font used in legend. Last option (Apply) can be used when need to redraw the display after changes. In most cases it is redrawn automatically.

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Appendix A: Description of input files formats MIKE VIEW FLOOD MAPPING module requires two file types on input: 1. Result file of MIKE 11 hydrodynamic simulation (*.RES11), which contains geographic co-ordinates. 2.The digital elevation model of terrain. User can input terrain model in three ways: b) ASCII files of terrain surface points and list of edge lines between these points should be prepared in pre-scribed format (*.PBD and *.PSP ASCII files, see example below). The terrain DEM is then generated directly using MIKE VIEW FLOOD MAPPING module. c) Open pre-prepared DEM, generated during previous work in MIKE VIEW FLOOD MAPPING module. d) Open pre-prepared DEM generated by DEM Atlas software outside the MIKE VIEW FLOOD MAPPING module.

Example of File formats: 1. File type *.PBD (points for DEM building) structure: name X- coordinate Y- coordinate (values are separated by spaces)

altitude

example: H73 2500.000000 40500.000000 58.259125 H75 3859.480957 38960.222656 54.641888 H77 5784.233398 38080.437500 51.093067 H79 7357.528320 36663.707031 47.625469

2. File type *.PSP (egdes in DEM) structure: type of edge name of point name of point name of point . . . (every value is on new row) example: .l 1 H73 H75 H77 .l 1 BOD18553 BOD18554 .r 1 BOD12530 BOD12531 BOD12532 .r 1 BOD12530 BOD12529

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Appendix B: Examples B.1 Example 1: Building of the terrain DEM from DXF file If the 3D DXF drawing file containing points and edges of the terrain surface is available, the terrain model can be generated from selected layers of this file. Steps of the procedure closely follow the chapters 4.2 of the Tutorial. The detailed explanation of types of the surface edges is included. All the files used are part of the installation package and may be found in the EXAMPLES/EXAMPLE1 directory.

1.

The generation of the terrain model is possible from menu accessible in the Horizontal Plan window. So, it is necessary to open any M11 result file, even without any connection to the terrain model. Try to open some of the result files included in EXAMLES 2 or 3, for example EXAMPLES/EXAMPLE2/DATA/ WAVE.RES11 result file. It is automatically displayed in the Horizontal Plan window. 2. Insert new name of the Info file (EXAMPLE1/TERRAIN/TERRAIN1.INI) and name of the terrain model to be built (EXAMPLE1/TERRAIN/TERRAIN1) in the Build/Input DEM tab page. 3. Open DXF file containing the terrain data (EXAMPLE1/DATA/TER1.DXF) 4. Select type of generation: from DXF and switch OFF Contours generation 5. Switch OFF Save maximum envelope Check box in the Levels tab page. 6. Switch OFF all the check boxes of contour generation in the Results Type tab page. 7. Prepare files. When ready, information alert is launched. 8. Start Computation. Information windows appear during the generation. 9. In next dialog window the user should select layers of DXF drawing, which will be used. In this case, DXF file was viewed before the import to the MIKE VIEW to recognise content of the particular layers. According to picture, following selection was done: points only were taken from layer 30 (symbol x in column Edge). Regarding the type of edge used in the drawing L- type of edges were assigned to lines and polylines in layers 1, 6 and 7; P- type of edges to lines and polylines in layers 4, 5 and 8. No elements were taken from Construction layer and Pattern_class layer. 10. When clickin on Start button, the rest of the generation process will run.

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Some detailed explanation concerning the dialog elements and surface edges meaning is necessary here: Number in columns of the table means number of elements, which will be used for DEM generation (symbol x indicate, that no element will be used). Elements can be selected using buttons on right side of dialog window, if some layer (or layers) is active. Several obligatory edge types (as indicated in Edge column) can be assigned to elements (namely to lines and polylines) in layers using Selection of edge type button. Obligatory edges are used to influence triangular shape of generated surface and its smoothness. Connections between points during triangular network establishing will respect position of the edge. Moreover, special features of obligatory edges can influence smoothness of generated surface. Most commonly used types of edges are listed bellow: P… Obligatory edge. This type does not influence smoothness of generated surface in any direction, but only triangular network shape. It can be used in case of ridge-lines or valley lines, eventually to make visible borders or other lines on the terrain surface. L… Broken obligatory edge. Moreover the P – edge features, this type influences smoothness of surface in transversal direction (where surface will be not smooth, but broken). In altitudinal direction surface will be smoothed. This type of edge is used namely for design of terrain breaks (slope edges, banks, ravines, roads, border-stones, ditches etc.). R… Direct edge. It is really direct spatial connection between two points. No smoothing is allowed in both directions. This type of edge is used in case of sharp breaks at surface, e.g. in case of artificial formations modelling (concrete constructions, buildings, bridges, walls…).

