Counties: Sullivan County
Sullivan County is in western Indiana. It is bounded on the north by Vigo County, on the west by Illinois, on the south by Knox County, on the east by Greene County, and on the northeast by Clay County.
Greene-Sullivan State Forest
Shakamak Prairie Nature Preserve
Sullivan County Watersheds
Click to enlarge
Red lines on the map depict the boundaries of 8-digit hydrologic units (one convenient definition of a watershed) as shown on this 1974 United States Geological Survey Map.
Sullivan County drains into two different 8-digit hydrologic units, each represented on the image above by an area between red lines and within the county boundary, designated by a letter. Clicking on a watershed name below will take you to separate page with more information on that watershed.