UVM researchers study climate change’s impact on toxic algae blooms in Lake Champlain

SWANTON, Vt. (WCAX) - Researchers at the University of Vermont have released a study about the links between climate change and blue-green algae blooms in Lake Champlain.

It’s a bummer for sunbathers and swimmers each summer -- closed beaches as a result of cyanobacteria. And it’s no secret that high concentrations of nutrients like phosphorous and nitrogen are to blame for the recurring blue-green algae.

“When they mix in with warmer water temperatures, they create this kind of perfect soup for cyanobacteria and algae to grow,” said Dr. Asim Zia, a professor of public policy and computer science at UVM.

In shallow areas like Missisquoi Bay, water can become stagnant. Couple that with legacy nutrients from historical farming in the area and you have a breeding ground for the toxic blooms. But Zia says it’s not exclusive to the northern part of Lake Champlain. “Of course right now this study is about the shallow lakes and Missisquoi Bay, but our studies also indicate that if we do not take action now, the deeper parts of the lake would also be affected in (the) future,” he said.

The blooms have become more of an issue as increasing extreme events like flooding and drought are triggered by climate change. “In this particular study, we find that when there are more droughts -- especially during the summer months and coupled with these legacy nutrients -- we get more and more incidences of cyanobacteria blooms,” Zia said.

Increased blooms are a result of poor water retention on the land causing nutrients to be dumped into waterways because of urbanization, bad soil management, or lack of vegetation. That’s why researchers say the frequency of cyanobacteria blooms will only increase with time. It’s inconvenient for those who want to recreate on the lake, hurts the tourism industry, and impacts property values. But it also impacts people who need the lake for livelihood, including local Abenaki subsistence users and towns who use the lake for drinking water.

“Our goal is to make sure in the face of these climate change-induced threats to water quality, we are able to sustain clean water. And we can stop this pollution at the source, not at the end of the pipe,” Zia said.

That’s why researchers like Dr. Zia are calling on Vermonters, New Yorkers, and Canadians to start accounting for more extreme weather events and the impacts they’ll have on the lake. In this case, that looks like conservation of forestlands and increased green infrastructure to stop nutrient dumping into Lake Champlain. “Typically, people say that climate change is going to affect the polar bears or people in Bangledesh or people in Caribbean. This shows that climate change is having impacts in our backyard,” Zia said. “It’s a global-scale problem, and people in say, U.S. or Canada have a lot of capacity to put in resources for cleaning the water. You can imagine many other parts of the world where they don’t have the resources to clean the water. Climate change is going to also make those lakes and rivers vulnerable to these kinds of threats.”

He says the research team is currently working with citizen scientists, the Abenaki, and those in charge of water quality for towns. They say there is no silver bullet for this issue and it requires a collective effort from everyone.

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