Candlewood Lake, Squantz Pond Report: Is it Safe to Swim?

Danbury, CT — Blue-green algae— that foamy, bubbly, scummy nuisance is rearing its ugly head once again at local swimming areas causing closures.

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Last year town beaches didn't close in Sherman and New Fairfield until August, this year beach closures began in June starting with New Fairfield, which was closed for the blue-green algae blooms, a concern for many in the area.

What is blue-green algae?

Connecticut's Department of Energy and Environmental Protection said that blue-green algae, also known as cyanobacteria, is a collection of microscopic organisms that, when "in bloom," may produce and release toxins. During a bloom the water may be cloudy or thick like pea soup and the water will be green or brown, according to the CT DEEP.

What are the potential health risks from exposure?

People who may be exposed to toxins by ingesting water, contact with skin or inhalation of water droplets may experience irritation of the skin, nose, eyes and respiratory tract, gastrointestinal upset such as vomiting or diarrhea upon ingestion, liver or nervous system effects, the CT DEEP said.

Dogs are especially at risk because they may also drink from the tainted water and be exposed when they groom themselves after leaving the water.

Where are they being found?

So far this year they've been seen at New Fairfield's town beach. Last year blooms were seen in Brookfield and Danbury, causing closures in July and August.

Why are the blue-green algae blooms popping up so early this season?

"That's the $64 million question," said Larry Marsicano, Executive Director of the Candlewood Lake Authority (CLA). "Why are we having some of these frequent early blooms?"

Marsicano said the CLA recently partnered with Western Connecticut State University (WCSU) to answer that question by launching a pilot program that monitor bacteria levels on the five lake towns of Brookfield, New Milford, Sherman, New Fairfield and Danbury. Part of their research is to see if the blooms produce cytotoxins found in blue-green algae blooms which can be harmful to humans and pets.

Dr. Ed Wong is working with the CLA, who helped secure foundation grants from the Harcourt Foundation in New Milford, the Merserve Memorial Fund and area lake towns to cover the cost of the program.

The procedure for testing swimming areas used to be that beaches would close based on visual inspection at the sight of an algae bloom. With the new pilot program, the CLA and WSCU are proactively taking water samples.

"We typically never experienced [algae blooms] so early in the season," Marsicano told Patch. "The timing and frequency is all over the map. We're trying to provide the health directors something else to go on to understand what to go on to understand what the risks are."

What's causing the blue-green algae blooms?

"We're into a new age here with this— maybe climate change. Algae blooms historically with high nutrient levels. This is not the lake that it was in the 50s, 60s or early 70s. There has been rapid growth in the area," Marsicano said.

Septic systems, storm water runoff and climate change are all possible causes, Marsicano said, and is why area towns have written regulations into their zoning laws.

Is it safe to swim?

Local town beaches are considered safe to swim and can reopen when toxin levels are below 15 parts per billion, Marsicano said.

The Candlewood Lake Authority posted the test results Friday from the Western Connecticut State University Cyanotoxin Monitoring Program that show the levels are "well below the threshold."

• Danbury Town Park - 0.22 ppb
• New Fairfield Town Park Sample 1 - 0.2 ppb
• New Fairfield Town Park Sample 2 (second location) - 0.35 ppb
• Sherman Town Park - 0.35 ppb
• Squantz Pond State Park - 0.13 ppb
• Lynn Deming Town Park New Milford - 0.219 ppb
• Brookfield Town Park's test results will be posted Friday afternoon, according to the CLA
• Newtown, Monroe, Oxford, Southbury: Lake Zoar's test results will be posted Friday afternoon, according to the CLA

Squantz Pond was closed Thursday due to the presence of e. coli bacteria. The beach reopened on Friday.

The Candlewood Lake Authority and WCSU's new monitoring program tests Candlewood Lake and Lake Zoar.

To check if your local beach or lake is safe to swim, click here or check with your town's health department.

Photo by Candlewood Lake Authority