BY DEANNA BOSS
After discovering a flood in my basement in June, and more water after each rainfall, I focused on finding a solution. Once I realized the problem could extend beyond my dwelling is when the real work began. Why is my basement taking in water when it never has before? Why are there duck ponds where kids used to play? Why does it look like Lake Nokomis is about to spill over its banks?
Here are some things I discovered. There is no one entity that oversees the water, lakes and parks in Minneapolis. It is a combination of the City of Minneapolis, the Minneapolis Park and Recreation Board, the Minnehaha Creek Watershed District and the Minnesota Department of Natural Resources. If you have a problem, to whom would you reach out for assistance? The only correct answer to this is all of them.
After corresponding with my City Council member (John Quincy), my park commissioner (Steffanie Musich) and the director of surface waters and sewers for the City of Minneapolis (Katrina Kessler), my email trail ended with the project and land manager of the Minnehaha Creek Watershed District (Tiffany Schaufler).
I reached out to Ms. Schaufler asking for more details on how the weir at Lake Nokomis operates, and why, when the water level is so high, the weir wouldn’t be lowered.
After she shared a general history of Lake Nokomis to open her response I finally got the clarity I was seeking:
“We need to look beyond the borders of Lake Nokomis itself to understand how the hydrologic system works. Lake Nokomis has a surface area of 200 acres and is located in Minneapolis. However, its watershed area (the area that drains to Lake Nokomis) is 2,634 acres and includes areas within Minneapolis, Richfield, Fort Snelling and the Minneapolis-St. Paul Airport. In 2016, the total precipitation to date has been 18.5 inches. The average precipitation from January-July is 17.87 inches. Between January-July the total in 2013 was 24.3 inches; 2014 was 28.09 inches; and 2015 was 19.05 inches. We are having a relatively average year for rainfall; however, the area has received several large rain events (greater than 1 inch of rain) which can cause local high water problems as the entire 2,634 acres of the Lake Nokomis watershed drains into the lake. For example, from June 12-14 the area received 2.88 inches of rain; however, this caused the Lake Nokomis water level to rise 5.4 inches as the entire watershed drained into the lake. These large rain events, coupled with the naturally wet soils around Lake Nokomis will result in saturated soils as you have observed.
“The goal of the Nokomis Weir is to not hold water in Lake Nokomis but to rather prevent polluted water from entering it from Minnehaha Creek. However, the weir was also designed to allow Lake Nokomis to drain into Minnehaha Creek if Lake Nokomis is experiencing high water issues. This is where the Nokomis Weir Operating Plan comes into play.
“The DNR has established an Ordinary High Water Level (see more at http://bit.ly/MNDNRhighwaterlevel) for Lake Nokomis at elevation 815.4 feet. The Nokomis Weir Operating Plan allows for the stop logs to be removed:
“IF the Lake Nokomis level is at or above 815.4 for two weeks and/or
IF there are high-water related problems affecting MPRB infrastructure;
AND The Minnehaha Creek level is measured using the survey gauge and is found to be below elevation 815 and is at least 1 foot below the measures level of the Lake Nokomis survey gauge (Example: If the Lake Nokomis level is at 815.82 then the Minnehaha Creek level must be at or below 814.82);
AND There is no precipitation predicted for at least 48 hours;
AND MPRB staff has notified MCWD staff of the proposed stop log removal;
AND MCWD staff has agreed not to change the discharge rate at the Gray’s Bay Dam until the stop logs have been reinstalled
“The stop logs are then to be reinstalled and the Nokomis Weir closed when Lake Nokomis reaches the elevation of the weir, which is 815.1, or precipitation is predicted within 24 hours.”
Overwhelmed by what has to happen in order to get some water out of Lake Nokomis and perhaps alleviate some of the flooding in the surrounding turf and park areas? Me too. Still worried about the flooded basements in homes close to Lake Hiawatha? Me too. Wondering what to do? First, if you haven’t yet, take this survey—bit.ly/NokomisHiawathaFlooding—and sign up to stay in touch so we can work together as a community to get resolutions to problems threatening our homes and parks. Next, let’s continue to ask questions of those in charge and what they are willing to do to protect our neighborhoods. I discovered the City of Chicago has an entire initiative (http://bit.ly/ChicagoBasementFlooding) to work with homeowners who are experiencing flooding in their basements because the city’s aging sewer infrastructure isn’t able to handle the heavy rains. I know with enough concerned residents and park users Minneapolis could follow this lead in protecting this community.
Survey will be available online until Sept. 30, 2016: bit.ly/NokomisHiawathaFlooding.
