Clean Water

Wisconsin is rich with water resources, both above and below the ground. These resources provide Wisconsinites with a safe supply of drinking water and offer a wide range of recreational opportunities. Our water is also vital to business, supporting industries like tourism, agriculture and manufacturing.

As a result, our economy and way of life depend on keeping our waters clean and healthy. However, our waters are under threat. Polluted runoff from urban and agricultural areas dirties rivers and lakes, harming fish and other aquatic life and diminishing recreational opportunities. Excessive pumping of groundwater threatens future water supplies and harms surface waters. Even air emissions of toxic chemicals like mercury eventually make their way into our waters, harming wildlife and making some fish unsafe to eat.

Key Points

  • Clean water consistently rates as the top environmental concern for people across the state and country.[1]
  • Wisconsin has shorelines on two Great Lakes (Lake Superior and Lake Michigan) and the Mississippi River, and is home to over 15,000 inland lakes and 84,000 miles of rivers and streams.[2]
  • Fishing alone is a $1.4 billion industry in Wisconsin, with total wildlife-related recreation expenditures in the state of over $5.5 billion; aside from Florida and Michigan, more people come from out-of-state to fish in Wisconsin than any other state in the country.[3]
Clean Wisconsin's Work

Clean Wisconsin works at the state level to advocate for clean, safe and abundant water. Among other things, we helped with the passage of the Great Lakes Compact in the state, the development of Wisconsin’s policies on groundwater quality and quantity protection, and the passage of Wisconsin’s first-in-the-nation rules to limit phosphorus pollution.

We’re currently working with local partners to improve water quality and restore watersheds across the state, encouraging community water conservation and efficiency efforts, and advocating for state-level policies to protect our surface and groundwater resources.

Related Topic Pages

Polluted Runoff
Polluted runoff is rainwater or snowmelt that collects soil, nutrients, pesticides and other kinds of urban or rural pollutants as it flows over land and into water bodies. This page discusses the effects polluted runoff can have on aquatic plants and animals and water quality.

Phosphorus Pollution
Phosphorus pollution in Wisconsin’s waterways over-fertilizes aquatic plants and bacteria. It causes excessive growth of algae and nuisance aquatic plants in lakes and rivers throughout the state, including potentially toxic algae blooms. This page gives a background on phosphorus and phosphorus pollution, describing the process of eutrophication (excessive fertilization) as well as other issues in Wisconsin.

Blue-Green Algae
Blue-green algae are bacteria that often live in water and, like plants, get their energy through photosynthesis. They get their name from their color, which is noticeable when they are present in large colonies or “blooms.” These blooms worsen when human activities contribute excess nutrients to lakes and rivers. This page discusses blue-green algae, factors that affect their growth, and their potential to produce toxins and form harmful algal blooms (HABs).

Dane County’s Yahara Lakes
Dane County, Wisconsin is home to beautful lakes that are threatened by phosphorus pollution from agricultural and urban sources. Fortunately, there are several state and local groups working to clean up the Yahara Lakes and the surrounding watershed. Clean Wisconsin is currently involved in an innovative project to collaboratively address phosphorus pollution in the area. This page describes the history of the lakes and efforts to clean them up.


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Please cite this resource as: Clean Wisconsin, Inc. “Clean Water.” Clean Wisconsin Enviropedia. Retrieved from