This application is designed to for internal use to delineate drainage areas. The application is maintained by LDS GIS.
Navigate to the location of your study area. The Flow Accumulation layer (blue lines) on that map are your visual guide on where you want to place your pour point when using the drainage area tool. You can click on the Flow Accumulation Grid and determine the drainage area in acres. Please be very mindful to limit the geoprocessing extent of the tool. The geoprocessing extent is the geographic area of interest to be applied to the tool. The larger the geoprocessing extent the longer the tool will take to run and the more resources the tool will consume. The Watershed layer, Watershed Management Areas layer, Sub Watersheds layer and the Flow Accumulation Layer can all be used to estimate the size of your drainage area. Please zoom in as close as you can to the estimated extent of your drainage area.
| Parameter | Explanation |
|---|---|
| Pour_Point_Output | The Pour Point is where the user inputted Pour Point snaps to the Flow Accumulation layer. The Pour Point will snap to the lowest elevation point within 5 meters of where the user drops the point on the map. This is a output parameter for the tool. |
| Drainage_Area_Final | The Drainage Area is the boundary of the drainage areas. You can click on the polygon and see the drainage areas in acres. |
| PourPoint_Input | User provided point to delineate upstream. |
| Process_Extent | User provided area for processing extent. |
| esri_out_feature_service_name (Optional) | The name of the optional feature service to create on the federated server containing the result of this tool. If no name is specified an output feature service will not be created. |
There are no code samples for this tool.
FFX, LDS, Land Development Services, SDID, Drainage Area Delineation Tool, Watershed
Fairfax County, Land Development Services
The geographic data layers produced by the Government of Fairfax County, Virginia (“Fairfax County”), and any associated maps and applications, are provided as a public resource. While every reasonable effort is made to ensure the accuracy and completeness of the data, Fairfax County makes no warranties, expressed or implied, concerning the accuracy, completeness or suitability of its data, and it should not be construed or used as a legal description. Please see https://www.fairfaxcounty.gov/maps/disclaimer for further details.