WISCONSIN — In at least four Wisconsin municipalities, costs for private well replacements as a result of nitrate pollution exceed $116 million, according to a new report from the Alliance for the Great Lakes and Clean Wisconsin.

And that’s just a small fraction of the cost.

The “Nitrates on Tap” report looks at the millions of dollars in financial burdens that Wisconsin communities could face over nitrate contamination in drinking water, particularly in areas that are rural or have geology that allows nitrate to move through to groundwater more easily.

It also draws attention to the health crisis the harmful chemical is leading to, having been linked to cancer, pregnancy complications and more. It’s Wisconsin’s most “widespread” groundwater contaminant, as it continues to increase statewide.

So where are nitrates coming from?

Over 90% of the nitrate pollution has been linked to agriculture. Excessive manure and synthetic fertilizer are the main culprits, according to the report. Environmental leaders said in 2022, an estimated excess of more than 16 million pounds of fertilizer was applied to crops.

Study leaders called this out as contributing to the problem.

People who are affected often have to pay the cost themselves. At least one-third of Wisconsin families rely on private wells, where these contaminations are more likely, according to the study. If that well becomes contaminated, it’s not cheap. Costs can reach up to $20,000 for well replacement, which the report says isn’t a long-term solution to the problem.

Municipalities are also footing the bill, with Chippewa Falls, Plover, Janesville and Trempealeau — the four municipalities studied — paying over $45 million in nitrate mitigation. When municipalities have to pay these costs, public water systems are often left with no choice but to increase water rates, which trickles down to ratepayers.

Even farmers foot a bill when they over-apply nitrate. The study finds that growers spend about $8 to $11 million on excess application.

“Wisconsin communities are living with the health impacts and costs of nitrate contamination – costs that are largely borne by ratepayers and homeowners,” said Angela Blatt, senior agriculture policy manager for the Alliance for the Great Lakes. “We can’t just continue to dig our way out of the problem with groundwater wells. This report is a call to action for comprehensive changes in policy and practices that are necessary in Wisconsin – as well as other areas throughout the Great Lakes Basin – to protect our drinking water and stop the pollution at its source.”

While a program does exist to help homeowners, the Alliance for the Great Lakes said it has “restrictions that severely limit access for families” that are impacted. It also calls it a “stopgap,” saying it doesn’t address the root cause.

“Without stronger upstream controls on nitrate pollution, more families will face the high cost and growing scarcity of access to safe drinking water,” the report says.

The report calls for legislative and regulatory action to address the issue, particularly a more permanent solution.

Specifically, it recommends expanding eligibility and funding for the existing Private Well Compensation Program. The grants in that program currently cover up to 75% of eligible replacement costs and is capped at $12,000.

It also said leaders should obtain financial data from public water systems on costs to remedy nitrate contamination.

Long-term it suggested outdated groundwater public health standards need to be revised, as well as manure application rules in high-contamination areas.

“Nitrates are Wisconsin’s most widespread drinking water contaminant, with health risks even at low levels. The costs of treating our drinking water will only continue to rise, so we need to tackle this challenge at its source,” said Sara Walling, water and agriculture program director for Clean Wisconsin.

Read the full report and recommendations below: