Published 6:32 pm Friday, September 24, 2021
BWSR, Mower SWCD discuss flood control, water quality projects during Climate Week
This week marked Climate Week in Minnesota, a time meant to draw attention to the impact of climate change. On Thursday, members of the Minnesota Board of Water and Soil Resources (BWSR) and the Mower Soil and Water Conservation District met at Dexter Dam 2 in Dexter Township to discuss flood mitigation efforts that not only reduce water flow, but improve water quality.
“It’s a worldwide challenge that we’re all up against,” said BWSR Executive Director John Jaschke. “The Governor has a climate subcabinet established through an executive order that includes agencies like the Board of Soil and Water Resources. Among the things that entails is to look at ways to deal with the climate challenges we’re given. One of those is to deal with our water, especially water coming at rates and volumes we haven’t seen previously. We had a dry summer this year, but in years gone by and in years to come, we’re certainly going to see that again.”
The site at Dexter Dam 2 includes a water storage structure functioning along a 2,000 foot-long embankment that is designed to reduce high water flow from significant rain events.
It was constructed through a partnership with the Mower SWCD, the landowner, Barr Engineering, Griffin Construction, Mower County, DNR Dan Safety staff, and the Cedar River Watershed District, who received a $606,850 Clean Water Fund Targeted Watershed Grant from the BWSR in 2014 to support the project.
This year, the Minnesota Legislature passed a law requiring the BWSR to develop a program to provide financial assistance to local government units to control water rates and/or volumes to protect infrastructure, improve water quality and related public benefits, and mitigate climate change impacts. The Legislature also appropriated $2 million to develop the program.
“With the new project we’re working on with the $2 million the Legislature appropriated, we’re going to be helping local units of government construct projects like this or any other storage-type projects,” said BWSR Chief Engineer Rita Weaver.
“With the local participation, we see this as a really important acceleration point for doing these kinds of projects all over Minnesota, particularly in the agricultural parts of Minnesota where we’ve had altered landscapes from ditching and tiling,” Jaschke said.
Dexter Dam 2 is located near Dobbins Creek, a location that is one of the fastest to spike during big rain events.
“We’re trying to slow the water down,” said Mower SWCD Project Manager Cody Fox. “It’s not for everywhere; we’re trying to select areas through different plans we had developed and find the right places to do these projects and make the biggest impact.”
Fox said that there are 14 such sites in Dobbins Creek and that flow reduction is over 10% in a 100-year rain event. Mower SWCD is aiming for 20% reduction.
“That might be a little lofty, but we’re going to continue to move forward in finding good projects and hopefully we can get close to the goal and show the public what it means to them when we have these rain events,” Fox said. “Fortunately, floods don’t come around everyday. But when they do, that’s when people are really going to notice these upstream projects.”
Weaver explained that the idea for the design of these projects is to back water in the area and then slowly release it downstream through the outlets.
“The benefits to that, in addition to the flow reduction, is that as the water sits here, the sediments settle out, so we’re going to get less sediment in the flow that goes downstream,” she said. “Since we have lower flows downstream, we’re going to see less erosion downstream. We can also calculate how much sediment removal we can expect.”
“Water is slowed and the channel can be restored, and in some cases we get water quality benefits and habitat benefits because of that,” Jaschke said.
Mower County resident Kevin Kiser has a similar project on his land not too far from Dexter Dam 2. He noted that those involved in the project were professional and doing good work for the farmers.
“I think everybody involved should be proud of these projects and how they’re going to help businesses in the area,” he said. “They do everything they say they’re going to do and it’s been great to work with them.”
“We want to do projects that are fair to the landowner, but also accomplish the values and goals that we’re shooting for,” Fox said. “In my opinion, and I think in the landowners’ opinion, we’ve hit all of those marks for the most part. We’re improving water quality and reducing flood risk downstream to houses, cropland and roads.”