Livestock operations in Wisconsin create more waste than people do, but they are barely regulated and often uncontained. AT RISK Livestock waste contains high levels of contaminants such as nutrients and pathogens. When those contaminants get into our drinking water, they make people sick. High levels of nitrogen leaching into drinking water supplies increase the risk of spontaneous miscarriages and blue-baby syndrome, which can cause death in infants. A recent study by the University of Wisconsin Extension found that in some watersheds in Wisconsin, including the Mendota Watershed in Dane County, almost 50 percent of private wells contained unsafe levels of nitrates.
Animal waste poses a human health risk due to pathogens, such as cryptosporidium.
In 1993, cryptosporidium in Milwaukee's drinking water supply made 400,000 people sick and led to the deaths of more than 100 people. High levels of contaminants from manure in waterways kill fish and other aquatic wildlife. In June of 1998, runoff from a large dairy near Cleveland in Manitowoc County created a plume of contaminated water that stretched a quarter-mile into Lake Michigan, killing hundreds of game fish as well as thousands of minnows and other smaller fish. In May of 1999, liquid dairy manure and contaminated milk were dumped into the South Fork of the Baraboo River, killing thousands of fish and fouling between five and six miles of the trout stream. In 1991, an Iowa County cattle feedlot operator sprayed between 20,000 and 30,000 gallons of liquid manure into a nearby creek, polluting 13 miles of river and killing tens of thousands of fish.