Whether it’s the kitchen faucet or a barn hydrant, most of us rely on the same underground water source. While people on municipal systems have their water tested for them, private well owners are responsible for testing their own wells. The Wisconsin Department of Health Services recommends testing your well every year for nitrates and bacteria, and at least every 5 years for arsenic and lead, but many private well owners don’t know when they last tested their water.
The good news is that Green County Public Health now has a certified water testing lab right here in Monroe. Green County Public Health Water Lab is certified by the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) and the Wisconsin Department of Natural Resources (DNR) to test water for coliform bacteria, E. coli, and nitrates. This expanded service strengthens the Green County Public Health’s commitment to safe drinking water and offers residents and local organizations a more convenient, accessible option for water testing.
Getting your water tested is simple. Residents can pick up water test kits directly from the Green County Public Health Office, no appointment needed. After collecting a sample, individuals should return it to the office within 24 hours of collection for accurate results. In addition to our new lab testing options, the UW-Stevens Point homeowner test kits and WellTAP kits will continue to be available at our office for Green County residents. Our new local lab makes testing faster and more convenient, without long drives or mailing delays. “Routine well water testing is important for protecting the health of our community,” said RoAnn Warden, Green
County Health Officer. “We are thrilled to offer this new service locally and make water testing more accessible for all Green County residents.”
Spring is a great time to test your well water, because well contamination problems can happen after the spring thaw. Groundwater contamination is a widespread issue in Wisconsin and can lead to both acute illness and long‑term health concerns. In 2025, 17% of private well tests in Green County showed nitrate levels exceeding the health standard of 10mg/L. While high nitrate levels can affect anyone, infants are particularly vulnerable and may develop “blue baby syndrome,” a condition that reduces the blood’s ability to carry oxygen. High Nitrates can also increase the risk of birth defects, thyroid disease, and colon cancer. Bacteria can also contaminate well water, especially if it is poorly constructed, located near sources of waste, or impacted by flooding. Drinking contaminated water can cause symptoms of stomach illness, such as diarrhea, nausea, vomiting, stomach cramps, and fever.
As spring approaches, Green County residents are encouraged to test their private wells and learn how to keep their drinking water safe. For more information about water testing services, visit our website gcpublichealth.org or contact Green County Public Health at 608‑328‑9390.
— Ellie Lombardo is the Public Health Educator for the Green County Public Health Department and can be reached at
elombardo@greencountywi.org or 608-328-9509.
