Geospatial Hydrologic Modeling Extension HEC-GeoHMS, User’s Manual. Public Domain That information is also provided in Appendix E of this manual for. This tutorial is designed to expose you to basic functions in HEC-GeoHMS ( ArcGIS version) to create input files for hydrologic modeling with HEC-HMS. Step 7: Terrain processing and HEC-GeoHMS model development The DEM, land use and soil data used in this tutorial are already clipped.
|Published (Last):||25 March 2016|
|PDF File Size:||14.65 Mb|
|ePub File Size:||3.24 Mb|
|Price:||Free* [*Free Regsitration Required]|
For this tutorial we will run the model in steady state condition.
Even if we did not create a gage file, there will be a gage file created when the met model file is created. After the computations are complete, the BasinSlope field in the input Subbasin feature class is populated.
This part of gwohms exercise will expose you to some of the Watershed Processing functionality in Arc Hydro. We are done with geometric data! For showing the river profile we use the River Profile Tool.
If you expand the CedarCreek basin in watershed explorer, you will see the list of junctions, reaches and subbasins. You will get a menu of parameters that you can assign. Fill-in the name and comment as shown below in the form below. Comparing this catchment area with the contours, I think there is tutoriaal mistake.
Creating River Banks Bank lines are used to distinguish the main channel from the overbank floodplain areas. Upon successful completion of the process, the flow direction grid Fdr is added to the map. Open the attribute table of Catchment.
The River Auto Name function assigns hutorial to river segments.
HEC-GeoRAS Export Error | GeoNet
The minimize area change will reduce the impact of change in cross-sectional area as a result of points removal. Meteorologic Model We do not have any meteorologic data temperaturerainfall etc at this point. For this exercise geohks will geohmd the easy route, but you may want to populate these features for other studies depending on your tutorisl needs. Try a continuous symbology instead of a banded symbology and take a closer look at the area that you suspect is “wrong”.
For this exercise, choose 25 km 2 as the threshold area, and click OK. Zoom-in to the area marked in the rectangle below:. Jakub Sisak GeoGraphics Confirm cross-sections data, make sure all Import Data boxes are checked for crosssections, and click OK accept default values for matching tolerance, round places, etc. The output is the Stream Grid named Str, default tutkrial that can be overwritten Objective methods for the selection of the stream delineation threshold to derive the highest resolution network consistent with geomorphological river network properties have been developed and implemented in the TauDEM software http: Save edits, and stop editing.
Step by Step: Flood Hazard Mapping | UN-SPIDER Knowledge Portal
If you have an existing shapefile or feature class with a set of points that you would like to use instead of interactively creating points, you can do so by using the following guidelines:.
Confirm the inputs, and click OK. Creating a river centerline Let us first start with river centerline. After finishing digitizing the upper Baxter Reach, save the edits.
You can write some metadata if you wish,and finally choose the outside MainView Geodatabase for Project Data Location, and browse to your working directory where cedar. The Longest Flow Path tool will create a feature class with polyline features that will store the longest flow path for each sub-basin. WatershedPoint and Watershed are default names that can be overwritten.
After this process is finished, open the attribute table of XSCutLines3D feature class and see that the shape of this feature class is now PolylineZ. This function converts a catchment grid into a catchment polygon feature. Another main task tutoril we want to do is to edit data related to structures. Before we move forward let us make sure that the reaches we just created are connected, and populate the remaining attributes of the River feature class.
Step by Step: Flood Hazard Mapping
When you come close to the junction, zoom-in, geohks you will notice that the tool will automatically try to snap or hug! All other cells in the Stream Grid contain no data. Confirm the input Subbasin and River files, and click OK. Upon successful completion of the process, the link grid StrLnk is added to the map.
The next step is to prepare a look-up table that will have curve numbers for different combinations of land uses and soil groups. This default name can be overwritten. This part could be challenging sometimes. In addition, HEC-GeoRAS requires the land use polygons to be non multi-part features a multipart feature has multiple geometries in the same feature. Entering Flow data and boundary conditions. Confirm the input datasets to be checked, and click Geojms. In this context a watershed, such as was delineated above is the entire area upstream of a point, while a subwatershed is the area that drains directly to a point of interest excluding any area that is part of another subwatershed.
If cells with higher elevation surround a cell, the water is trapped in that cell and cannot flow. We are almost done with GeoRAS pre-processing. You can also look at the log file and make sure there are no errors in the data by scrolling to the bottom of the log file as shown below:.
Add cngrid curve number grid from Layers folder to the map document.