Watershed Delineation Extension

The ArcView Watershed Delineation extension, along with watersheds and streams data, allows for the quick and accurate delineation of watersheds for any selected outlet point.

The extension was originally developed by the Land Analysis Laboratory as part of a project for the Bureau of Watershed Conservation within the Pennsylvania Department of Environmental Protection. It is maintained and made available to anyone wishing to use it by the Penn State Extension's GIS Program

This site includes an animated demonstration of the extension that leads users through each step of the watershed delineation process. Additionally, the ArcView extension and the necessary watersheds and streams shapefiles are made available for download. Both the tutorial and downloads can be found by clicking on the drop-down menu above.

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The Watershed Delineation GIS Extension was developed by the Land Analysis Laboratory in the College of Agricultural Sciences. Special thanks go out to the e-Education Institute, housed in the College of Earth and Mineral Sciences for their development of the online demonstration modules. For more information, contact Rick Day, Director of the Cooperative Extension GIS Program, at 814-863-1615 or

The demonstration presented here uses Macromedia's Flash technology to step visitors through the use of the Watershed Delineation Extension.