Foam

Lake Foam Explained

What is lake foam?

Foam along lakeshores is usually a natural phenomenon caused by organic matter in the water. When plants, algae, or other organisms like fish or mussels die and break down, they release surfactants—compounds that reduce the water’s surface tension. Wind, waves, and currents mix air into the surface, creating bubbles that form foam. Foam often appears in long lines down the lake and collects along windward shores, coves, or eddies. This is a result of langmuir circulation.

Foam and Harmful Algal Blooms (HABs)

Some foam, especially during cyanobacteria (blue-green algae) blooms, can contain additional substances. Local researchers Rick Smith and Stella Woodard of Global Aquatic Research LLC (GAR) have found that foam produced during HABs can trap human-made pollutants, including:

• PFAS (“forever chemicals”)
• PCBs
• Heavy metals
• Organic toxins

Foam can form mid-lake, drift to shore, and linger for days, collecting more contaminants along the way. While algal cells get caught in the foam, the pollutants are the main concern, particularly PFAS, which persist indefinitely in the environment.

Finger Lakes Foam Research

GAR is expanding their research to several Finger Lakes (Keuka, Owasco, Seneca, Skaneateles) in collaboration with the Canandaigua Lake Watershed Association, Binghamton University, the NYS Water Resources Institute, and the NYS Department of Environmental Conservation. Volunteers are encouraged to report lake foam to help the team track when and where it occurs.

Read more about foam:

• ​Why is PFAS-enriched foam forming on some of the cleanest lakes in the country? | Binghamton News
• ​OUTDOORS: Why harmful algal blooms in the Finger Lakes are so challenging to mitigate | Sports | fltimes.com
• Researchers find foam, algae connection on Canandaigua Lake.  Democrat and Chronicle
• CLWA Receives Grant for PFAs Research – CLWA

Report Foam Sightings

GAR Finger Lakes Foam Tool