Organic compounds from decomposing plants in the lake/river reach the water's surface, where wind and wave action push them to the shore. The concentration, or build up, of the organic compounds changes the physical nature of the water, making it easier for foam to form. Turbulence and wave action at the beach pushes air into the water with organic compounds, which forms the bubbles in foam. Currents and boats also mix air with the organic compounds in the water to produce naturally occurring foam. Foam can appear year-round on lakes and streams as long as there is open water. Scientists are still studying why and how PFAS foam appears in some lakes and streams and not in others.

Foam:

• Can be white, off-white or brown.
• Is usually lightweight.
• May have an earthy or fishy smell.
• Often piles up in bays, eddies, dams and other river barriers.
• Can be sticky.
• May blow inland.
• May contain harmful bacteria, algae or chemicals, such as PFAS. 

Foam can have much higher concentrations of PFAS than the waterbody it is found in. Foam can also contain harmful bacteria. Swallowing any foam could be a risk to your health. MDHHS recommends everyone avoid all foam on lakes, rivers and other surface water.

As a precaution, MDHHS in partnership with local health departments issues PFAS foam recommendations and/or advisories on lakes and streams impacted by PFAS contamination.  Foam recommendations and/or advisories have been issued by MDHHS and implemented by local health departments for the following waterbodies:

• Van Etten Lake, Oscoda. September 1, 2017
• Lake Margrethe, Grayling, June 5, 2018
• Rogue River, Rockford, June 5, 2018
• Thornapple River, Grand Rapids, June 29, 2018
• Huron River, Southeast Michigan, September 18, 2018

The amount of PFAS in lake and river water and in foam matters in determining if a health concern exists. MDHHS will continue to evaluate surface water and foam data when it becomes available and will issue further recommendations if necessary.

Learn more about known PFAS sites

If you suspect PFAS foam has formed on a lake or river, report it to EGLE by completing a “Spill/Incident/Pollution” form in the EGLE MiEnviro Portal.  You will be able to submit photos of the foam if you have them. 

Information collected through this form will be used to understand foam occurrence, help EGLE look for potential sources of contamination in the area, and help EGLE plan annual lake and stream monitoring.

Or, instead of filling out the form, you may call the 24-hour Pollution Emergency Alert (PEAS) hotline at 800-292-4706 to report the foam. Helpful information to be provide when completing the complaint form, or if you call the PEAS line, include:

• Your contact information (name, address, phone number).
• Location information - Where exactly the foam is located:
• e.g., Lake Margrethe at Little Bear Point
• Nearest address and or latitude/longitude coordinates if known
• Color of foam (bright white/off white/other).
• Consistency of foam. Is it light and fluffy like shaving cream or watered down with organic matter?
• How much foam is present, length by width by thickness? (We understand this is an estimate/best guess.)
• If it is a floating mass of foam, which direction is it moving?
• What time did you first observe the foam, and is it still present?
• Have you seen the foam in previous years?
• Optional but helpful: wind speed, wind direction, air temperature.
• Optional but helpful: did/can you take a picture of the foam?

PFAS contaminated foam was first discovered on Van Etten Lake in July 2017 when a group of high school students participating in the Science, Technology, Engineering and Math (STEM) summer program hosted by Michigan State University and Dow of Midland, encountered foam as they prepared to sample Van Etten Lake surface water for PFAS. Noting the amount of foam and its unusual characteristics (stiffer and whiter than foams that naturally occur on lakes), they decided--with permission from their sponsors--to sample the foam. The foams were contaminated with several PFAS compounds, but most notably with PFOS.

Between 2018 and early 2020 EGLE sampled PFAS foam at Van Etten Lake and Cedar Lake in Oscoda near the former Wurtsmith Air Force Base and on Lake Margrethe in Grayling near Camp Grayling. Foam was also seen and tested at several other locations.  The results of this sampling are included in the Surface Water and Foam Results Summary Spreadsheet. 

Note that there are no standards for PFAS in foam, so no regulatory actions can be taken due to these results.  All results are shared with MDHHS so that they can evaluate the data to determine if a foam advisory is needed.

View the Surface Water and Foam Results

In 2019 and 2020, the only foam sampling that was conducted was done as a part of an AECOM study intended to do two things: 

• Determine the best way to sample foam. As of early 2020, two methods were being used to sample foam:  either a modified pool skimmer or by hand (using powderless nitrile gloves). 
• Determine how foam forms. As part of this effort, foam was collected at six locations around the state. The samples were analyzed to determine if there were PFAS chemicals or bacteria in the foam, and whether there were certain types of surfactants present that might influence the formation of foam. The results of the study and foam sampling collected as part of this effort is included in the Surface Water Foam Study Report.

At this time, Michigan is actively tracking PFAS foam appearances on lakes and streams, using foam sightings to guide future surface water and fish contaminant monitoring for PFAS and assist in finding sources of PFAS.  EGLE uses existing regulatory programs to address discharges from identified sources that are impacting lakes and streams and may be contributing to the foam. 

EGLE has also used drones to find groundwater seeps to help understand where the PFAS contaminated foam may be coming from. 

Learn more about EGLE's use of drones