Harmful algae blooms keep water sports on hold at lakes in NJ, NY, and PA

By James M. O’Neill, North Jersey Record

STORY HIGHLIGHTS

• Lake Hopatcong’s phosphorous levels this June are the highest in 17 years of data .
• Exposure to the toxins that the cyanobacteria create can cause a range of health effects, including rashes, allergy-like reactions, flu-like symptoms, gastroenteritis, respiratory irritation, skin rashes and eye irritation.

The kind of weather New Jersey gets in the coming days will determine whether the dangerous algae blooms affecting Lake Hopatcong and Spruce Run Reservoir will last days, weeks — or much of the summer.

A stretch of sunny days could help cause the blooms to crash, said Fred Lubnow, an aquatic and watershed management expert with Princeton Hydro. Or, a major storm with lots of rain could help flush the lakes clean.

But a continued pattern of short, intense storms followed by warm days could set the lakes up for persistent algae blooms through the summer, he said.

The state has bathing beach closures in effect for Lake Hopatcong, New Jersey’s largest lake, bordered by Sussex, Passaic and Morris counties, as well as at Spruce Run Reservoir in Hunterdon County — putting a damper on this weekend’s water sports activities there.

The current bloom in Lake Hopatcong “is the first of this magnitude in New Jersey,” Bruce Friedman, director of water monitoring at the state Department of Environmental Protection, said Friday evening. “We’ve never seen a bloom that covers a majority of a New Jersey lake.” Usually they have been limited to a specific cove.

“How long the bloom will persist is impossible to estimate,” Friedman said. “Some blooms in the past have persisted into the fall. Hopefully that won’t happen here, but it is a possibility.”

Spruce Run Reservoir in Hunterdon County has had bathing beach closures because of a harmful algae bloom (Photo: Chris Pedota /The Record)

So far this year the harmful blooms have also hit Deal and Sunset lakes in Monmouth County, and Swartswood Lake and Lake Mohawk in Sussex County.

The problem has also cropped up in lakes in New York and Pennsylvania. “This has been a regional phenomenon,” Lubnow said Friday.

“One reason is that last week we got a lot of intense short storms where it rained heavily for 20 to 30 minutes and then stopped and were followed by 80-degree days,” he said. “That rinsed the watershed of nutrients, which went into the lakes, where they sat.”

Those nutrients – mainly phosphorous – provided an abundance of food for the algae to feed on. The blue-green algae, or cyanobacteria, prefer three conditions to bloom – warmer water, still water and elevated nutrient concentrations.

More: $119 Billion plan to protect NY/NJ from another Sandy raises concerns over impact, cost

More: Stranger Jersey: The Monster of Lake Hopatcong

Smaller lakes have not been as affected this year so far because even during short rain storms the water level will spill over the lakes’ dams, helping to clear out the algae and nutrients.

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