Well Water in Kewaunee County, Wisconsin

What was found: a countywide test, an EPA petition, and a state workgroup

In June 2013, a countywide private-well testing effort in Kewaunee County found that 30.85% of tested wells had levels of nitrate and/or E. coli bacteria exceeding state and federal health standards -- a strikingly high failure rate for a single round of testing, and one that made national news. Roughly 70% of the county's residents rely on groundwater, drawn from private wells, for their drinking water, so a contamination rate at this scale is not a marginal concern affecting a handful of properties.

That finding led directly to formal action: in October 2014, residents and environmental groups petitioned the U.S. Environmental Protection Agency to use its emergency authority under the Safe Drinking Water Act to investigate the source of the contamination and require the state to act. The Wisconsin DNR subsequently convened a multi-stakeholder Groundwater Collaboration Workgroup, which issued its final report in June 2016 after input from environmental groups, agricultural interests, and affected residents. The EPA maintains an ongoing Kewaunee County Groundwater program page tracking developments.

Why: karst bedrock, septic systems, and manure together

Kewaunee County's contamination pattern traces to a combination of factors common across the county. Much of the county's bedrock is shallow, fractured karst -- often just a thin layer of soil over cracked dolomite -- which lets surface contaminants reach groundwater quickly with little natural filtering. Layered on top of that geology is one of the state's highest concentrations of dairy CAFOs (14-17 permitted large operations recorded at different points, with tens of thousands of animal units combined) applying liquid manure to farmland across the county, plus the ordinary distribution of private septic (POWTS) systems found in any rural county. Any one of these factors alone would be manageable; together, on this specific bedrock, they produced a measurably elevated contamination rate.

The Well Compensation Grant Program: help if your well tests contaminated

Wisconsin's DNR-administered Well Compensation Grant Program provides financial assistance to eligible landowners or renters to replace, reconstruct, or treat a contaminated private water supply serving a residence or livestock. To qualify, the water supply generally must be documented as contaminated based on DNR or Department of Health Services advisory letters, or testing exceeding state or federal standards, and household income limits apply (a $65,000 prior-year household income cap was cited in program materials, though eligibility rules can change). Kewaunee County residents have specifically been able to draw on this program given the county's documented contamination history, and the county's own Land & Water Conservation Department maintains information on this and other financial-assistance options (including a Lakeshore Community Action Program and USDA home-repair loan/grant programs).

What to actually test for and do

1. Test any existing well for nitrate and E. coli/total coliform bacteria at minimum -- the two parameters found elevated in the county's 2013 testing round -- through a certified lab, rather than relying on a seller's past test result, since groundwater conditions and nearby agricultural activity can change from year to year.
2. Ask Kewaunee County Public Health ((920) 388-7160) about current well-testing kit availability and any more recent countywide or localized testing data for the specific area you're considering.
3. If nitrate is a concern, treat any result near or above the 10 ppm nitrate-nitrogen health standard seriously -- this threshold exists specifically because of health risks to infants and pregnant women (methemoglobinemia, or "blue baby syndrome").
4. If a well tests contaminated, ask Kewaunee County Land & Water Conservation or the Wisconsin DNR directly about Well Compensation Grant Program eligibility before assuming the cost of replacement or treatment falls entirely on you.
5. For a new well on raw land, ask your well driller directly about the depth and specific geology at the site -- a well drilled below the shallow, fractured karst zone into a deeper, better-protected aquifer may carry meaningfully lower contamination risk than a shallow well in the same area, though this is a site-specific engineering question rather than something to assume either way.
6. If the parcel is near an existing dairy or livestock operation, see our companion livestock-feedlots page for how Wisconsin's CAFO permitting process (including groundwater monitoring conditions established by a case that originated in this county) may already apply to that specific operation.