Clinton River/Lake St. Clair


The Clinton River drains portions of four counties in southeast Michigan. The Clinton River Watershed drains 760 square miles and flows 83 miles from its headwaters to Lake St. Clair. Lake St. Clair connects Lake Huron to its north with Lake Erie to its south. The Michigan Department of Environmental Quality (MDEQ) began sampling intensively in the Clinton River due to 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 Clinton River / Lake St. Clair Watershed.          

  • PFOS and PFOA were detected in the two surface water samples collected on 8/31/17, from the Clinton River near the city of Mt. Clemens and along the Lake St. Clair shoreline just north of the Selfridge Air National Guard Base in Harrison Charter Township.These samples were collected as part of a targeted monitoring project designed to identify surface waters that could potentially have elevated levels of PFAS.
  • As a follow-up to the initial findings, fish and surface water samples were collected in November 2017.Surface water samples in Lake St. Clair and the Clinton River contained PFOS above the applicable surface water criteria. The maximum value was 610 ppt.One elevated data point in the Clinton River is upstream of Selfridge ANGB.
  • DHHS has issued fish advisories for bluegill and sunfish as a result of PFOS concentrations.
  • Downstream drinking water systems in the Detroit River and lower Lake St. Clair were sampled in November 2017.All results were non-detect, with reporting limits ranging from 1.93 to 2.43 ppt.These samples are not included in the table because they are not immediately in the area of the site.
  • Effluent from area waste water treatment plants has been sampled for PFOS and PFOA.The results ranged from 5.6 to 14 ppt.
  • AECOM has conducted sampling of the soil, groundwater, and surface water at Selfridge under contract with the National Guard Bureau.Validated results from this sampling are expected in late August/early September 2018.
  • Validated outfall data has been received from Selfridge.Elevated levels of both PFOS and PFOA were detected in the outfalls.The highest concentrations are 2,400 ppt and 290 ppt, respectively.A Violation Notice for exceedances of water quality standards was issued on 7/19/18. Response due 9/21/18.
  • AECOM sampled the raw and finished drinking water from the Ira Township, New Baltimore, and Mount Clemens drinking water plants in January 2018.While PFAS were detected, the combined levels of PFOS and PFOA were well below the LHA of 70 ppt.These samples are included in the table below.
  • Another round of surface water samples were collected in the Clinton River in February 2018.PFOS and PFOA concentrations were detected above the reporting limits. One sample exceeded the applicable surface water criteria for PFOS at 43 ppt.
  • The vast majority of residents in the vicinity are serviced by municipal water supplies, but a small number of private wells are still in use.AECOM sampled four residential wells near Selfridge and a Type II water supplier near Lake St. Clair on 5/2/18.All samples were non-detect for PFOS and PFOA.Another round of residential well sampling is currently being scheduled.
  • AFFF spill reported at Selfridge on 6/7/18.Foam was seen on the canal between the base and Lake St. Clair.Emergency response was enacted by the United States Coast Guard.DEQ collected samples and assisted in oversight of response activities.PFOS in high concentrations seen in foam and water on-base.A temporary carbon treatment system was put in place to treat discharge water.Concentrations are now at or near pre-spill levels.No impact to drinking water (Mt. Clemens WTP sample was non-detect).
  • Letter sent to Axalta on 7/20/18 requesting PFAS sampling. Axalta facility is upstream of elevated PFAS levels in Clinton River tributary.Axalta has agreed to the sampling request.Results of the testing are expected in October 2018.
  • Results from the public water supply sampling is included in the table below.

# Public Water
Supply Samples

# Public Water Supply
Results Received

# Non-Detect

#ND – 70 ppt

#> 70 ppt

Highest Public Water
Supply value in ppt







Clinton River and Lake St. Clair Community Briefing on PFAS - November 8, 2018