Total suspended solids at Ford Dam

The Mississippi River provides Minneapolis with fresh drinking water. Our dogs frolic off-leash in the river near Minnehaha Creek. We go fishing in the river. We launch our canoes, motorboats and kayaks in the river. We recreate and picnic right in the shadow of the river. And when we’re done, we send all the water downstream. We cannot afford to spoil this precious resource.

Our work cleaning up the river over the last few decades is paying dividends. Total Suspended Solids (TSS) is one measure of the flow of contaminants in the river stream. TSS has been trending downward for the last four decades.
 

Data source and methodology: Data acquired from Metropolitan Council Environmental Information Management System, September 2015. Data grouped into decades, and median concentration from each decade taken and reported.

Nitrate at Ford Dam

The increasing addition of complex human-made chemical compounds into the wastewater raises new questions about the health of the river.  One contaminant trending upward is nitrate. Excess nitrate in drinking water poses health risks. Excess nitrate in the river also contributes to algae growth, which can deny the oxygen needed to support fish and other aquatic life. While Minneapolis meets current nitrate drinking water standards, the state is currently developing a nitrate standard to protect aquatic life. Nitrate can be reduced by changes to agriculture, as well as by reducing urban runoff.

Data source and methodology: Data acquired from Metropolitan Council Environmental Information Management System, September 2015. Data grouped into decades, and median concentration from each decade taken and reported.

Impairments under the Clean Water Act

Two impairments under the federal Clean Water Act continue to impact the Minneapolis segment of the Mississippi River.

The river throughout the length of Minneapolis remains impaired for E. Coli bacteria. Swimming or other contact with water impaired for E. Coli can make humans sick. The state is currently working on a plan to reduce E. Coli in this portion of the river.

Three contaminants from river water currently accumulate in the tissue of fish: mercury, PCBs, and PFOS. Because of this contamination, the Minnesota Department of Health recommends limiting the consumption of fish from this portion of the river. For healthy adults, that means just one meal a week for most fish, and in some cases even less. The recommendations for pregnant women and children are even more limited.

Data sources: Data acquired from Minnesota Pollution Control Agency (MPCA) Water Body Impairment listing (2012). MPCA has developed and submitted draft 2014 list of impairments to the Environmental Protection Agency, but those are not yet official at time of publication (December 2015). MPCA impairments are listed by Mississippi River geography: Coon Creek to Upper Saint Anthony Falls, Upper Saint Anthony Falls to Lower Saint Anthony Falls, Lower Saint Anthony Falls to Lock & Dam #1 (Ford Dam), and Lock & Dam #1 (Ford Dam) to Minnesota River