New tool to fight Lake Mohegan algae must wait, after small barge flips over

YORKTOWN - Lake Mohegan could have few, if any, days of swimming bans if a new tool in the battle against toxic algae proves successful. 

But the battle is on hold for now. Contractor Princeton Hydro was set Tuesday to start applying the new tool — aluminum sulfate, or alum — to the 103-acre lake. However, its small pontoon barge flipped over in the water, said Ken Belfer, president of the Mohegan Lake Improvement District, which sought the state's pilot project to test the use of alum against algae blooms.

Belfer said there were no injuries and no hazardous spills, but electronic equipment on board may have been affected. He said Wednesday there was no new date yet from the state for treatment to start, but that one possibility is Princeton Hydro does the water testing and a different contractor applies the alum to the lake. 

The two-day treatment regimen at the lake in the town's northwestern corner is a pilot program by the state Department of Environmental Conservation. It will include two years of studying the effectiveness of alum against the algae, which release toxins that are a threat if touched or ingested.

High levels of the toxins can cause diarrhea, vomiting, skin, eye or throat irritation, allergic reactions, and breathing difficulties, according to the state Department of Health.

Thousands of residents live around the lake, using beaches along with their guests. 

The Mohegan Lake Improvement District, a tax district of homeowners formed to improve the lake's quality, has experience a lake "plagued with the blue-green algae blooms for decades and decades," said Belfer. "This treatment could be a game changer for Lake Mohegan, immensely improving the water quality in the summer beach season, and eliminating the potential health risks from the blue green algae blooms."

HYDRILLA: Croton-on-Hudson battles invasive plant in the river

BLUE-GREEN ALGAE: Blooms plague area lakes

TOXIC: Blue-green algae targeted at 3 Putnam County lakes in state's $65M battle

NEW JERSEY lakes need to go on a diet. Too much phosphorus causing harmful algae blooms

Development around the lake, including use of certain fertilizers, creates high phosphorus levels in the sediment on the lake bottom, Belfer said. The phosphorus feeds algae growth, becoming a problem in the summer because higher temperatures also contribute to the growth.

When alum is added to the water, it binds "the phosphorus to prevent it from feeding the algae," Belfer said.

Alum is already being used in other states and countries. So last winter, the improvement district asked to have Lake Mohegan do the pilot program for the state. Peach Lake in North Salem is also part of the program.

"We're not the only lake by any means that's dealing with excessive phosphorus levels," Belfer said.

Belfer and officials gathered earlier Tuesday at the lake to announce the start of the treatment.

“We must leave the next generation healthy waterways," state Sen. Pete Harckham, who attended, said in a statement. "I want to congratulate the people from the Mohegan Lake Improvement District for their tenacity and hard work over many years to make this pilot program a reality."