topic Sewer Inlet Catchment Delineatoin in ArcGIS Spatial Analyst Questions

Sewer Inlet Catchment Delineatoin

BrianJeffries — Fri, 22 Nov 2013 20:42:50 GMT

Hello, I am trying to use arcmap and the hydrology or hydro tools to delineate the catchment for a single sewer inlet location. I have 3 ft by 3 ft DEM data and a single vector point dataset. I'm currently using the Fill and Flor Direction Tools and then the Watershed tool to get the catchment area. However, I am not getting good results and I am not sure these tools were designed to be used on such a small scale.

I have attached a picture of one of my test runs. I'm not sure why the delineated watershed stops where it does instead of continuing to go up, since the flow direction value of 4 should be flowing down. (relative to the picture.)

If anyone has done something similar to this or has any suggestions It would be greatly appreciated. Thanks.

[ATTACH=CONFIG]29295[/ATTACH]

Re: Sewer Inlet Catchment Delineatoin

curtvprice — Fri, 22 Nov 2013 20:53:31 GMT

To get appropriate results, you probably need to specify the raster environment -- especially if you are providing vector data (points) that are going to be rasterized on the fly when you run the Watershed tool.

The relevant environments include:

Extent (must include the area you want to delineate)
Snap Raster
Cell Size

Hope this helps.

Re: Sewer Inlet Catchment Delineatoin

BrianJeffries — Sat, 23 Nov 2013 22:28:00 GMT

To get appropriate results, you probably need to specify the raster environment -- especially if you are providing vector data (points) that are going to be rasterized on the fly when you run the Watershed tool.

The relevant environments include:

Extent (must include the area you want to delineate)
Snap Raster
Cell Size

Hope this helps.

Thanks for the quick reply. This did the trick. Thanks for the help!