Wisconsin
Related: About this forumFarms, More Productive Than Ever, Are Poisoning Drinking Water in Rural America
(cross posting from the Environment forum)
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One in seven Americans drink from private wells, according to the U.S. Geological Survey. Nitrate concentrations rose significantly in 21% of regions where USGS researchers tested groundwater from 2002 through 2012, compared with the 13 prior years. The greatest increases were in agricultural areas. More recent sampling shows the pattern is continuing, at a potentially greater rate. Meanwhile, more than 16% of groundwater from wells sampled between 2002 and 2012 topped the federal nitrate limit of 10 parts per million, versus 12% in the 1990s. The percentage above the limit fell slightly in the wells sampled after 2013 but remained elevated.
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In Kewaunee County, (WI) nearly 30% of private wells contain bacteria or elevated levels of nitrates, according to a state-commissioned study of samples taken in 2015 and 2016. An administrative-law judge, ruling on an objection from residents to a Kinnard Farms expansion plan, called the countys water problem a crisis and allowed the dairy to proceed on the condition it take steps to prevent contamination. Among factors producing contaminants: fewer, more-intensively worked farms, bigger cows and shifting crop mixes. Those factors have helped drive abundance in the U.S. farm economy. Corn and soybean harvests have hit records, as have pork, poultry and dairy production. Farmers and their supporters say America needs to balance environmental concerns with food security.
One farm-economy byproduct is manure, which farmers spread across millions of acres and contains nutrients such as nitrates that researchers have associated with birth defects, thyroid problems, cancer and a potentially fatal condition in infants. Another byproduct is decades-old water, laden with nitrates from a nationwide run-up in chemical-fertilizer usage, that is sinking closer to drinking water in some areas, says Bruce Lindsey, a USGS hydrologist. Runoff from fields is largely exempt from federal regulation. Many water utilities in the Midwest are struggling to pay for flushing farm runoff from their systems, say scientists and utility managers. Close to 500 public water systems in the U.S. exceeded federal nitrate limits in 2016, according to Environmental Protection Agency data. That is a sliver of the nations 151,000 water systems but a 13% increase from the portion that surpassed the limit two decades earlier.
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Scientists say groundwater contamination could be cut by reducing fertilizer use. Other land researchers and environmentalists want farmers to reduce use of underground pipes that wick water and its contents away from fields. Land researchers are urging farmers to change cultivation practices to cut water contamination. That includes sowing cover crops to hold soil in place between plantings and adding buffers of fallow land along field edges.
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Mr. Wagner has been drinking bottled water for years. In 2013, he spent $10,000 to drill a well that delivered clean water for roughly 16 months before it, too, became contaminated. His latest test, in October, showed his water remained unsafe. I was pretty naive. I thought you drilled a well and had good water, he says. Now Im stuck with a $10,000 dirty hole in the ground.
More..
https://www.wsj.com/articles/farms-more-productive-than-ever-are-poisoning-drinking-water-in-rural-america-11547826031 (paid subscription)
Bedrock called Silurian dolomite is fractured, and aquifers under it are vulnerable to infiltration of contaminants from the surface.