Almost 97% of Wisconsin’s municipal water utilities met safe drinking water standards last year, although more than one out of 10 failed to notify customers of lapses in monitoring, treatment or other violations, according to a report from the state Department of Natural Resources.
The DNR reported a total of 449 violations of safe water standards at 101 of more than 11,500 systems in 2018 for contaminants such as bacteria, nitrate, arsenic and radionuclides.
Of the systems with violations, more than half were among the 9,590 licensed campgrounds, parks, motels, restaurants, churches or other businesses that serve the public but are not considered primary sources of drinking water.
Just over 3% of the 610 municipal water systems exceeded contamination limits, and more than half of those violations were radium or other radionuclides.
Cambria, DeForest South, Evansville, Marshall, Pewaukee, Tomah and Waukesha were among the municipal systems with radionuclide contamination. Oak Creek and Superior had high levels of trihalomethanes, a group of compounds formed by the reaction of chlorine with organic material in the water.
“The absolute vast majority of them are in compliance, which is really good news,” said Adam DeWeese, section chief of the DNR Public Water Supply Section. “Some of these contaminants are not the fault of public water systems. They’re just in the water. It’s not because they did anything wrong.”
But contaminants like lead, arsenic and nitrate continue to pose challenges, according to the DNR.
While the state’s largest public water systems have taken steps to protect customers from lead and copper, lead service lines are still common in many communities. Nitrate, the most widespread contaminant in Wisconsin’s drinking water, has been linked to diseases like cancer and is especially dangerous for infants.
Municipal water works must also contend with the high costs of replacing aging pipes.
The DNR reported violations at about 5% of systems for failure to properly test the water supply. And 9% of all systems — including 13% of municipal utilities — failed to promptly notify customers of contamination or problems with monitoring and treatment.
DeWeese said those violations typically involve missed deadlines.
In addition, some 279 non-community systems — such as restaurants, bars and campgrounds — were allowed to operate with nitrate levels above the limit of 10 micrograms per liter, as long as they notify the public, ensure the water is not consumed by pregnant women or infants and provide an alternate source of water.
DeWeese said the DNR is considering whether to continue that allowance.
The report does not address PFAS, a group of hazardous but not-yet-regulated chemicals that have been found in wells serving Madison, La Crosse, Peshtigo and other communities.
Earlier this year, Gov. Tony Evers ordered the DNR to begin a 30-month process of establishing standards for the compounds, which have been used in firefighting foam, food packaging, non-stick cookware, water-resistant clothing, carpeting and other products, and have been shown to increase the risk of cancer and other ailments.
Monday’s report also does not address the condition of the private wells that provide drinking water for about 1.7 million Wisconsin residents.
The Department of Health Services estimates at least 1 in 10 Wisconsin wells has high levels of nitrate, which is considered hazardous, especially for pregnant women and infants. A recent study found 42% of wells in southwestern Wisconsin exceeded federal standards for bacteria or nitrate.
Scott Laeser, water program director for Clean Wisconsin, said the report is generally good news, but the state needs to continue efforts to address lead pipes, PFAS and groundwater contamination in general.
“We need to translate some of this work on protecting citizens in municipalities to protecting folks who rely on private wells,” Laeser said.