BURLINGTON — As crowds have begun flocking to Burlington beaches amid coronavirus cabin fever and hot temperatures, cyanobacteria blooms have begun popping up again around Lake Champlain.
The potentially toxic blooms — which are caused by the combination of continued infusion of nutrient-rich runoff into the lake and warmer water temperatures — forced the closure of North Beach and Texaco Beach last week. The blooms have also been seen at swimming areas around the region.
“It’s again reflecting some of the unusual weather that we’re seeing here,” said Steve Smith, the director of animal care and facilities at ECHO, a science center and museum on the Burlington waterfront. “We are seeing a warmer lake and we’re seeing the water level is low, too.”
The blooms come after lake waters hit 77 degrees in June, the warmest ever recorded in the month. The water level is under 95 feet. The average level is 96.5 feet, according to the Lake Champlain Basin Program.
“That really can affect a whole ecosystem going forward throughout the growing season,” said Eric Howe, the director of the LCBP. “The earlier in the year that the lake begins to warm up, that kicks the growing period into gear.”
Blooms pop up earlier in the summer with hot temperatures and low water levels, Howe said.
“The lake hadn’t quite set up for blooms at that point — fortunately, because there were a lot of people out and about in the lake at that point,” he said. “I would say the blooms are appearing a little bit later than normal this year. It could be just because everything was so dry early during the spring that we just didn’t have the typical runoff period loading nutrients into the lake that fuel the algae blooms that normally would appear earlier in the season.”
The state Health Department warns that exposure to cyanobacteria — sometimes referred to as blue-green algae — can cause rashes, sore throats or stomach problems. They can also be harmful to pets; a pair of dogs died in Stowe last summer after being exposed. Blooms have been persistent in the state for years, but have become more prevalent recently, leading to some calls for the state to test for toxins in drinking water and around beaches.
Vermont is likely to receive a failing grade from the Environmental Protection Agency on its Lake Champlain cleanup efforts in September. The state has failed to issue its proposed three-acre general permit — the final milestone in the first phase of its phosphorus reduction plan for the lake — which would require retrofits for many properties that have three acres or more acres of impervious surface. Department of Environmental Conservation Commissioner Peter Walke told VTDigger on Tuesday the EPA’s Sept. 4 deadline was “not feasible” for the state.
The city estimates it has had 8,000 visitors in lifeguarded swimming areas since June 20. Alec Keading, the campground and beach manager for the Burlington Parks and Recreation Department, said beaches were especially crowded prior to the July 4 weekend.
“When you talk about global climate change, sometimes people can brush that off because it’s this big globe and it’s a big picture, but here’s a local impact,” Smith said. “If we are seeing the climate change that’s causing Vermont to have more heat more frequently then it is going to have a long-term impact on the lake.”
