The stormwater pond at the Emerald Sky Dairy in St. Croix County that was polluted after a 2016 manure spill. A new survey finds that waste produced in the St. Croix River watershed is as much as if more than 3 million people lived there. (Wisconsin DNR photo)

The waste produced by livestock in the St. Croix River watershed is equivalent to 3.25 million more people living in the region, according to a study conducted by a retired University of Iowa professor on behalf of local clean water activists. 

The study, conducted by Dr. Chris Jones, who studied water quality and agriculture at Iowa, totals the number of beef cattle, dairy cows, hogs, chickens and turkeys across the river’s watershed in Minnesota and Wisconsin, calculates the amount of waste those animals excrete in terms of nitrogen, phosphorus and solids. It also  projects  how many  humans it would take to produce that much waste. 

“Some of these nutrients from the manure get into our streams, we know that,” says Jones, who has authored a book about the effect of factory hog farming on the water in his home state. “And so, since the waste is not treated, and since the distribution of it on the fields is not very regulated … this volume of waste certainly makes the river and its tributaries more vulnerable to nutrient groups.”

In recent years, western Wisconsin has become the site of the state’s most intense fights over factory farming. Most of the state’s largest farms, known as concentrated animal feeding operations (CAFOs), have been in the eastern part of the state. But large agricultural companies have been working to expand factory farming operations across western Wisconsin’s Driftless Region and the St. Croix watershed. 

That effort to expand has sparked a growth in local opposition. A number of communities have worked to pass local ordinances regulating how and when a factory farm can be built or expanded within their borders. Industry groups have filed lawsuits to block those efforts. 

Community members have also worked to stop or change permitting decisions by the state Department of Natural Resources for the expansion of factory farms. 

“I think it’s very important for citizens to realize that the counties and other local governments retain some power in being able to zone their land for the construction of these CAFOs because, as I said in Iowa, when the counties lost control, that’s when the big expansion occurred,” Jones says.

Despite local opposition, CAFOs have continued to grow, causing increased amounts of nutrients in the local water systems. Runoff and manure spills have caused massive fish kills in local streams, beaches have regularly been closed due to excessively high levels of pollutants and the groundwater — the sources of drinking water for most rural residents — has been found to contain high levels of nitrates. 

The St. Croix River has been part of the National Park System as a Wild and Scenic River since 1968 and listed as an “impaired water” by the Environmental Protection Agency since 2012. 

According to Jones’ study, most of the livestock within the watershed is raised on the Wisconsin side of the border. The waste created by just the livestock in Barron County is equivalent to 1.7 million extra people. The livestock waste in St. Croix County is equivalent to 911,000 more people.

The population of Barron County is about 46,000 and of St. Croix County is about 96,000, according to U.S. Census data. 

Jones says it’s within the capabilities of the regulating agencies and university systems in both Minnesota and Wisconsin to calculate the exact number of livestock the watershed is capable of enduring. He says they should do that, because the industry won’t. 

“This is an approach the state should think about in regulating these areas on a watershed by watershed basis, based on what we assume they can endure,” he says. “And that ought to be done for the Saint Croix to protect it.”

He doesn’t expect the St. Croix River’s designation as a national waterway by itself to influence the agriculture industry to change its practices.

“We have evidence here in Iowa, but any special status that the streams have is not going to affect decision making on the ag side, it’s just not,” Jones says. “So the state’s got to try to get in front of this and get their arms around it, because once the horse leaves a barn, it’s too late.”