South Dakota Farmers Work to Clean Up Lake Mitchell

Jul 30, 2020

Efforts to clean up and improve the water quality of Lake Mitchell are gaining momentum thanks to collaboration between city officials, state and federal agencies, South Dakota farmers and more.  SDPB’s Lura Roti shares this story.

When Mitchell Mayor Bob Everson was a teen, Lake Mitchell was the place to be.

“It used to be the 4th of July you couldn’t get on the lake because of all the boats, or if you did, you just kind of putted around the lake enjoying the day,” says Everson.

These days the once popular lake isn’t attracting many boaters. Due to water quality issues, Lake Mitchell is now covered in algae and emits a pungent odor. Mitchell residents and business owners are concerned. So, cleaning up Lake Mitchell became a platform Bob Everson ran on when he campaigned for Mayor in 2018.

“I said we need to look at doing this as a complete project, addressing the watershed,” says Everson.

Some may think the task impossible. A watershed is an area of land water travels over or through on its way to a body of water. And Lake Mitchell’s Firesteel Creek Watershed is about 350 thousand acres. Cleaning it up has a $20 million dollar price tag. But Mayor Everson knew if he worked with the right team Lake Mitchell could once again become the boating destination it once was. 

“The more people start getting things done quicker and in a more cost-effective manner,” Everson explains.

Today, the list of public and private agencies, organizations and individuals working together to clean up Lake Mitchell is quite long. Among the first folks Mayor Everson began working with were area farmers who manage land throughout the Firesteel Creek Watershed. Seventy five percent of land in South Dakota is owned by private landowners. That makes working with farmers vital to improving water quality.

Landowners like brothers Craig and Gene Stehly. The brothers raise thousands of acres of corn and soybeans on land throughout the watershed. Avid conservationists, since the 1980s the brothers have implemented soil health practices on the land they farm. 

“We run a business to try and make money first and foremost. And we found that obviously the healthier soil is - in terms of organic matter, fertility levels your ability to hold moisture and absorb it - it is more profitable than not,” says Stehly.

Throughout the Firesteel Creek Watershed, the soil’s ability to absorb and hold water is key to improving Lake Mitchell’s water quality explains Jeff Zimprich, State Conservationist with the Natural Resources Conservation Service. 

“The best way I can describe it is that when the raindrop falls form the sky, it falls on top of a hill, and as that raindrop hits the soil it has the opportunity right then to either be infiltrated and held in the soil and slowed down or to run across the landscape. And that’s really the beginning of the water quality issues,” Zimprich says. 

Zimprich explains that some of Lake Mitchell’s water quality issues stem from too much soil or sediment flowing into the lake as well as water runoff containing fertilizer used on farm acres, residential lawns or golf courses and parks. 

Evidence of these issues began to surface in the late 1970s when an extended drought made it necessary for the city to dredge the west third of Lake Mitchell where Firesteel Creek flows into the lake.  It was shallow and filled with cattails.

“From that day on we've noticed algae blooms more I think than happened before the lake was dredged. Cattails are a very good way of removing phosphorus from the water, so that's kind of how that evolved,” Everson says.

To increase water infiltration and reduce soil erosion and fertilizer runoff on the Firesteel Creek Watershed, the Stehly brothers manage their farm acres with soil health practices like no-till planting and introducing cover crops into their crop rotation. Fifteen years ago, they also set aside 350 acres of land bordering Fire Steel Creek to serve as a natural buffer. Today on their land, nearly 50 species of native plants work to hold soil in place and filter water before it flows into Firesteel Creek. And according to water samples taken downstream from their land, the Stehly’s efforts are paying off.

Now, the Stehlys aren’t doing this at their own expense. Through collaboration and working with incentive programs from Natural Resources Conservation Service and many other agencies and organizations, the Stehlys and other farmers receive compensation for implementing conservation practices to help improve water quality.

“Without the producer participating, obviously we'd just be sitting around a table and nothing would happen. So being able to pay the producer a fair amount to do these programs is obviously the key to whether the thing is successful or not,” Stehly says.

In addition to working with farmers, the City of Mitchell purchased land on the western edge of Lake Mitchell and will partner with multiple entities to install sediment ponds and recreate a cattail wetland like the one that was there when Mayor Everson was a boy. 

Learn more about the Stehly brother’s efforts to improve soil health and water quality.