Is Lake Lanier safe for swimming? Several groups test the water regularly to answer that question, keeping their eyes open for high levels of chlorophyll-a and E.coli. 

Testing for E. coli

Chris Arthur, chief ranger over recreation with the U.S. Army Corps of Engineers, said the corps tests all of its beaches on Lake Lanier from March through September, specifically tracking the amount of fecal coliform, which indicates the possible presence of E.coli and disease-causing microorganisms. If a sampling shows a high level, Arthur said a corps member will retest the site to make sure they don’t have a faulty reading. If the data comes in high again, he said the public will be notified through a press release, and the corps will close the beach. 

The corps conducts water quality tests at its 18 different beaches around Lake Lanier, some of those include Buford Dam Park, Old Federal Day Use Park, Burton Mill Park and Duckett Mill Campground. Arthur said samples will be taken a few days before Memorial Day and soon after the holiday weekend. All the corps-run beaches are open.

“I can’t remember us doing it (closing a beach because of fecal coliform levels) last year or the year before, but we have done it in the past,” Arthur said. 

Brian Wiley, environmental services manager with Gainesville Water Resources, said his department tests the water bi-weekly at Gainesville’s Clarks Bridge Park and Holly Park and Hall County’s River Forks Park. The samples are collected to analyze E.coli levels.

“We provide all test results to each park owner,” Wiley said. “If the results exceed the bacteria threshold, the Parks would individually decide and shut down the beach.”

River Forks was closed in 2019 due to bacteria levels. Parks director Mike Little said at the time that Canada geese were likely to blame for the bacteria.

Chattahoochee Riverkeeper conducts monthly monitoring of nutrient levels in Lake Lanier from April through October, using the data to offer an annual average of the area. Dale Caldwell, headwaters director, said they take samples at 10 different locations. He shared that bacteria levels can vary from day to day, depending on the rainfall and wildlife — such as geese — that inhabit the water. 

Because of runoff from streets, fields and other man-made surfaces, bacteria counts tend to spike after rainfall as the dust, fertilizer and other debris flow into creeks and rivers, which end up in Lake Lanier.

“We won’t know the results until 24 hours, and even when we get the results, a rain event can turn around and change that quickly,” Caldwell said. “That information is no longer helpful or even accurate.”

Jennifer Flowers, executive director of the Lake Lanier Association, said the safest bet is to avoid swimming 48-72 hours after rainfall and not enter areas with visible goose droppings.

“That (after rain) is going to be when your bacteria count is highest,” Flowers said. “Bacteria doesn’t thrive in Lake Lanier, but it is introduced from the rivers and tributaries that come into the lake. If you give it time to clear up after rainfall, that bacteria count goes back down to normal.”

Watch for toxic algae

Flowers said members of the Lake Lanier Association test 27 different sites on the lake monthly to track the year-round algae growth. Flowers noted that the collected data doesn’t indicate water quality from a health perspective but it can help show any potentially harmful levels of algae in the body of water. 

Last year in the late summer and early fall, she said the association received nine reports in isolated areas on Lake Lanier of toxic blue-green algae, also known as cyanobacteria.  

Flowers said cyanobacterial blooms tend to thrive when the conditions are warm and sunny. Luckily, people can easily spot them for their bright green color, which Flowers describes as looking like “spilled paint.”

“There are lots of different species of algae found in Lake Lanier that’s needed and a part of the food chain,” she said. “We just don’t want to see that harmful cyanobacteria in high levels.”

People can encounter this potentially harmful bacteria by swallowing contaminated water, eating seafood contaminated with toxins, breathing in toxins that are in air particles or through direct contact, such as swimming or boating, according to the Centers for Disease Control and Prevention. Exposure may cause such problems as nausea, vomiting, diarrhea, sore throat, pneumonia, dermatitis and conjunctivitis, the agency says.

Looking at Lake Lanier Association’s recent tests for chlorophyll-a, Flowers said there’s nothing to be concerned about. 

“None of these numbers we have are out of safe range,” she said. “Even when we say Lake Lanier’s algae levels are high, it’s still safe to swim in it. We’re so far below the unsafe.”

Flowers explained that the chlorophyll-a levels vary across Lake Lanier throughout the year and are dependent upon temperature, rainfall, available nutrients and sunshine. She added that the state standards for those levels are different in parts of the lake, taking into account the amount of water and nutrient balance. For example, the numbers can be higher farther north because there’s not as much water. The unit of measurement is in micrograms per liter, which is equivalent to parts per billion.

Flowers said the Georgia Environmental Protection Division has set standards at five different locations in Lake Lanier, including Lanier Bridge and Bolling Bridge with 10, Browns Bridge 7, mid-lake 6 and Buford Dam 5.

Flowers asks those who see an issue on Lake Lanier, including an algal bloom, abandoned dock or other potential hazard to go to lakelanier.org and choose the “report a problem” option and document what they’ve witnessed. 

“There’s 39,000 acres of Lake Lanier — we can’t be everywhere at once,” Flowers said. “So, if anybody is out there, the biggest thing is have your eyes open and let us know what’s going on.”

Wear a life jacket

As people flock to the lake, Arthur reminds visitors to don a life jacket when out in the water. 

“We’re coming up on a busy year, our parks and beaches will be full,” he said. “We don’t want any drownings. We want people to swim safely and stay within designated swim areas.”

There have been three drownings so far this year, including a Cumming teen authorities say was swimming across a cove, a Greenville, South Carolina, man who did not resurface after swimming and getting separated from a rented pontoon boat and a Stockbridge boater. About 12 million visit Lake Lanier annually.

For those who don’t have a life jacket, Arthur said the corps keeps “life jacket loaner stations” on each of its beaches. People are encouraged to borrow them and return them to the structure when they’re done. Each station keeps 12-15 life jackets of various sizes. 

“It’s a wonderful place to go and enjoy,” Flowers said of Lanier. “The biggest thing with safety is to always wear a life jacket in the lake. Even the best swimmers can get into trouble.”