The Rock River is divided into the Upper and Middle Rock River watersheds. The Middle Rock River basin encompasses the Yahara River and much of the metropolitan Madison area. The Upper Rock River basin includes the Crawfish River subwatershed, with a majority of the area draining to its Maunesha River tributary.
Basin Description
The Middle Rock River basin covers the central portion of Dane County. The Yahara River and its chain of lakes (Mendota, Monona, Waubesa, and Kegonsa) are central to Madison's identity. Urban and agricultural runoff water quality issues are prevalent in the basin, with the conversion of agricultural lands to urban development shifting stressors on water resources. Increasing developed areas leads to increasing runoff volumes from impervious surfaces. Stormwater regulations are key in managing excess runoff and reducing the risk of flooding downstream. Groundwater contamination and withdrawal within this dense urban area also place pressure on groundwater resources. In the central sewer service area, encompassing the chain of lakes and metropolitan Madison, the Madison Metropolitan Sewerage District manages wastewater. Effluent is pumped into Badfish Creek in the Yahara basin and into Badger Mill Creek in the Sugar River watershed.
The Upper Rock River basin, in the northeastern corner of Dane County, is primarily agricultural. Many streams have been ditched and straightened and many wetlands have been drained to accommodate farming. Principle crops include corn, soybeans, and alfalfa. Agriculture can be linked with increased nutrient concentrations in surface water.
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TMDL
The Rock River is polluted, and the region is implementing a plan for improving the river's water quality. The Rock River Recovery is the project for the river's total maximum daily load (TMDL) of pollutants, as determined by the US EPA and WDNR. The goal of the TMDL is to restore the designated uses of impaired waters within the Rock River basin.
To see water quality goals and pollutant load allocations within the watershed, visit the Wisconsin DNR Watershed Restoration Viewer. This interactive map shows targets for total phosphorus (TP) and total suspended solids (TSS) within the watershed. It also shows the watershed's impaired waters. Click on an impaired water to see its reason for impairment.
Starkweather Creek
The Capital Area Regional Planning Commission, in collaboration with many local partners, is working to reduce chloride use in the Starkweather Creek watershed. Chloride concentrations in this urban creek, which flows into the northeastern side of Lake Monona, have increased over the past 30 years. This project comprehensively examines chloride use in the watershed, primarily salt used in water softeners and in winter snow and ice removal. Since chloride is not degraded or consumed in the environment, the most efficient way of decreasing chloride in our water resources is to strategically reduce salt use.
Learn more about the project and how to reduce salt use here.

Waubesa Wetlands
In 2017, the Capital Area Regional Planning Commission, in collaboration with WDNR, convened a Technical Advisory Committee to conduct a comprehensive study of the Waubesa Wetlands on the southern toe of Lake Waubesa. An element of this study was completed by Water Resources Management graduate students from the Nelson Institute for Environmental Studies at UW-Madison. Their project, Assessing Land Use Impacts and Promoting Community Engagement in the Waubesa Wetlands Watershed, was completed in 2019.
Learn more here.
Friends Groups
The Rock River Coalition provides the public with the opportunity to work together to improve environmental, recreational, cultural and economic resources within the Rock River basin. They have a volunteer water quality monitoring program and host a yearly event connecting people from across the watershed.
The Clean Lakes Alliance is committed to the improvement and protection of lakes, streams, and wetlands of the Yahara River watershed. The group raises awareness about watershed issues and procures funding for protecting water resources. The Alliance also hosts various annual events and volunteer days to encourage the community involvement with the lakes. One such event is Yahara Lakes 101, a series of educational talks focusing on issues impacting the lakes.
Find other groups active in the Lower Rock and Upper Rock watersheds.