Cyanobacteria (Blue-Green Algae) Conditions

cyanobacteria bloom

Cyanobacteria, also known as blue-green algae, are naturally found in fresh water in the U.S. and in Lake Champlain and other Vermont waters. Some types of cyanobacteria can release natural toxins or poisons (called cyanotoxins) into the water, especially when they die and break down. People and pets should stay away from cyanobacteria blooms. Learn more about cyanobacteria

For information on other monitoring locations and reports from earlier this season, check the Cyanobacteria Tracker Map

Information on lake conditions is provided by a network of volunteers trained and coordinated by the Lake Champlain Committee and by scientists from the Vermont departments of Health and Environmental Conservation. Monitors submit weekly visual observations of water conditions from sites around Lake Champlain.

Weekly Summary of Cyanobacteria Conditions

Below you can find information on where monitors and the public have reported seeing cyanobacteria this week. Everyone, especially people in these areas, should watch for and avoid cyanobacteria.

“Low Alert” means that small amounts of cyanobacteria were observed. “High Alert” means that large amounts of cyanobacteria were observed with dense scums or highly colored water.

Be aware of changing conditions and keep out of the water if you think cyanobacteria might be present.

Cyanobacteria Reports Received This Week - Updated September 13, 2019

Location of Report Waterbody Town Alert Level Date
Black Bridge Lake Champlain St. Albans Town Low Alert 9/10/2019
Carmi DEC01- Central Open Water Lake Carmi Franklin Low Alert 9/12/2019
Carmi DEC02- Southern Open Water Lake Carmi Franklin Low Alert 9/12/2019
Carmi DEC03- Northeastern Open Water Lake Carmi Franklin High Alert 9/12/2019
Dunham Bay Lake Champlain North Hero Low Alert 9/12/2019
Fee Fee Point Lake Champlain North Hero Low Alert 9/9/2019
Graveyard Point Lake Champlain North Hero Low Alert
Low Alert
Low Alert
Highgate Springs Lake Champlain Highgate Low Alert 9/10/2019
Lake Carmi State Park Lake Carmi Franklin High Alert 9/10/2019
Lake Carmi, North Beach Lake Carmi Franklin High Alert 9/10/2019
LTM 50 Lake Champlain Swanton Low Alert 9/10/2019
LTM 51 Lake Champlain Philipsburg, QC Low Alert 9/10/2019
Melville Landing Lake Champlain Georgia High Alert 9/9/2019
Phillipsburg, QC Lake Champlain St. Armand, QC High Alert 9/10/2019
Pt. Au Roche State Park- Deep Bay Lake Champlain Beekmantown, NY Low Alert 9/11/2019
South Alburgh - Squires Bay Lake Champlain Alburgh High Alert 9/10/2019

identifying cyanobacteria

It's important to know what cyanobacteria look like and to use your best judgment when thinking about swimming or doing other activities in the water. See photos of what cyanobacteria look like and what are not cyanobacteria.

Watch a video to help you identify cyanobacteria

Weekly drinking water test results

All 22 public drinking water suppliers on Lake Champlain submit samples for cyanobacteria toxin analysis. Drinking water test results are updated weekly by the Vermont Department of Environmental Conservation.

See the drinking water test results

Partners in Monitoring Vermont’s Waters

  • Lake Champlain Basin Program – funds cyanobacteria monitoring in the Lake Champlain Basin.
  • Lake Champlain Committee (LCC) – since 2003, coordinates and trains a group of citizen volunteers to monitor shoreline sites on Lake Champlain in Vermont, New York, and Quebec. You can reach out to LCC if you are interested in becoming a volunteer monitor.
  • Vermont Department of Environmental Conservation – monitors long-term water quality at dozens of off-shore stations on Lake Champlain and recruits and trains volunteers on many other Vermont lakes.
  • Vermont State Parks – monitors conditions at park swim areas.

For more information or to report a bloom:

Email with photos of the suspected bloom. If possible, include a detailed description of the bloom's location, or mark the bloom location using an image from an online mapping application such as Google, Bing or Yahoo Maps.