Press Release: Heat Wave Increases Cyanobacteria Blooms in Lake Champlain

Grand Isle, VT – During the past three days, from September 24-26th, a record-setting heat wave has hit the Champlain Valley late in the recreation season in upstate New York and Vermont. The high temperatures, calm waters, sunshine and the nutrients washed into waterways over the rainy summer have combined to promote cyanobacteria blooms along many shoreline locations and public beaches this week

“Conditions like what we have been experiencing on Lake Champlain over the past week are extremely unusual for this time of year”, said Dr. Eric Howe, Director of the Lake Champlain Basin Program. “These recent weather patterns, combined with a flush of nutrients from the spring and summer storm events, are creating the perfect recipe for cyanobacteria blooms across Lake Champlain. People should be very alert when accessing the lake over the next several days, particularly in the shallow, warm bay areas of the lake that are more likely to have blooms develop quickly.” Warm weather is expected to continue today, though higher wind speeds may begin to disperse the blooms.

What are Cyanobacteria?
Cyanobacteria, or blue-green algae, are a naturally occurring bacteria in marine and fresh water ecosystems worldwide. Under certain conditions, cyanobacteria multiply quickly, creating blooms. Occasionally, these blooms can produce toxins which can make people and pets sick when consumed. Learn more about cyanobacteria (blue-green algae).

Attention Beachgoers: Heed the Warning Signs for Beach Closures
Beachgoers should heed warning notices when a public beach or other area in the lake is closed. Do not enter the water until the beach area is reopened. Even if a beach is not posted as closed, use common sense – when the water appears green or bluish-green or has surface scum, avoid contact with the water, and keep pets and children away from the water’s edge for 24 hours after a bloom dies back.

Cyanobacteria blooms may develop quickly along shorelines especially when the sun is shining, the air is warm and the water is calm – conditions we have experienced for the past several days on Lake Champlain. More than 30 locations reported and verified blooms on Monday afternoon, September 25th. Tuesday brought more of the same conditions. Some blooms only remain in place for a few hours or days and then are dispersed when the weather turns cooler and the wave action breaks up the blooms. In other instances, as with Lake Carmi this summer, the nutrient-rich water continues to provide the cyanobacteria with enough energy to sustain bloom conditions over a longer period of time.

Learn what the harmful blooms look like so you can avoid them. Watch a video of what cyanobacteria bloom look like here.

How do I find out where the blooms are located?
Lake Champlain Basin Program partners have developed an informative Cyanobacteria Tracking Map to show the most recent conditions that have been reported from monitored locations around the lake, mostly by trained volunteers. However, lake monitoring by our volunteer network typically ends in September. For current conditions at a swimming area, contact the local town, Vermont State Parks, or private association responsible for maintaining that lake access point. Conditions shown on this map are based on the most recent information available, including monitoring sites in New York, Vermont and Québec.

Who monitors for cyanobacteria?
The Lake Champlain Basin Program provides funding to support two aspects of cyanobacteria monitoring on Lake Champlain: through the Lake Champlain Long-Term Monitoring Program, in partnership with VT Agency of Natural Resources, NYS Department of Environmental Conservation, and SUNY Plattsburgh. Trained staff collect samples from relatively deep locations from a dozen sites around Lake Champlain. If a site has a full bloom or is developing a bloom, samples are collected and sent to the VT Department of Health Laboratory in Burlington for toxin analysis, and the cyanobacteria species is identified. All sample results, including negative (or “clean” results) are posted on the VT Department of Health Cyanobacteria tracker website.

The Lake Champlain Basin Program also provides assistance to the Lake Champlain Committee which trains more than 100 volunteers each year to sample water quality along Lake Champlain’s Vermont, New York, and Québec shorelines – where people swim and play in and around the water. Samples are collected following established scientific monitoring protocols. If cyanobacteria appear to be present, the monitor also snaps a few photographs of the water and sends this information to the Lake Champlain Committee. The photographs and initial data observations are reviewed by the Lake Champlain Committee staff, and then submitted to the VT Department of Health for posting on the State Cyanobacteria tracker webpage. To view sample photographs of cyanobacteria blooms, visit the Lake Champlain Committee website.

In future years, if you would like to become a citizen monitor for cyanobacteria, please contact the Lake Champlain Committee for more information.

For more information about bloom conditions on other lakes in New York, visit the New York Department of Environmental Conservation Harmful Algal Blooms Notifications Page.

PLEASE NOTE: The information presented in this press release highlights the professional partnership among the Vermont Department of Health, the Lake Champlain Basin Program, the Lake Champlain Committee, and the Vermont and New York Departments of Environmental Conservation to share the most current information with the public regarding cyanobacteria bloom conditions around the lake. We would like to thank all of the municipal, state, and private partners and the more than 100 citizen monitors who help collect, analyze and post this data in a timely manner each summer season.

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