Michigan well and pump records can reveal much about the geology of your home site

If you have a private drinking water well, your Water Well and Pump Record can help you understand what potential drinking water contaminants may exist in your area.

Many Michigan residents depend on groundwater as a source of clean, drinking water. In certain places in Michigan, bedrock is close to the surface. In these areas, drinking water is obtained by drilling into the bedrock to obtain water that is stored in the cracks and spaces within the bedrock. In other parts of the state, there are layers of soil of various thicknesses over the bedrock, called glacial drift. Drinking water in these areas comes from wells dug into those layers.

The geology of a site helps to determine whether water and contaminants are more likely to filter into the ground or move across it as storm water.

Well and Pump Record

Photo used with permission from MDEQ

Consider how two different sites can protect or harm groundwater and surface water:

  • A site that has a lot of clay at or near the surface- on one hand, clay at the surface can slow the downward movement of nutrients and contaminants, thereby protecting groundwater supplies. On the other hand, the relative impermeability of the clay can lead to stormwater runoff that can carry harmful materials directly into nearby surface water. Because clay can slow the downward movement of pollutants in water, it is ideal to construct a well that goes through a layer of clay.
  • A site that has a lot of sand at or near the surface- sandy soils tend to be well drained compared to clay soils. A spill that occurs on sandy soil has the potential to be carried downward into groundwater very quickly.

If you have a private drinking water well, you can learn more about the geology of your land by reading your well log. Well logs are available online (see below) or from your local health department and give a rough idea of the geology of a site. They indicate the type, thickness and depth of the layers the contractor drilled through to reach water. Water well drilling and pump installation contractors have been required to file logs for drinking water wells they have drilled in Michigan since 1967.

You can find Michigan well and pump records on several websites:

  • Wellogic
    Well-drilling contractors have submitted water well and pump records to this interactive website since 2000. Some older records were also imported from the former database, Wellkey. The Wellogic system is managed by the Michigan Department of Environmental Quality (MDEQ).
  • Scanned Well Logs
    This MDEQ site contains digital scans of paper well records submitted by water well drilling and pump installation contractors from 1999 and earlier. If you can’t find a well record in this system, MDEQ officials recommend contacting the local health department to see if they have a copy.
  • Water Well Viewer
    This site shows all of the water wells in Wellogic that have latitude and longitude coordinates on a map. The site was developed by the MDEQ and the Remote Sensing & Geographic Information Systems (GIS) Research and Outreach Services at Michigan State University.

For further information regarding the above websites, please email the Wllogic Help at wellogic@michigan.gov.

Private drinking water well owners should test their water at least once a year to ensure it is safe to drink. For more information on water testing, read the Michigan State University Extension article, “Protecting the water quality of your water well.”

Did you find this article useful?