State officials are urging residents to avoid swimming or coming in contact with Lake Hopatcong after cyanobacteria blooms were confirmed this week by aerial surveillance.
According to the state Department of Environmental Protection, exposure to the blooms can cause reactions including skin rashes and eye irritation, while ingesting contaminated water could lead to abdominal pain, nausea and vomiting.
In recent days, the state has received multiple reports of people experiencing mild skin rashes after coming in contact with the lake water.
The DEP is advising the public to avoid swimming, wading, and water sports and not to eat fish caught in the lake or allow pets to come in contact with or drink lake water. Anyone who comes in contact with a bloom should rinse off with fresh water as soon as possible.
Often referred to as blue-green algae, cyanobacteria are not true algae but are capable of rapid growth by photosynthesis. According to the DEP, the blooms may be a result of recent heavy rainfall carrying stormwater runoff into the lake, followed by periods of warm weather that allowed the bacteria to grow.
The agency will continue monitoring bacteria levels until the lake is determined to be safe for recreational contact.