The Venture Dairy Cooperative and the Wisconsin Dairy Alliance on Monday said the recent Southwest Wisconsin Groundwater and Geology report from the University of Wisconsin shows that while there are a number of contaminated wells in that area of the state, humans are more likely to be the problem.

“In southwest Wisconsin, if your well tests positive for fecal contamination, you are nearly twice as likely to have human waste from a failing septic system than manure from a cow,” Venture Dairy Cooperative Executive Director Kim Bremmer said. “This study shows what large dairy farmers have been saying all along: you can’t place all the blame at our feet.”

The latest SWIGG report showed that of 138 wells tested, 110 came back with fecal waste samples. But researchers say 64 of those wells were contaminated with human waste, while 33 were contaminated by cows, and 13 by pigs.

Environment regulators in Wisconsin, however, continue to focus on farmers as there are more applications for larger farmers, known as concentrated animal feeding operations or CAFOs.

“Unfortunately, time and again, the ‘solution’ for cleaning up contamination like this seems to be additional regulations on CAFOs,” Wisconsin Dairy Alliance President Cindy Leitner said. “The study shows that continuing to regulate the most heavily regulated farmers means ignoring the majority of the problem. Continuing to tighten down on large farmers doesn’t improve water quality in a meaningful way and only ensures that farmers shut down or move out of state.”

Wisconsin most recently okayed a CAFO in Crawford County, in western Wisconsin, despite objections from locals who said they fear water contamination.

The Dairy Alliance and Venture Dairy Co-op say they support a “holistic approach” to cleaning up groundwater water in the state. That includes “accountability for all sizes and types of farms, but first a closer look at fixing failing wells and septic systems to target the primary problem,” the groups say.