Purdue Extension Water Quality Home

Geographic Information System (GIS) Tools for Watershed Management

Web-Based GIS Tools for analysis of hydrology and water quality, developed by Dr. Bernie Engel and his graduate students and staff.

Online watershed delineation: This tool will calculate the watershed area draining into a point that you have selected on an interactive map. It is available for the 6 states in EPA Region 5 (Indiana, Illinois, Wisconsin, Minnesota, Michigan, Ohio). Once you have obtained a watershed using the watershed delineator tool you can: estimate impervious area of your watershed, run L-THIA, or download the data to your computer.

Long-Term Hydrologic Impact Assessment (L-THIA), an online tool to assess the water quality impacts of land use change.

SedSpec tools for designing runoff and erosion control structures, based on event-based hydrologic analysis

Web-Based Hydrograph Analysis Tool (WHAT), which separates hydrographs into runoff and base flow. This page also provides a way to select USGS gauging stations using an interactive map, and calculate statistics of model simulations.

Web-based National Agricultural Pesticide Risk Analysis (NAPRA). Online estimates of pesticide and nutrient runoff and ground water leaching, using the GLEAMS model and crop management inputs.

More tools are available at the Web site of the Midwest Partnership for Watershed Management Decision Support Systems. The goal of this site, which is sponsored by EPA Region 5 and land-grant universities is to develop, promote, and disseminate web-based spatial decision support systems to help manage watersheds in the Midwest.

Obtaining Indiana GIS Data

A GIS Atlas for Indiana, from Indiana Geological Survey

Purdue Center for Advanced Applications of GIS data download site

Indiana Spatial Data Portal: Data storage and retrieval of Indiana GIS data, from Indiana University.

County GIS Atlas CD-ROMs. More than 50 Indiana GIS layers, clipped to the county with a 3-mile buffer from Purdue University. The CDs are available for purchase for $9 each and provide an easy way to access available data in a uniform projection system.

Indiana Digital Orthophotos from 1998-9 on CD-ROM from Purdue University. See map for specific ordering information.  

Obtaining National GIS Data
You can also access Indiana GIS data through national GIS data servers. Two excellent ones are:

The National Map is an interactive map service, produced by a consortium of Federal, State, and local partners who provide geospatial data to enhance America's ability to access, integrate, and apply geospatial data.

is part of the Geospatial One-Stop E-Gov initiative providing access to geospatial data and information. 

Updated August 23, 2005
Purdue Extension

For questions regarding the content of this site contact Brent Ladd. For information on the Purdue Extension Water Quality Program contact
Jane Frankenberger, Agricultural and Biological Engineering, Purdue University
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