Occurrence in Wisconsin

Public Well Sampling Map - (94 Kb)
This map displays public well samples in the state with a concentration of arsenic greater than 10 parts per billion (ppb). The data is from the DNR Public Water Supply database covering from 1973 - 2000.

Private Well Sampling Map - (103 Kb)
This map displays private well samples in the state with a concentration of arsenic greater than 10 ppb. The data is from the DNR Private Water Supply database covering from 1988 - 2000.

Arsenic Advisory Area Map - (211 Kb)
This map depicts an area five miles either side of the sub-crop of the St Peter Sandstone. Since the St. Peter Sandstone is one of the primary sulfide minerals bearing zones (and thus arsenic bearing) and is shallow, lying just below the glacial sediments, the area has a higher potential for the development of water quality problems. Other areas, outside of that shown on this map, may also have arsenic depending on local conditions, well construction, use and maintenance. [Smaller printable version - (150Kb)]

Tables summarizing sampling from public wells and private well town-based sampling for arsenic.

  • Public Well Sampling (Excel spreadsheet - 19 Kb)
    In 2000 the DNR sponsored a special sampling program to investigate arsenic occurrence in public wells. The sampling was designed to gather comparable data from all public wells and to maximize arsenic occurrence. For municipal wells (MC) a time was calculated for each well that was equal to 0.8 well volumes divided by the pumping rate. For other than municipal (OC) and non-transient non-community (NN) wells average times of six and seven minutes were used. The results are presented for both the wells and systems.


  • Town Based Sampling (Excel spreadsheet - 26 Kb)
    The DNR, along with Department of Health and Family Services, Department of Commerce and Local Health Departments has been sponsoring sampling of private wells by civil towns in Outagamie and Winnebago Counties. The results are presented by town for the number of samples and percentage of samples above a given arsenic concentration level.
Links to DNR Well and Water Sample Databases:


Last Revised: Monday October 11 2004