The Minnesota Pollution Control Agency recently released its annual list of waterways that are "impaired" due to pollutants or other problems that threaten fish, plant life or public health.
The list is a federal environmental reporting requirement and part of a 10-year effort by the state to assess all 80 of its watersheds. That inventory, about halfway complete, has found impairments in roughly 40 percent of the bodies of water that it has checked statewide.
Hundreds of lakes and river segments, including two Lake Superior beaches, were added to the list this year. Read the Star Tribune's story about that here.
Mercury is the leading contaminant, accounting for one-third of the listings. Nutrient imbalances such as excessive phosphorus are the second most common problem.
More information about the impaired waters list is available on the MPCA website.
In the map below, either use the plus/minus buttons in the upper right to zoom in or use the search box to type in an address or city name, which will zoom the map to that area. Hover over any impaired waterway to see the pollutant or stressors that have been identified.
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