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B.2 Example 2: Building of the terrain DEM from ASCII files and its transformation If the input ASCII files in format pre-scribed in the Appendix A (e.g. exported from the ATLAS DMT software) are available, the terrain model can be generated from them. The transformation of the once generated terrain DEM (from any kind of source) is also demonstrated in this example. Steps of the procedure follow the chapters 4.1. and 4.3. of the Tutorial. All the files used are part of the installation package and may be found in the EXAMPLES/EXAMPLE2 directory. 1.

2.

3. 4. 5.

6. 7. 8.

9.

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Open EXAMPLES/EXAMPLE2/DATA/ WAVE.RES11 result file. It is automatically displayed in the Horizontal Plan window. Insert new Info file name (EXAMPLE2/TERRAIN/TERRAIN.INI) and name of the terrain model to be built (EXAMPLE2/TERRAIN/TERRAIN) in the Build / Input DEM tab page. Open files containing source ASCII data (EXAMPLE2/DATA/TER2.PBD and .PSP) Select type of generation: from PBD, PSP and switch OFF Contours generation Switch OFF Save maximum envelope Check box in the Levels tab page.

Switch OFF all the check boxes of contour generation in the Results Type tab page. Prepare files. When ready, information alert is launched. Start Computation. Information windows appear during the generation. When no window appears for some time, the generation finished. Display generated terrain surface using the DEM tab page in the Results presentation dialog. Open the proper file (EXAMPLE2/TERRAIN/TERRAIN.INI), select Terrain type of model and switch ON Draw check box (see next figure). Press OK button.

10. Although the model was properly generated, it is not displayed in the Horizontal Plan window range. 11. Use the Setup Model transformation menu item. DEM transformation for the presentation dialog will open. 12. It is evident, that the terrain DEM coordinates (in upper rectangle of the window) are just negative in relation to the actual Horizontal Plan window axes. It is necessary to make change signs of all the terrain model coordinate values. The transformation coefficients –1, 0, -1, 0 are proposed. New coordinates of terrain DEM can be pre-computed for these values (see the picture) using the Compute button. These values are correct (in the third rectangle) and whole terrain DEM can be transformed using the OK button. 13. Redraw the Horizontal Plan window to see changes. 14. A note: terrain palette used in picture below is saved as the PAL file in the directory: EXAMPLE2/TERRAIN/TERRAIN.PAL.

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B.3 Example 3: Flood line generation One of most basic task of FLOOD MAPPING is displaying of the Flood line. The terrain DEM, generated in Example 2 is used as input together with MIKE11 result file of real flood event. Steps of the procedure follow chapters 5.1, 5.3, 5.4. and 5.5. of the Tutorial. All the files used are part of the installation package and may be found in the EXAMPLES/EXAMPLE3 directory.

1.

2.

3.

4. 5.

6. 7.

Open EXAMPLES/EXAMPLE3/DATA/ WAVE.RES11 result file. It is automatically displayed in the Horizontal Plan window. For further work may be useful to put to the window background the map image, stored in the directory (EXAMPLE3/ DATA /MAP.BMP) – map coordinates for adjustment are available in MAP.BMW file. Set the area of the interest boundary. The user may use prepared boundary polygon – using Boundary polygon/Load boundary option open the file (EXAMPLE3/ DATA /BOUNDARY.POL). Alternatively the user may to create new boundary polygon by the procedure described in chapter 5.1 of the tutorial and save it. Set the never-overflooded obstacles. The user may use prepared obstacles: using Obstacle/Load obstacles option open the file (EXAMPLE3/ DATA /OBSTACLES.OBS). Alternatively the user may to create new obstacle lines and polygons by the procedure described in chapter 5.2 and of the tutorial save it.

Left the boundary visible within the Horizontal Plan window. Open Build dialog, Input DEM tab page. Insert new name of the Info file (EXAMPLE3/RESULTS/FLINE.INI) and select the name of the terrain model (EXAMPLE3/TERRAIN/TERRAIN.TRJ). Select no type of generation: No and switch OFF Contours generation. Switch ON Save maximum envelope Check box in the Levels tab page.

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8.

In the Build/Results type switch ON the first check box for Flood contours generation. 9. Prepare files. When ready, information alert is launched automatically. 10. Start Computation. Information windows appear during the generation. When no window appears for some time, the generation finished. 11. The user may check computed results by displaying them using the Contours tab page in the Results Presentation dialog. Open the proper file (EXAMPLE3/ RESULTS/FLINE.INI), select Flood line type of model and switch ON Draw check box (see next figure). Press OK button. The line, where the generated water surface crosses the terrain surface is displayed (green line, see the picture below).

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B.4 Example 4: Flood map generation The other of most basic tasks of FLOOD MAPPING is displaying of the Flood Map. MIKE VIEW FLOOD MAPPING module allows generating the map of the flood depths, map of the water surface and flood contours during one run which may be even combined with flood contour generation. This example demonstrates generation of the map of flood depths and water surface for maximum envelope over the flood and for one selected time step of the MIKE11 hydrodynamic simulation results. The terrain DEM, generated in Example 2 is used as input together with MIKE11 result file of real flood event. Steps of the procedure follow chapters from 5.1 to 5.5 of the Tutorial. All the files used are part of the installation package and may be found in the EXAMPLES/EXAMPLE4 directory. 1.

