Manure Spreading, Runoff Under Fire

Proposed DNR changes specify bedrock, groundwater protection; accepting public comments until October 4


MADISON — When one-third of Kewaunee County’s private wells tested positive for bacterial contamination in 2014, some pointed to a massive cattle population and others pointed to faulty septic systems. Ongoing study has linked manure from Concentrated Animal Feeding Operations (CAFOs) to the county’s polluted groundwater and has influenced proposed revisions to the Department of Natural Resources’ (DNR) manure spreading requirements.

Kewaunee, Brown, Door, and several other counties along Lake Michigan feature porous Silurian bedrock at various depths. Manure spread on more shallow soil can quickly breach groundwater with nitrates, e. coli and other harmful pathogens. If implemented, proposed changes would differentiate discharge regulations by underlying geology rather than blanket requirements which currently exist, the first such distinction in the DNR’s history.

Showing the fingerprint of Kewaunee County’s water crisis, well contamination from land spreading on Silurian bedrock could lead to legal penalties or revocation of a farm’s permit to spread. Moving forward, nutrient management plans would need to include identification of Silurian areas and the methods which the farm intends to treat them.

Clean Wisconsin, the Clean Water Action Council, Midwest Environmental Advocates, and the Wisconsin League of Conservation Voters have lobbied for tougher spreading regulations on CAFOs amidst the growing net of contaminated wells and said in a joint statement to the DNR, “Reducing well contamination in parts of WI exceptionally vulnerable to groundwater pollution from surface sources like livestock waste will reduce health risks and health costs for Wisconsin citizens, save taxpayers and citizens money on well replacement or water filtration systems, and improve real estate values and quality of life for all residents in vulnerable areas of the state regardless of whether their well has been contaminated to date.”

About 1% of the state’s 35 million acres of land will be affected by the most drastic rule changes pertaining to bedrock with 2 feet or less of soil cover. The Dairy Business Association (DBA), often the target of activist fire, claims the rule will have unintended consequences on the land market and adversely affect smaller farms while incentivizing poor practices by the financially strapped.

“…this rule will force land values and rents in regulated and neighboring areas to rise significantly. The rent increases will be greatest for land with deeper soils. At the same time, land with shallow soils could be less expensive to rent if this rule is implemented. Farmers that own a lot of land with shallow soils will likely have to rent more land at inflated prices while they see their existing farm devalued,” the DBA posed in a written question.

The DNR did not speculate if crop land would be taken out of production or what, if any, effect the rule change would have on land values.

A full overview of the rule changes and the Economic Impact Analysis is available through the DNR at and the Department will be accepting public comment until October 4. Comments can be made to the DNR via email at