Fact sheets and reports are written by staff of EGLE's Water Resources Division, who sample aquatic macroinvertebrate and fish communities, stream habitat, and water chemistry to determine the health of our rivers and streams. Aquatic macroinvertebrates are insects and other small organisms that are excellent indicators of water quality because many live in the water all year. Some macroinvertebrates and fish are more tolerant to pollution than others. Healthy streams generally have a wide variety of macroinvertebrates and fish.

A watershed is all of the land area from which water drains into a river, lake, or stream. The most recent watershed monitoring reports are listed below by the Great Lake the watershed flows to: Lake Michigan, Lake Superior, Lake Huron, or Lake Erie. Your river, stream, or lake may be part of a larger watershed, and thus, not specifically listed. Watershed Summary Fact Sheets are also available for those watersheds sampled in 2016 or later. Additional and/or older reports may be available for your water body. If you are interested in older reports or are not sure which watershed report you need, please contact Denise Page at PageD@Michigan.gov for assistance.

An interactive map provides access to historic biological and habitat sampling locations in Michigan's streams and rivers