2.

3.

Open EXAMPLES/EXAMPLE4/DATA/ WAVE.RES11 result file. It is automatically displayed in the Horizontal Plan window. For further work may be useful to put to the window background the map image, stored in the directory (EXAMPLE4/ DATA /MAP.BMP) – map coordinates for adjustment are available in MAP.BMW file. Set the area of the interest boundary. The user may use prepared boundary polygon – using Boundary polygon/Load boundary option open the file (EXAMPLE4/ DATA /BOUNDARY.POL). Alternatively the user may to create new boundary polygon by the procedure described in chapter 5.1 of the tutorial and save it. Set the never-overflooded obstacles. The user may use prepared obstacles– using Obstacle/Load obstacles option open the file (EXAMPLE4/ DATA /OBSTACLES.OBS). Alternatively the user may to create new obstacle lines and polygons by the procedure described in chapter 5.2 and of the tutorial save it. In this particular example it was known, that the road No. 305 with bridge and railway in the northern part, highway No11 in eastern part of the area and the farm in the south were not over flooded during this flood event. To schematise this situation, closed polygons (railway, road 305 and farm area) and one line (highway) were created, added to obstacles and saved (see the picture: dark blue line = boundary, red line = obstacles).

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4. 5.

6.

7.

8.

Left the boundary and (eventually) obstacles visible within the Horizontal Plan window. Open Build dialog, Input DEM tab page. Insert new name of the Info file (EXAMPLE4/RESULTS/FLMAP.INI) and select the name of the terrain model (EXAMPLE4/TERRAIN/TERRAIN.TRJ). Select type of generation: No and switch OFF Contours generation.

Switch ON Save maximum envelope Check box in the Levels tab page. Select time steps of the simulation to be used.

In the Build/Results type switch ON check boxes for Surface contours and Depth contours generation 9. Prepare files. When ready, information alert is launched automatically. 10. Start Computation. Information windows appear during the generation. When no window appears for some time, the generation finished. 11. The user may check computed results by displaying them using the DEM tab page in the Results Presentation dialog. Open the proper file (EXAMPLE3/RESULTS/ FMAP.INI), select Depth or Surface type of the model and switch ON Draw check box (see next figure). Press OK button.

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MIKE VIEW FLOOD MAPPING

35

B.5 Example 5: Difference between two time steps One of more special features of MIKE VIEW FLOOD MAPPING module is the possibility to generate the difference between two user-defined surfaces. This feature allows simple comparison of e.g. differences between two variants of hydrodynamic simulation results or two time steps of identical simulation. This example describes the creation of the map of depth differences between two time steps on the beginning of the flood wave; the time interval between is 6 hours. Thus, the difference map may be interpreted as the increase of water level in flood area after 6 hours of flooding. The terrain DEM, generated in Example 2 is used as input together with MIKE11 result file of real flood event. Flood maps were generated using the procedure described in detail in EXAMPLE 4 . Steps of the procedure follow chapters from 5.1 to 5.5 of the Tutorial and also Example 4 (flood map generation), so these steps are not described in details. The difference file generation is described in chapter 6.2.3 of the Tutorial. All the files used are part of the installation package and may be found in the EXAMPLES/EXAMPLE5 directory. 1.

2.

3.

4.

5.

6.

7.

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The first steps lead to generation of two surface DEM: one for time level 1.1.1999 12:00 and the other for 1.1.1999 18:00. The procedure for flood maps generation is the same as in EXAMPLE 4, so we refer for detail to this example. These models are generated in directories EXAMPLE5/FIRST (1.1.1999 18:00) and EXAMPLE5/ SECOND (1.1.1999 12:00). Open EXAMPLES/EXAMPLE5/DATA/ WAVE.RES11 result file in the Horizontal Plan window. Open Results Presentation dialog, Raster tab page. Load to the first Info file the model (EXAMPLE5/FIRST/FIRST.INI). Select Raster list/Differences model in the Generate raster frame and Load to the Difference info file generated model (EXAMPLE5/SECOND/SECOND.INI) and add some text to Text prefix edit row optionally. Insert required resolution of the raster and click on Generate raster button. When ready, an information alert appears. To save the raster in internal RDM file format, use the Save raster(s) button (EXAMPLE5/DIFFER/DIFFER.RDL). Click on OK button. Open again Results Presentation dialog, Raster tab page. Using Load Raster (s) button open the saved raster list DIFFER.RDL. Toggle ON Draw raster check box. The map of depth differences is displayed in given resolution. In case that colour scale is not propriate, set manually Equidistant intervals in palette menu (on the rightmouse button). The palette for depth differences is saved in the DIFFER directory; the palette for computed water depths (FIRST and SECOND) is saved in DATA directory (both with PAL extension). For exporting procedure refer to the Tutorial, chapter 7.