Skip to main content
ARS Home » Pacific West Area » Tucson, Arizona » SWRC » Research » Publications at this Location » Publication #191086


item MILLER, S.
item SEMMENS, D.
item Goodrich, David - Dave
item MILLER, R.
item KEPNER, W.
item GUERTIN, D.

Submitted to: Journal of Environmental Modeling and Software
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2005
Publication Date: 3/1/2007
Citation: Miller, S.N., Semmens, D.J., Goodrich, D.C., Hernandez, M., Miller, R.C., Kepner, W.G., Guertin, D.P. 2007. The automated geospatial watershed assessment tool. J. Environmental Modeling and Software. 22:365-377

Interpretive Summary: When water quantity or water quality is of interest, watersheds are a natural organizing unit in our landscape. Watersheds gather rainfall, infiltrated water, and runoff and typically discharge that water at a stream location or into a body of water such as a lake or estuary. The pathways and processes that affect runoff generation from a watershed result from a complex interaction of the climate, topography, soils, land cover, and land use. Numerous computer models have been developed in to estimate how a watershed produces runoff from rainfall and snowfall. The KINEROS2 and SWAT models are two such examples. These models often require significant data preparation and input to use them. To expedite this task we have developed the AGWA (Automated Geospatial Watershed Assessment hydrologic modeling tool (see: This tool uses nationally available spatial data sets to setup, run, and display the results from KINEROS2 and SWAT. With AGWA and these watershed models, natural resource managers, engineers, and scientists can estimate runoff and places in the watershed that may be prone to flood damage or water quality problems. These users can also evaluate how conservation measures and changes in land use practices might improve water quality. This paper provides an overview of the AGWA tool with selected examples of its application for a variety of uses.

Technical Abstract: A toolkit for distributed hydrologic modeling at multiple scales using two independent models within a geographic information system is presented. This open-source, freely available software was developed through a collaborative endeavor involving two Universities and two government agencies. Called the Automated Geospatial Watershed Assessment tool (AGWA), this software is written for the ArcView GIS platform and is distributed as an extension via the Internet. AGWA uses commonly available GIS data layers to fully parameterize, execute, and visualize results from both the Soil and Water Assessment Tool (SWAT) and Kinematic Runoff and Erosion model (KINEROS2). These two distributed hydrologic models operate at different time scales and are suitable for application across a range of spatial scales. Descriptions of the GIS framework, hydrologic models, spatial analyses and algorithms that control the modeling process are given. Model requirements, limitations on the model applications and calibration techniques are described with examples of the use of AGWA for watershed modeling and assessment at a range of scales.