Milwaukee's rivers are increasingly popular. Here's the newest report card on the quality of the water

The Milwaukee Riverkeeper has released its annual report card on the water quality of the Milwaukee, Menomonee and Kinnickinnic rivers. 

Again, it’s not great news. But there are signs for optimism. 

The grade: For 2017, it’s a C-minus. That’s up from a D-plus in 2016. 

Why you should care

The rivers have become increasingly popular over the past decade as more businesses and people have located or made their homes near them, especially downtown along the Milwaukee River. Kayaks and touring boats have proliferated in recent summers. 

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Also, billions of dollars have gone into cleaning up the rivers. The Milwaukee Journal Sentinel reported in 2014 that more than $5 billion had been spent by government agencies since 1980. But like many urban rivers systems, many sections are not meeting standards for safe swimming. 

What about the objectivity of the report?

The report card isn’t subjective. Every year, Riverkeeper analyzes data collected by more than 100 of its volunteers who take water samples in different locations and add the data from samples from agencies, including the Wisconsin Department of Natural Resources and Milwaukee Metropolitan Sewerage District. 

Riverkeeper takes those results — like temperature, dissolved oxygen and chlorides (a measure of road salt) — and compare them to state and federal standards to see how often spots on the rivers are in compliance.  

The study does not take into account so-called legacy contamination from industrial chemicals like polychlorinated biphenyls, which can affect the immune and reproductive systems of humans. Major recent cleanups have addressed problems in the Milwaukee River and Lincoln Creek and in Cedar Creek in Cedarburg.  

Are there any trends? 

The grades have changed little over the last eight years and that’s been frustrating for many people, according to Cheryl Nenn, whose title is "riverkeeper" and oversees the report. But she noted that it took decades of industrial and runoff pollution to create the problem; in turn, it will take years to see a big improvement.

Last year, however, there were improvements in two key pollution measures: algae-causing phosphorus and bacteria. Riverkeeper attributed it to a relatively dry year that meant less dirt, animal waste and fertilizer running into the basin. 

Where are the biggest problems? 

As in other years, the Kinnickinnic River had the poorest water quality. It received a grade of D. Only slightly better was the Menomonee and the south branch of the Milwaukee rivers, both of which earned a D-plus. The south branch of the Milwaukee starts roughly in southern Ozaukee County and flows to Lake Michigan. 

And the best water quality? 

The east and west branch of the Milwaukee River, in Dodge and Fond du Lac counties, where there is less development.

What’s new this year?

This year, Riverkeeper surveyed mussel populations, which can help clean rivers by filtering contaminants. Of the 51 sites surveyed, 18 had live mussels. At another 24 sites, shells were found, but no live mussels.

The most mussels were found in Cedar Creek, northwest of Milwaukee, and in the south branch of the Milwaukee River.

Also, Riverkeeper worked with Ryan Newton of the University of Wisconsin-Milwaukee’s School of Freshwater Sciences to look for sewage contamination by analyzing the DNA signatures of bacteria in the water.

Newton found varying degrees of contamination from the sewage system, with the worse being at Wilson Park Creek, a tributary of the Kinnickinnic at South 20th Street and Wilson Park Drive.

Two spots where little sewage contamination was detected were Covered Bridge Park on Cedar Creek in Ozaukee County and Indian Creek where it flows into the Milwaukee River in River Hills.

What to look for in coming years    

The removal of the 80-year-old Estabrook Park dam this year is expected to improve conditions in the Milwaukee River, south of Lincoln Park.

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Also, the U.S. Environmental Protection Agency this year approved a long-term plan that essentially puts the river basin on a pollution diet by requiring reductions of phosphorus and total suspended solids like silt that pollute the water.