|
|
| (9 intermediate revisions by the same user not shown) |
| Line 1: |
Line 1: |
| When the drainage coverage feature objects are used to create a hydrologic model the area of the polygons can be determined and used in any of the supported hydrologic models. If the points/vertices used to create the feature arcs also have z values associated with them then WMS will make a rough estimate of the longest flow path and slope along such a path. Finally, if you have derived a watershed from feature objects, but have a background DEM you can compute most of the basin data parameters using the following steps:
| | #redirect [[WMS:DEM_Basins#Compute_Basin_Data]] |
| | |
| :#[[WMS:Importing USGS DEMs|Import/Read the DEM.]]
| |
| :#[[WMS:Importing Flow Directions and Accumulations|Compute the flow directions using TOPAZ.]]
| |
| :#Use the [[WMS:Polygon Basin IDs to DEM|Polygon Basin IDs->DEM]] command found in the '''DEM''' menu in the Drainage module to assign DEM cells a basin id from the feature object polygons.
| |
| :#Choose the '''Compute Basin Data''' command from the '''Feature Objects''' menu of the Map module.
| |
| | |
| Of course, the results will only be approximate since the actual basin boundaries will not have been derived from the computed flow direction data, but it will provide a reasonable estimate. Ideally you will want to derive the basin boundaries from the DEM and flow direction data and then use the [[WMS:Computing Basin Data (DEMs)|Compute Basin Data]] command in the '''DEM''' menu of the Drainage module.
| |
| | |
| | |
| ==''Related Topics''==
| |
| | |
| [[WMS:Feature Object Guidelines|Feature Object Guidelines]]
| |
| | |
| [[WMS:Computing Basin Data (DEMs)|Computing Basin Data from DEMs]]
| |
| | |
| [[WMS:Computing Basin Data (TINs)|Computing Basin Data from TINs]]
| |
