The Department of Environmental Protection's harmful algal bloom advisory has been lifted for six bathing beaches in the area of Lake Hopatcong stretching from Byram Bay to Halsey Island.
The DEP and New Jersey Department of Health have advised local health officials that the following beaches can reopen: Pebble Beach, Sand Harbor, Bass Rock Beach, Sperry Springs Beach, Beck Lane Beach and CAPP Beach.
The six beaches have met the state's Health Advisory Guidance levels for two consecutive sampling rounds.
The Byram Bay Community Club Beach and Clearwater Beach in the area remain under advisory and closed pending further water sampling Thursday.
The beach at Hopatcong State Park at the southern end of the lake remains closed. They have not yet met the requirement, but all attempts will be made to safely open them this weekend if testing data supports the action.
Harmful algal blooms, also known as blue-green algae, are usually a bright green, but can also appear as spilled paint, "pea soup," or as having a thick coating or "mat" on the surface. These blooms are not true algal blooms but are caused by any of various species of cyanobacteria.
Cyanobacteria measurements taken on Monday ranged from 4,500 cells per milliliter at CAPP Beach to 18,625 cells per milliliter at Pebble Beach. The state Health Advisory Guidance level is 20,000 cells per milliliter. Toxin levels at each of the beaches are below the 3 micrograms per liter.
Exposure to a harmful algal bloom can cause a range of health effects, including rashes, allergy-like reactions, flu-like symptoms, gastroenteritis, respiratory irritation and eye irritation. Exposure to a harmful algal bloom that is actively producing cyanotoxins may result in more serious health effects, including liver toxicity and neurological effects.