A secchi disk in blue-green algae.

LCC Blue-Green Algae Monitoring Program

A blue-green algae monitor taking a sample at North Beach. Photo by Lori Fisher

LCC initiated a blue-green algae monitoring program on Lake Champlain in 2004. We annually train and enlist citizen volunteers to observe and report on water conditions. Our award-winning program provides critical data on where and when blooms are happening. The information we gather is used by public health officials to assess whether the water is safe for swimming. 

We are monitoring blue-green algae, also called cyanobacteria, because blooms sometimes produce toxins that are harmful to people and pets. Volunteers are trained to avoid personal exposure. The point of the monitoring program is to raise awareness of the issue, build a database of information on the bloom frequency and be sure that any potential health hazards are recognized and avoided by all people. Visit the Vermont Department of Health's website for more blue-green algae facts.

We revamped the program in 2012 to involve more people and cover more territory. Volunteer monitors commit to going out once per week from mid-June through Labor Day. Observations are submitted via an online form and used to update the Lake Champlain Blue-Green Algae Tracking map. Repeatedly visiting the same site helps us know of not just the presence of blooms, but also their absence. LCC provides training in detecting blooms and distinguishing them from other floating phenomena. If you are interested in being a volunteer monitor or supporting this program, please contact us at (802) 658-1414 or lcc@ lakechamplaincommittee.org.

Stay Informed

The Vermont Department of Health has the latest updates on Lake Champlain algae conditions. Helpful locations on their website include the Lake Champlain Blue-Green Algae Tracking map and Guidance for Vermont Communities on the health affects of blue-green algae. To help people distinguish blue-green algae from other floating phenomena in the lake, the Lake Champlain Committee has prepared a pamphlet recognizing blue-green algae in Lake Champlain (pdf).

Background on Blue-Green Algae

Photo by Jessica Rossi.

Blue-green algae (cyanobacteria) naturally occur in lakes and have existed on earth for millions of years. Under the right conditions they form large accumulations referred to as blooms. Some types produce toxins which release into the water when algae die and break down. Algae toxins can present a potential hazard to people and their pets. However, not all algae produce toxins, and even those species that can produce toxins do not do so in all instances. You cannot tell by looking at a bloom whether or not toxins are present. Specialized tests are required to tell whether a particular bloom actually contains toxins.

What do blue-green algae blooms look like?

As a bloom develops you may notice fuzzy green pinhead size balls in the water. The actual bloom often looks like thick pea soup. You may see patches of turquoise blue as cells break down and release their pigments.

What are the health concerns with blue-green algae?

Compounds produced by the algae can trigger skin irritations and gastro-intestinal illness. Toxins in aerosols may cause itching and irritation of eyes, nose, or throat. Some species produce toxins that affect the liver, while other species’ compounds affect the nervous system. Blue-green algae toxins are also suspected carcinogens. Children and dogs are most vulnerable for a number of reasons: they are less particular about what they eat or drink or where they swim; they are smaller; and they are more likely to ingest water. Dogs can receive a larger dose of toxins when they swim in a bloom then lick their fur. The deaths of two dogs during the summers of 1999 and 2000 were attributed to blue-green algae poisoning from Lake Champlain water.

Where are blooms most likely to occur on Lake Champlain?

Blue-green blooms tend to be more prevalent in warm, shallow waters such as Missisquoi Bay. Deep, cold water locations with fewer nutrients, such as the Main Lake are less likely to support blooms. However, with warmer water temperatures associated with climate change and extensive nutrient loading from frequent storms and flooding, blooms are appearing in a broader area of the lake. Blooms are likely to occur during extended periods of calm sunny days. Wind and waves may cause them to accumulate along shorelines or in protected areas. Shifts in wind direction can move a bloom from one location to another. Cool rainy weather may disrupt a bloom.

What should I do if I see a bloom?

  • Report it to the Lake Champlain Committee (LCC) using our online form.
  • Avoid contact with the water in the area of the bloom. Blooms are often localized and you can recreate elsewhere in the lake.
  • Keep children and pets out of the water.
  • Do not drink untreated lake water. If you suspect a bloom near your intake, don’t drink, cook or shower with the water. Boiling water doesn’t destroy the toxins.
  • See a doctor if someone gets ill after exposure to an algae bloom and report algae-related illnesses to the health department.

What can we do to prevent blue-green algae blooms?

Nuisance algae blooms result from too much nutrient loading to the lake; preventing them requires a long term strategy. LCC works diligently to address root causes and advance efforts to reduce nutrient loading. We have championed bans on phosphorus in lawn fertilizer and laundry and dishwasher detergents and continue to advocate for stringent water protection regulations and enforcement, stormwater controls, and upgrading and maintaining wastewater treatment plants. At a personal level there are a number of steps you can take as described in our Lake Protection Pledge. These include using only phosphorus-free fertilizers, cleaning storm drains, preventing leaves and grass clippings from entering waterways, maintaining or planting native trees and shrubs around shorelines and streams to reduce erosion, properly maintaining your septic system, and many more.

Financial Support & Collaborative Partners

Photo by Carolyn Bates.

LCC's blue-green algae monitoring program is generously funded by LCC members, the Lake Champlain Basin Program, PC Construction, the Lintilhac Foundation, the South Lake Champlain Fund of the Vermont Community Foundation, and The Hickok and Boardman Network of Companies. Please contact LCC if you'd like to contribute to this program. Collaborating partners include New York and Vermont public health, environmental and recreational agencies and the Lake Champlain Basin Program.

LCC's Past and Ongoing Projects

  • Raised awareness of increase in blue-green algae blooms and pushed for research and monitoring to understand causes. 
  • Established and run a volunteer monitoring program. We train monitors around the lake to recognize blue-green algae and provide tools for them to report blooms. Information gathered is shared with the Departments of Environmental Conservation and Health to inform the public through about conditions.
  • Produced a brochure to help distinguish blue-green algae from other algae species and other floating phenomena in Lake Champlain.
  • Conducts weekly surveys of public access points around the lake during the summer and report on algae bloom conditions.
  • Advances policies, programs and regulations to reduce nutrient loading to Lake Champlain.

2014 Season in Review

Throughout the season LCC received algae monitor reports from 87 regularly reporting sites during the official monitoring season. The official monitoring season ran from June 15 to September 13; these are the weeks for which we received 45 or more observations from monitors. Regularly reporting sites were those from which we received reports in six or more separate weeks during that time frame. There were 939 reports from these sites during the official season. Of these , 95.5% indicated little or no blue-green algae present (category one), 2.6% indicated blue-green algae present at less than bloom levels (category two), and 1.9% indicated blue-green algae blooms in progress (category three). Reports of blooms were most likely in St. Albans and Missisquoi Bays. In fact, we received only one report of category three conditions that did not come from one of those two lake segments (Bulwagga Bay 8/12). In St. Albans Bay, 28.8% of regular reports were of category two or three conditions and in Missisquoi Bay 18.6%. Blooms first appeared in the last week of July and persisted through the end of the regular monitoring season. 

Algae monitor reports by lake section 2014. Explanation of categories: ‘little or no blue-green algae present’ (category 1), ‘little blue-green algae present but enjoyment of water not impaired (category 1d), ‘blue-green algae present – less than bloom levels – enjoyment of water slightly impaired’ (category 2), or ‘blue-green algae bloom in progress – enjoyment of water substantially impaired’ (category 3).