The La Crosse County Health Department will collect water samples from private wells this month for water quality testing. Private well owners can drop their water samples off between 4 and 7 p.m. Tuesday, Aug. 20, at the Hazel Brown Leicht Memorial Library in West Salem.
The Environmental Protection Agency does not regulate private wells, so private well owners are responsible for their water.
The Wisconsin Department of Natural Resources encourages homeowners to test their private wells at least once a year for coliform bacteria contamination, the kind of bacteria found in animal digestive tracts and feces.
Coliform bacteria are used to assess the sanitary condition of the water supply. The DNR also recommends testing private wells whenever the color, taste or smell of the water changes.
La Crosse County offers bacterial testing, as well as tests for nitrates, arsenic and a metals panel, said county health educator Casey Mrozek.
Anyone who wants their well water tested can drop samples off at the county health department’s office, which is open from 8 a.m. to 4:30 p.m., Mrozek said. The library collection gives private well owners in more rural parts of the county another opportunity to bring water samples to department staff for testing.
Water testing bottles are available for pickup at the La Crosse County Health Department, West Salem Village Hall, Barre Town Hall, Bangor Village Hall and the West Salem library. The collection bottles come with instructions for how to take well water samples, Mrozek said.
Nitrates are considered Wisconsin’s most widespread groundwater contaminant, according to the state’s Groundwater Coordinating Council report to the Wisconsin legislature in 2018. Nitrates, present in plants, manure and fertilizers, enter the water supply as runoff from fields and septic systems. Exposure to nitrates decreases the oxygen-carrying capacity of red-blood cells, leading to a potentially fatal disease in infants known as blue baby syndrome.
About 10% of private well samples exceed federal drinking water standards for nitrates, and one-third of private well owners have never tested their water for nitrates, according to the council report.
In La Crosse County, about 30% of private wells exceeded federal standards for nitrates, according to a 2017 county survey of 540 private wells in the towns of Holland and Onalaska.
The federal drinking water standards for nitrate is 10 parts per million. Drinking water with arsenic levels of 10 parts per billion or higher are considered unsafe by the EPA.
Arsenic is an element found naturally in soil and bedrock. Arsenic poisoning from arsenic released into groundwater can damage blood vessels and nerves, cause anemia, and increase blood pressure and the risk of certain types of cancer. Low-level chronic exposure in children can also lead to decreased intelligence.
In La Crosse County, 3.8% to 7.2% of wells had water with arsenic levels considered unsafe by the EPA, according to the council report.
The county recommends that private well owners who haven’t tested for arsenic before get their water tested for arsenic, Mrozek said.
The laboratory test for arsenic costs $29, Mrozek said. Testing for a panel of 13 metals costs $96, and testing for bacteria and for nitrates costs $27 each.