Natural Resources Inventory and Analysis Institute

Technical Resources

SSURGO County-Level Soils Data with the SWAT Watershed Model

The Soil and Water Assessment Tool (SWAT) is a watershed-scale model used to predict the effects of management decisions on water quality and quantity, sediment, nutrient, and pesticide yields on large and small river basins. The model is available with Arc-View, GRASS, or Windows interfaces. It is distributed widely on the Web and is included in the new EPA ‘Better Assessment Science Integrating point and Nonpoint Sources’ (BASINS) CD. This study developed SWAT models of five small watersheds in Johnson County, Iowa for use by the local conservation district and USDA field office. The highlights of this study include using the county-level NRI data to develop annual land cover layers for the SWAT model; and using the more detailed Soil Survey Geographic (SSURGO) Database with SWAT instead of the standard SWAT method using the State Soil Geographic (STATSGO) Database. This study is a corroborative effort of NRCS, ARS, and Texas A&M University staff using the 1999 Arc-View interface for SWAT (AvSWAT).

A revision/update to this procedure is available at SSURGO SWAT 1.0 EXTENSION, developed in 2003 by Peschel, J.M., P.K. Haan, and R.E. Lacey.

The following documents require Microsoft Word, Adobe Acrobat, or a compression utility such as PKZip.

Description	Location
New Procedure developed in 2003	A SSURGO Pre-Processing Extension for the ArcView Soil and Water Assessment Tool 2003.ASAE.032123.paper.pdf(630 KB)
Poster 1MB	SSURGO County-Level Soils Data with the SWAT Watershed Model swatsurgo6.ppt (1733 KB)
Instructions	Creation of Johnson County SWAT SSURGO Soil Input Dataset
Conversion Database	AvSWAT SSURGO Conversion Database swatsurgoconver.zip (504 KB)
Readme files	Instructions to Load and use the Johnston County SWAT datasets from CDs instrswatdata.doc (25 KB)
EPA BASINS	http://www.epa.gov/ost/BASINS/
GAP	http://www.ag.iastate.edu/centers/cfwru/iowagap/
NRI	http://www.nrcs.usda.gov/technical/NRI/1997/intro.html
LANDSAT	http://geo.arc.nasa.gov/sge/landsat/landsat.html
SSURGO	http://www.ftw.nrcs.usda.gov/ssur_data.html
STATSGO	http://www.ftw.nrcs.usda.gov/stat_data.html
SWAT	http://www.brc.tamus.edu/swat/
AvSWAT	http://www.brc.tamus.edu/swat/swat992.html

Authors

David Buland	USDA/NRCS, Natural Resources Inventory and Analysis Institute
Erda Wang	Blackland Research Center, Texas A&M University
Bob Dayton	USDA/NRCS, Natural Resources Inventory and Analysis Institute
Glenn Lawson	USDA/NRCS, Natural Resources Inventory and Analysis Institute
Mauro DiLuzio	Blackland Research Center, Texas A&M University

The new NRCS e-Field Office Technical Guide can be accessed via the NRCS National Office Web Site at http://www.nrcs.usda.gov/technical/efotg/ .

Please send back feedback on this WEB site, data calculations, or data distribution methods to David Buland.
01/23/2003 This website is sponsored by:

The Natural Resources Inventory and Analysis Institute
Natural Resources Conservation Service
United States Department of Agriculture

Blackland Research Center
Texas A&M University
Temple, Texas 76502-6712

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