I am purchasing a new home, can the viewer locate water quality results for a particular well or property?
No.Well data is not publicly available to a specific property. Anytime you invest in a new home or property with a private well we strongly encourage you to have it inspected by a certified well inspector and have it sampled for some basic water quality concerns at that time.
A well can be significant to the overall value of a rural property. Knowing what condition the well is in and having a current water quality test can be important when finalizing the sale of a rural property with a well. Water quality can also change over time and its always best to get a current evaluation of water quality.
Sampling the well prior to purchasing the property is the only way to know for sure the current water quality.
The viewer can be useful in providing some information on what water quality is like in the area or what additional parameters might be worth testing for. The value of the water quality viewer is in the amount of data displayed. It does a good job of showing areas where water quality has been degraded or is more likely to exceed certain drinking water standards. It relies on the law of averages and requires large numbers of samples in order to characterize water quality for a county or town. The smaller the number of samples the less representative the information will be of water quality in an area.
The viewer is not a replacement for a water test.
Is groundwater quality getting better or worse?
The viewer is good at identifying areas where water quality issues exist. It is not designed to look at trends in water quality over time.
Answering whether water quality is getting better or worse requires baseline data as a starting point and regular monitoring of wells into the future. This viewer is a good start for communities to view baseline data and identify areas where more data is needed. It can also help communities focus future water quality testing efforts in areas where problems exist.
If the viewer is successful in encouraging private well owners to perform routine well water testing, then in the future we will have a better chance of answering whether groundwater quality is getting better or worse.
Information on trends in nitrate-nitrogen in Wisconsin's public water systems can be found here:
Nitrate in Wisconsin's Public Water Systems
A few counties have initiated projects to investigate well water quality trends in their communities: Community Trend Monitoring Projects
Other historical statewide groundwater quality inventories:
Wisconsin Groundwater Quality - DATCP, 2023
Wisconsin Groundwater Quality - DATCP, 2017
Wisconsin Groundwater Quality - DATCP, 2008
Wisconsin Groundwater Quality - DATCP, 2002