TRENTON, NJ – People who suspect the green stuff on their favorite lake is a harmful algal bloom (HAB) now have a better way to tell the state about it.

The state Department of Environmental Protection (DEP) announced the launching of an interactive HAB mapping tool. The tool allows users to provide the DEP with GPS coordinates and photos of a suspected HAB.

The DEP said it will investigate the reports “to determine if a bloom is occurring and needs to be monitored.” It said the results of those tests will be posted online.

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“The interactive mapping tool also provides the public with location and monitoring data for each HAB event reported to the DEP,” said the state. “This level of detail was available only for Lake Hopatcong and Greenwood Lake in northern New Jersey last year.”

The tool is part of the DEP’s new HAB response plan which expands on the roles and responsibilities of the DEP, the New Jersey Department of Health and the New Jersey Department of Agriculture “particularly regarding public recreational bathing beaches.”

The plan includes details about how the DEP will keep track of HABs through the use of field pigment meters, continuous-monitoring buoys, aircraft remote-sensing, unmanned aerial vehicles and satellite imagery as well as traditional water sampling, said the state.

It said the better information will help its scientists “better target the location and understand the spatial extent” of HABs.

“Members of the public may use the interactive mapping tool from their computers to report suspected harmful algal blooms, which the DEP will then investigate,” said the state. “Using this tool, the public can also view HAB testing data, local alert conditions and other important information about impacted water bodies.”

The DEP said it hopes the tool will provide information that will “help local officials, residents and visitors make better choices about suitable recreational activities in water bodies impacted by harmful algal blooms.”

A New Approach 

HABs on Lake Hopatcong last summer prompted the closure of public beaches and summer-long advisories that contact with the lake water might cause health problems.

The effort drew criticism by some local officials, business and lake area residents. They contended the DEP’s standards were too strict, arguing that state governments elsewhere did not recommend avoiding HABs at the levels found in Lake Hopatcong in 2019.

The input prompted the DEP to come up with a new color-coded HAB alert index and signage system that will be a bit more lenient and nuanced.

“The Murphy Administration is committed to assisting communities that are at risk of being impacted by harmful algal blooms, including by clearly communicating with the public about the locations and risk of HABs,” said DEP Commissioner Catherine McCabe in a press release.

She said the new interactive mapping tool and new health alert index, “greatly improve the quality and flow of information to the public that is essential for safeguarding public health, the environment and local economies that depend on recreation and tourism.”

Too Much Can Be Toxic

The state said HABS are “a growing global problem” noting they “are not caused by true algae but rather by cyanobacteria that in many ways resemble and behave like algae.”

The cyanobacteria, found normally in fresh water, “can proliferate to unhealthful levels in sunlight and hot weather, forming dense mats resembling pea soup or spilled paint. Exposure to cyanobacteria cells can cause a range of mild to moderate health effects, including rashes, allergy-like reactions, flu-like symptoms, gastroenteritis, respiratory irritation and eye irritation,” said the state.

It also noted that ingestion of water containing the toxins these bacteria can produce, known as cyanotoxins, “can result in more serious health effects such as liver toxicity and neurological effects,” and noted that children and pets “are more vulnerable because they ingest more water in relation to their weight.”



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