Minnesota worries about what's in the water

A stream near Minnemishinona Falls
A stream near Minnemishinona Falls is one of many tributaries that flow into the Minnesota River pictured here March 29, 2016.
Jackson Forderer for MPR News 2016

Minnesota's identity is closely linked to the state's beautiful and abundant waters. But for all its beauty, deep concerns lie just below the surface.

According to the latest impaired waters list, about 40 percent of Minnesota's lakes and streams are contaminated by pollutants.

The list, updated every two years by the Minnesota Pollution Control Agency, looks at pollutants in water around the state and determines whether they are drinkable, swimmable, fishable or otherwise safe for "beneficial uses." As of December 2016, the agency had checked about 80 percent of the state's water and found 4,607 instances where water quality standards were not being met, landing them on the list.

Sipping from any stream or lake isn't advised, as there are zero miles of drinkable water listed in the report.

But for other water activities there are 4,025 miles of streams unimpaired by contaminants and toting at least one beneficial use — with 15,494 miles impaired for at least one of the uses, according to the list.

As for lakes, the report shows there are 201,148 acres that support at least one use, and 3,712,902 acres that are impaired.

Some areas did see improvement. Since 2014, 38 bodies of water were taken off the list after meeting water quality standards.

However, 580 new instances were added just last year either because of new impairments or impairments being carried over for new assessment.

The number one pollutant — found in 36 percent of all water bodies — was mercury, found in both fish and water.

In streams, there were over 6,000 miles impaired by mercury rich fish tissue. In lakes, there were 3,559,458 acres affected.

According the MPCA, the study doesn't really show if things are getting better or worse for Minnesota's waters, since many of the bodies are being tested for the first time. Instead, it's meant to act as a baseline account for where the state is now, and a guide for where to aim water quality improvement projects.