Atlas Data, 2006 Water Quality
Report to Congress

Wisconsin is a water rich state, with many thousands of streams stretching nearly 84,000 miles in length. Based on 1:24,000 scale USGS Topographic Quandrangle Maps (publish date varies), and GIS interpretation of those maps, Wisconsin has over 40,000 perennial stream miles and an equal number of intermittent miles.

The state's many inland lakes span over 1.2 million acres. Wisconsin also has over 1,000 miles of Great Lakes shoreline on lakes Michigan and Superior and over 5 million acres of wetlands. Groundwater in the state is similarly naturally rich, with human-induced stressors precipitating the need for increased management.

Historically the state has managed water over this expanse by divving the task among 32 basins and 330 watersheds, with the watersheds roughly equivalent to the 10-digit HUC codes. Below are the water management units. To interactively view surface water resources, see the state's Surface Water Data Viewer.

Below is a map showing waters of special interest in the state and baseline monitoring stations established up to 2005. For more information, see: monitoring data, || water quality assessments, || water quality standards.