A day after the city beaches reopened, an increase of cyanobacteria blooms on Tuesday led officials to close three of them again.
City alerts notified Burlington residents of the closure of North, Texaco and Leddy beaches around 2 p.m.
All of the city beaches were closed Sunday afternoon for about 24 hours due to the seasonal blooms that can be toxic to humans and pets.
Parks, Recreation and Waterfront staff conduct a visual check for the blue-green scum on water bodies to close and reopen beaches and collect water samples to test for the presence of cyanotoxin which can be harmful to humans and animals, according to Erin Moreau, Burlington’s waterfront superintendent and harbormaster.
If they spot cyanobacteria via two visual tests, beach staff immediately start to clear the affected beach and post closed signs. The beach manager then notifies city and state health staff of the bloom and the closures are announced via email or text. Once a bloom is detected, staff keep monitoring it throughout the day, according to information posted on the parks website.
Cyanobacteria blooms are a long-term challenge on the lake. They occur naturally in freshwater, grow well when there are high amounts of nutrients like phosphorus and nitrogen, and can multiply quickly during the warmer months. The drop in evening temperatures and cooler weather often helps clear them up.
City beaches have seen three closures due to cyanobacteria this summer. The timing is similar to last year’s, when the city recorded blooms on July 12, 15, 20 and 22.
Residents may sign up on VT-Alert to receive alerts about beach closures.
— Auditi Guha
