Quarterly Monitoring

In March 2019, the Michigan Department of Environment, Great Lakes, and Energy (EGLE) began quarterly sampling of Public Water Supplies sampled during Phase I which had Total Tested PFAS levels of at least 10 ppt but did not exceed the USEPA LHA (70 ppt PFOS+PFOA).  This sampling will be done for one year (four quarters) and will help determine if there are seasonal changes in PFAS levels for these 61 supplies, to help prioritize and direct next steps.

Two systems which had Total Tested PFAS levels of at least 10 ppt but did not exceed the USEPA LHA (70 ppt PFOS+PFOA) use surface water as a source (Ann Arbor and Sims-Whitney Utilities Authority), and will be sampled as part of the Monthly PFAS Monitoring Program for Michigan’s Surface Water Supplies, including the Great Lakes.

View the map of the 2019 Quarterly Monitoring Program (pdf).

Sampling results will be provided on this page, once they are available. 

Other PFAS testing initiatives for drinking water:

• Phase I of the Statewide PFAS Sampling Survey
• Phase II of the Statewide PFAS Sampling Survey
• Monthly PFAS Monitoring Program for Michigan’s Surface Water Supplies, including the Great Lakes

Understanding the Sample Results

Definitions of the information provided in the sampling results tables:

• Population Served: The number of individuals served by the water supply.
• Quarter Sample was Taken: The quarter of the year the sample was taken. There are four quarters: Q1, Q2, Q3, and Q4.
• Sample Date: The date samples were taken at the water supply.
• Sample Number: The identification number that corresponds to the sample taken.
• Raw Water or Treated Drinking Water: The location where the water sample was collected. If the table shows “Raw Water” the sample was taken directly from the well or water source. If the table shows “Treated Drinking Water” the sample was taken after the water passed through treatment system(s) the water supply has in place.
• PFOA + PFOS (ppt): The amount of PFOA and PFOS added together.
  • If the results listed is “ND” the lab did not detect, or find, that PFAS was in the water sample.
• Total Tested PFAS (ppt): The amount of all PFAS chemicals that were tested added together.
  • If the results listed is “ND” the lab did not detect, or find, that PFAS was in the water sample.
• Method: The laboratory method used for analyzing the samples. For more information, please visit the Frequently Asked Questions.

*Results are provided in parts per trillion. A part per trillion (ppt) is the equivalent of 1 drop of water in 20 Olympic-size swimming pools

The table below shows testing results from the statewide sampling initiative for Michigan public water supplies. Additional results from the testing will be added as they become available.

The Public Water Supplies dataset is available for download on the data.Michigan.gov open data portal.