Milwaukee may be known as A Great Place on A Great Lake, but equally important to our water system are our rivers. Most notable among them are the Menomonee, Milwaukee, and the Kinnickinnic, but the tributaries and the entire Milwaukee River Basin make up a system which nourishes a diverse urban ecology. Milwaukee Riverkeeper started as “Friends of the Menomonee River” in 1995. Today, they are the stewards of the Milwaukee River Basin and official member organization of the Waterkeeper Alliance, an international organization dedicated to clean waters.

According to the Riverkeeper website, “The Natural Heritage Inventory has documented 16 endangered, 26 threatened and 65 special concern plant and animal species and 30 rare aquatic and terrestrial communities within the basin.” And while the city of Milwaukee gets its water from Lake Michigan, 30% of the basin’s drinking water comes from groundwater, most of which originates with rainfall in one of the six watersheds. It is well known that Milwaukee has a history of industrial pollution that Riverkeeper is pledged to help clean up, but it also has a lot to protect.


Who is Milwaukee Riverkeeper?

Cheryl Nenn is The Riverkeeper – an official designation by the Waterkeeper Alliance, and lead watch-person for Milwaukee Riverkeeper. Cheryl’s life revolves around water. She earned a Master’s degree in Natural Resource Management from the University of Michigan. She has worked in New York City as a Forest Restoration Project Manager, which included protecting the Hudson River. She is an avid sailor and kayaker and is very knowledgeable of the full water cycle. What started as a discussion of the breadth of the Riverkeeper’s territory ended as a detailed discussion of public versus private responsibility for replacing residential lead pipes and chemical methods of minimizing lead in drinking water.

In her tenure, Cheryl says that the region has seen a number of notable achievements in which Riverkeeper has played a part. Riverkeeper advocated for the five-year cleanup of the Milwaukee River at Lincoln Park, upstream of the former Estabrook dam, removing 70% of known polychlorinated biphenyls (PCBs, an infamous carcinogen) in the Milwaukee River system. Riverkeeper helped create protective zoning of the Milwaukee River Greenway from North Ave. to Silver Spring Dr.  And continued vigilance and advocacy by Riverkeeper on the Milwaukee Metropolitan Sewerage District (MMSD) deep tunnel project has helped cut the average annual sewage overflows to just 5 a year, down from 50.

Our rivers closely reflect how we use the land, so Riverkeeper must be forever vigilant. Cheryl helps oversee a team of two staff and over 100 volunteer water monitors scattered from Fond du Lac and Sheboygan to Milwaukee and Waukesha, who check the rivers’ health regularly from May to October. Some direct indicators of river health are invertebrate counts (e.g. snails, worms, insects, and mussels), oxygen levels, bacteria levels, temperature, and salinity. Other indicators, such as turbidity (sediment in the water) and conductivity are subtle indicators of pollution, and are more important than you might think.

It was through testing for the presence of harmful bacteria that a ten-mile stretch of the Menomonee River was found to be contaminated. These high levels were quickly traced to sewage being part of storm water runoff – which is an ongoing problem independent of MMSD overflows – due to old infrastructure in areas such as Milwaukee and Wauwatosa. Riverkeeper has also found illicit discharges in our rivers from the presence of oil. Riverkeeper also tests for salinity year-round. Higher salinity is expected in winter months, due to road-salt, and is expected to be higher still for low-flow urban rivers (like the Kinnickinnic, because it does not so quickly wash away). But riverkeeper has found high salinity to be a year-round problem in many urban normal flow rivers, and also in rural rivers, something less understood.

What’s Next?

Riverkeeper is also very concerned with emerging issues and policy. Among these is the possibility of Asian Carp finding – and destroying – habitat in our rivers, the potential for the expansion of the Menomonee Orchard Ridge dump, and its impact on the river.  And imminent questions remain about the location of Foxconn, initially proposed for an area with extensive wetlands. Cheryl advocates the well-known principle that “The Economy is a wholly owned subsidiary of the Environment” and says that if she has one message to policy makers, it is to prevent pollution before it happens.

Riverkeeper is always looking for more volunteer water quality monitors and advocacy support, but there are other ways to get involved. Riverkeeper always asks for information from the general public on the presence of water pollution, such as surface discolorations that can result from oil spills.  You can report such pollution here. They also have an Adopt-a-River program for companies, organizations and community groups to keep the banks of their rivers clean. And finally, they orchestrate a large river cleanup every Spring. Cheryl invites you to be a part of a living breathing community of residents fighting to keep our rivers clean.

Casey S. Schroeder is a regular contributor to MASA. More of his work can be found at

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