Hundreds of fish killed by manure runoff in Monroe County

Manure runoff from a dairy farm in Monroe County killed hundreds of fish in nearby waterways, according to the Wisconsin Department of Natural Resources.

The agency first received notice of the spill Saturday from a call to its violation hotline. Ben Uvaas, agricultural coordinator for the DNR, said a conservation warden confirmed dead fish in Spring Valley Creek.

Uvaas said the runoff came from fields where liquid manure had recently been injected by Brueggen Dairy Farm southwest of Norwalk. He said it’s believed that intense rainfall of an inch or more within a half-hour span on May 14 caused the release into Spring Valley Creek, Moore Creek and the Kickapoo River.

“Preliminary numbers have dead trout in the low hundreds and many other dead non-trout species of fish were collected for identification,” Uvaas said.

Preliminary figures don’t reflect the entire stretch of roughly 8 miles of creek that were impacted by the spill. Uvaas said about 11,500 gallons of manure per acre had been injected into nearby fields before the rain event, but he said it’s almost impossible to estimate how much manure or manure-laden water may have flowed into waterways.

Brueggen Dairy Farm is a medium-sized farm with nearly 600 cows. The farm is not considered a large livestock farm or concentrated animal feeding operation because it has less than 700 cows or 1,000 animal units.

“Despite all our efforts to find the best time to apply (manure), Mother Nature is unpredictable,” the farm’s owner Randy Brueggen said in a statement.

“We as a dairy farm know how valuable this resource is, which is why we utilize incorporation practices in an intentional, safe and compliant manner,” Brueggen continued. “We strive to utilize our organic fertilizer over synthetic fertilizer for our crops. Our group’s farming practices always prioritize conservation. We want to sustain the land, so the land sustains us.”

Bob Micheel, director of the Monroe County Land Conservation Department, said Brueggen was visibly upset and stressed over the spill. Micheel added that Brueggen was following the farm’s nutrient management plan.

“He’s doing all the things that we would recommend,” Micheel said. “These weather patterns of the last 15 to 20 years have changed what’s going on out there. It can blow up one farm situation overnight, and that’s what happened.”

Uvaas said cleanup and containment of the spill in Wisconsin’s Driftless Area is extremely difficult due to the region’s steep slopes and the speed of water during intense rainstorms, as well as limited access to waterways for portable pumps or vacuum trucks for cleanup.

“Once it’s gone, it’s gone. There’s not much to do, especially when those brief intense rainstorms boost manure off the field and get it into waterways,” Uvaas said.

Wisconsin is seeing more frequent, intense storms that can lead to nutrient runoff due to climate change, according to the latest report from Wisconsin’s Initiative on Climate Change Impacts. Southern Wisconsin has seen the highest increase in precipitation.

Peg Sheaffer, spokesperson with Midwest Environmental Advocates, said it’s likely that manure runoff events will become more common with the increase in extreme storms.

“One thing we can do is to make sure that the DNR’s manure storage and spreading regulations are based on the most up-to-date information about rainfall intensity and frequency,” Sheaffer said. “I think from a regulatory standpoint, agencies like the DNR can no longer rely on historical precipitation data like they used to.”

Manure storage requirements for large farms often reference 25-year, 24-hour storms that are more common and less intense, but regulations allow design of such structures to be based on more recent rainfall data.

As the climate changes, Sheaffer added that dairy farms are expanding in size and generating manure that’s increasingly concentrated on fewer farms. As farms consolidate, she said there should be serious conversations about the regulatory approach to smaller and medium-sized farms that aren’t regulated like CAFOs.

“Those CAFO regulations don’t apply to the farm that we’re talking about here,” Sheaffer said. “In this particular case, I think it’s definitely time that we should be taking a broader look.”

Uvaas said even the latest best management practices that farmers adopt to keep manure and fertilizer from running off fields can fall short during intense storms. He added farms that use nutrient management plans in line with state regulations avoid spreading manure prior to forecasted rainstorms that are likely to cause runoff.

Both Uvaas and Micheel noted that the farm’s manure application rates were considered low disturbance.

The DNR is working with the farm and county to inspect manure application to fields, as well as anything that can be done to prevent future manure runoff. Micheel said the only thing he may recommend is adding contour strips every 100 feet that alternate between corn and perennial crops like hay to keep water from running off fields on steep slopes.

Given significant impacts to waterways, Uvaas said there’s typically enforcement action taken, but the agency is still gathering information on the best response.

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