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North Jersey Lake Contaminated, Again, Officials Say

This is the third time since March that the lake has had a harmful algal bloom.

WARREN COUNTY, NJ — A Warren County lake with a history of environmental issues has once again been contaminated, according to officials.

On June 2, a test was conducted in the waters of Liberty Township's Mountain Lake. Results have revealed that a harmful algal bloom (HAB) is prompting an advisory alert level.

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The NJ Department of Environmental Protection (DEP) advises against people, pets, or livestock swimming or wading in the waters at this time. Residents should also avoid drinking the water or eating any fish caught in the lake.

Catch-and-release fishing, as well as boating, is still okay, but experts say residents should use extra caution, especially when kayaking or canoeing.

(NJ Department of Environmental Protection)

Harmful algal blooms occur when colonies of algae "grow out of control and produce toxic or harmful effects on people, fish, shellfish, marine mammals, and birds," according to the National Oceanic and Atmospheric Administration.

The toxic bacteria detected in Mountain Lake are primarily "Aphanizomenon," a species of cyanobacteria.

Consumption or prolonged contact with Aphanizomenon can cause skin and eye irritation, hay fever-like symptoms, and flu-like reactions, according to the U.S. Environmental Protection Agency.

This is the third time Mountain Lake has been under a HAB advisory this year.

Click here to view updates on Mountain Lake's algae status.

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