Source Water Protection Web Map Viewer
The Source Water Protection Unit evaluates where drinking water comes from and how vulnerable drinking water sources are to outside contamination. This information is used to define management areas for drinking water protection.
Our interactive web map viewer features several types of source water protection areas. In this map, you can see where communities source their drinking water and identify whether or not you are in a protection area. You can also learn how vulnerable a drinking water source is to outside contamination.
How to use the web map viewer
In the web map, you can:
- Navigate to an area by using the search bar, zooming in and out, moving the map, or finding your location;
- Turn map layers on or off and change their transparency;
- View the legend;
- Click on an area to view more information about it;
- Measure area or distance;
- Change the basemap; and
- Print a map.
Information in the web map viewer
Wellhead Protection Areas (WHPAs) – areas surrounding public water supply wells that contribute groundwater to the well. In these areas, contamination on the land surface or in water can affect the drinking water supply.
Drinking Water Supply Management Areas (DWSMAs) - areas containing the wellhead protection area but outlined by clear boundaries, like roads or property lines. The DWSMA is managed in a wellhead protection plan, usually by a city.
DWSMA vulnerability – how likely it is that contamination in the DWSMA can reach the public water supply intake.
Emergency Response Areas (ERAs) – areas surrounding public water supply wells where water has a one-year travel time to the well. ERAs are used to prioritize and manage potential contamination sources in the DWSMA.
Geospatial data files for these and other source water protection areas are available for download on the MDH website.