University of Wisconsin - Extension

Fall is a good time for homeowners to check the condition of their drinking water wells. Diligent well maintenance now can help ensure a safe, year-round supply of well water.

Nearly all of Wisconsin's rural residents use groundwater to supply their drinking water and farmstead needs. There are approximately 750,000 private wells in Wisconsin, according to the Department of Natural Resources.

In the fall, insects, mice and even snakes are looking for winter homes. Wells offer a relatively warm and sheltered spot for them to live if openings in the well cap are not properly sealed. Contamination of the well with bacteria may result. Installing a vermin-proof cap will prevent insects from entering drilled wells. Sealing openings in an older cap, while maintaining an air vent, is another possible solution.

Keeping the well area clean and accessible is also important. Keep leaf piles, wood piles and pets away from the well.

"Good maintenance also includes testing the water every year for bacteria, nitrate and other contaminants of special concern in your area and keeping pollutants as far away as possible," explains Chris Mechenich, University of Wisconsin-Extension water quality specialist. "A qualified well driller or pump installer can also help check the well condition and mechanics."

Homeowners can perform a pollution risk assessment of their well water through HOME-A-SYST, a national program originated by the University of Wisconsin-Madison/Extension to show people how to protect groundwater and their own well water. The program contains worksheets to help homeowners assess and reduce the risk of well water contamination.

The following additional tips to keep well water safe are offered through HOME-A-SYST:

1. Make sure well casings are properly sealed and are not cracked or perforated.

2. Install water-tight seals at the bases of hand pumps.

3. Make sure well casings extend far enough above ground so that surface water cannot enter the well.

4. Maintain safe distances between potential pollution sources and wells.

5. Consider moving such activities as pesticide mixing, tank rinsing or gasoline storage further from your well.

For more information about HOME-A-SYST, contact your County Extension office.