County Maps of Water Supply Watersheds in Indiana

In Indiana, 52 community water supply systems use surface water (lakes, rivers, streams) as the source of their drinking water. These systems are particularly vulnerable to contamination from certain chemicals that are transported primarily by runoff, such as atrazine and other pesticides. This site provides maps of the watersheds for each of the systems, divided by county. There are three ways to access the county maps.

1. A clickable state map, from which county maps are available for each county that intersects a water supply watershed

2. Powerpoint files, with about 10 counties included in each file. (Each file is less than 1 MB). Counties not included do not intersect any of the water supply watersheds.
1. Allen to Crawford
2. DeKalb to Fulton
3. Gibson to Huntington
4. Jackson to Monroe
5. Noble to Rush
6. Scott to Whitley

(For Educators: Link to Video explaining these maps – takes about a minute to load, and requires Windows Media Player)

3. A pdf document (approximately 5 MB) of the 52 counties

Counties that are not included do not intersect any of the water supply watersheds. A list of counties that intersect water supply watersheds is available here.

How to interpret these maps

Each county map shows the watersheds located within the county for all public water supply systems that provide drinking water from surface water sources (streams, rivers, or reservoirs). Watersheds for public water systems are important because activities or chemicals applied within them have the potential to impact drinking water quality.

Watersheds can be large or small, ranging from less than 2 square miles in areas to more than 5000 square miles. Watersheds for Lake Michigan (source water for Hammond, Lowell, Whiting, East Chicago, Indiana-American Northwest, and Michigan City) and the Ohio River (source water for Evansville) are so large that they are not included on these maps.

A county may include watersheds for communities that are not located within the county. In the map of Ripley County shown at left, drinking water supply watersheds are shown for Batesville, Osgood, and Versailles which are in the county, and also for North Vernon, Mitchell, Bedford, and Scottsburg which are located some distance from Ripley County. Activities in Ripley County can affect communities tens or hundreds of miles downstream. The smaller inset map of Indiana shows the entire watershed for more perspective.

Watersheds are often nested within other watersheds, since one water system may draw water upstream from another on the same stream or river. In those cases multiple outlines show the relationship between watersheds. For example, in Ripley County both Osgood and Versailles use Laughery Creek, with Osgood’s water intake  upstream from Versailles. Therefore the watershed for Versailles (plum outline) encompasses the entire Osgood (orange outline) watershed, plus an additional downstream area. Batesville (green outline) draws water from smaller reservoirs that are also within the Laughery Creek watershed, and its watershed is fully contained by both Osgood and Versailles. Therefore, the outline for Versailles extends all the way around the Osgood and Batesville watersheds as well. Also, North Vernon and Scottsburg-Stucker Fork watersheds lie completely within the watershed for Mitchell and Bedford, which is shown with the dark green line extending around these watersheds.

Watershed names are shown on all maps in blue, while the names of communities are in black. County boundaries, rivers, and highways are shown for reference.

For more information, please contact Jane Frankenberger, Associate Professor and Extension Specialist (frankenb@purdue.edu).