The Huron River drains portions of seven counties in southeast Michigan. The Huron River Watershed is more than 900 square miles and consists of hundreds of tributary creeks, lakes, and the Huron River proper. The Michigan Department of Environment, Great Lakes, and Energy (then the Michigan Department of Environmental Quality (MDEQ)) began sampling intensively on the Huron River due to the city of Ann Arbor detecting per- and polyfluoroalkyl substances (PFAS) in the Huron River, which is the main source of the city of Ann Arbor’s drinking water, and the discovery of perfluorooctanesulfonic acid (PFOS) in the river at levels over the Rule 57 water quality standard of 11 ppt PFOS. The following is a timeline of PFAS investigation activities in the Huron River Watershed.
Next Steps
- Continue to work with the city of Wixom and Tribar to control/reduce discharges to the WWTP with the goal of meeting the Rule 57 water quality standards in Norton Creek under the IPP PFAS Initiative.
- Evaluate known sources of environmental contamination, closed landfills, hazardous waste facilities, and facilities that discharge wastewater to the Huron River.
- EGLE will continue to sample fish from selected waterbodies in the Huron River watershed and provide results to MDHHS as available.
Investigation Timeline
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City of Ann Arbor: 2014 - 2018
- The city of Ann Arbor supplies water to city of Ann Arbor residents, as well as residents in Ann Arbor Township and Scio Township. The total population served is 127,855. The city of Ann Arbor gets 85 percent of its water from the Huron River via two water intakes in Barton Pond and 15 percent from multiple groundwater wells. Below is a timeline of PFAS-related activities:
- March 5, 2014 – The city of Ann Arbor sampled for PFAS compounds in drinking water, as required by the United States Environmental Protection Agency (USEPA) under Round 3 of the Unregulated Containment Monitoring Rule (UCMR3). PFOS was detected in the drinking water sample (main reservoir – treated water) at 43 parts per trillion (ppt). Review the city of Ann Arbor’s 2014 Water Quality Report.
- March and July 2016 – The city of Ann Arbor conducted water sampling for PFAS; they tested raw water sources as well as finished water. All but one of these upstream locations had detectable levels of PFAS and no obvious source was able to be pinpointed. The sample locations were:
- Main water reservoir (treated water) and the raw river intake (untreated water).
- Two raw water production wells (untreated groundwater).
- Surface water within the Huron River, Barton Pond, and Honey Creek (upstream of the intake; untreated surface water). See map of surface water results below.
- October 2016 - The city of Ann Arbor began collecting monthly PFAS samples from the raw river source and finished water. The results are provided to the MDEQ monthly. To date, all the results obtained are below the USEPA Lifetime Health Advisory of 70 ppt, either individually or combined.
View Entire Timeline
