ROXBURY, NJ – Only four of the 22 sites on Lake Hopatcong sampled for Harmful Algal Bloom (HAB) levels on Tuesday showed bacterial concentrations above the state’s advisory levels, the fewest since July 1.

HAB colony counts above that level – 20,000 cells/mL – were found at Hopatcong State Park (35,000), Crescent Cover River Styx (52,000), Henderson Cove (32,000) and Byram Cove (28,000) according to the state Department of Environmental Protection (DEP).

The DEP’s advisory against coming into contact with water from anywhere in the lake remains in effect and people are advised to keep pets away and to not eat any fish they catch.

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The latest aerial survey of the lake revealed good news for the many people hoping to see an end to the HAB, which has crippled many businesses around the lake and ruined summertime fun for thousands. The Thursday flight showed that estimated levels of the bacteria in the HAB – “seem to have significantly decreased in spatial coverage,” the state said.

It said the highest levels detected by the equipment in the aircraft were in River Styx.

Bad News for Another Boating Haven

For lake lovers who figured they could get their fun by heading north to Greenwood Lake, the DEP has some bad news: That lake, just a little smaller than Lake Hopatcong, is now also impacted by a HAB.

In fact, the one at Greenwood Lake is worse, in terms of danger, than Lake Hopatcong’s, according to DEP information. Four areas tested for cyanobacteria showed cell counts ranging from 61,000 to 212,000.

And while the levels of microcystins – dangerous toxins created by cyanobacteria – have yet to reach the DEP advisory level of 3 ug/l for Lake Hopatcong, tests of Greenwood Lake found levels as high as 4.50 ug/l on July 15.

People continue to swim, water-ski, canoe and do other activities in Lake Hopatcong despite the closure of public beaches for swimming and the continued warnings by the state. Many are also urging the state to do something to remove the bacteria.

The state says nothing can be done.

“There is no scientifically sound treatment to eliminate HABs from water bodies, so advanced and continuous monitoring is the key element in protecting health and assessing when the lake is safe for swimming and recreational activities,” said the DEP in a statement.

It said it continues to urge people “to avoid swimming or water sports that may result in contact with the water, such as water-skiing, tubing, canoeing and kayaking,” but noted “there is no recommended limitation on fishing or passive recreational boating that does not have the potential for splashing.”