Blue-Green Algae Status Map Tracks Blooms on Lake Champlain


DATE: July 20, 2005

Contact: Communication Office

BURLINGTON – Scientists and health officials who routinely test the waters of Lake Champlain for signs of blue-green algae would like to see a few more people plunge - worry free - into the water this summer.

Swimmers and boaters can access weekly information about blue-green algae conditions around the lake from a status map that clearly details the location and severity of blooms. Recreational alert levels of generally safe (go ahead and plunge), low alert (caution is advised) and high alert (hazardous) will be posted to stem a growing tide of questions and concerns about the pea-soup colored scum.

“We were not aware of the potential problems with blue-green algae until the late 1990s,” said Dr. Mary Watzin, director of the University of Vermont Rubenstein Ecosystem Science Laboratory. “But as people have become more aware of the blooms and the health risks, we have seen a sharp increase in public concern and questions.”

Some kinds of blue-green algae produce natural toxins or poisons that can be harmful if swallowed, and skin contact can cause rash or irritation. Children and dogs are especially vulnerable because they are more likely to drink the water.

No human cases of illness related to blue-green algae in Lake Champlain have been documented, but during the summers of 1999 and 2000 two dogs died after drinking large amounts of water from a toxic blue-green algae bloom.

“The map isn’t designed to scare people or discourage them from enjoying the lake this summer,” said Bill Bress, state toxicologist for the Vermont Department of Health. “It’s a resource designed to provide timely information and alleviate concerns.”

Online information including the map, photographs of algae blooms, and facts about blue-green algae was created through a cooperative effort by the Health Department, the Vermont Department of Environmental Conservation and the University of Vermont Rubenstein Ecosystem Science Laboratory.

Testing for blue-green algae toxin in private swimming waters or drinking water systems fed by a lake or pond can be performed at the Health Department Laboratory. Water should be collected using kits which can be requested by calling the laboratory at 800-660-9997. The tests cost $20, payable upon submission of the samples to the lab. Samples will be tested on Tuesday and Thursday of each week and results mailed the following day.

To visit the status map go to:

The Health Department is encouraging lake users to report potential blue-green algae blooms. To report a bloom, call 1-800-439-8550 (VT only).