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Posted Friday, June 28th, 2019

DEP Advises Public to Avoid All Contact with Lake Hopatcong Water, Especially Children and Vulnerable Populations

The state Department of Environmental Protection is advising the public to avoid swimming in or contact with Lake Hopatcong water due to an extensive Harmful Algal Bloom, or HAB, confirmed this week by aerial surveillance. Exposure to the water can cause a range of negative health effects.

Photo of Lake Hopatcong shows algal bloom

Photo of Lake Hopatcong shows algal bloom

The DEP’s Division of Water Monitoring and Standards’ aerial surveillance has confirmed that large areas of Lake Hopatcong are experiencing cyanobacteria blooms. The DEP will monitor cyanobacteria levels until the lake is determined to be safe for recreational contact.

Recreational exposure can occur while swimming, wading and during watersport activities such as jet skiing, kayaking, wind-surfing and paddle-boarding. The DEP is advising the public to avoid these activities and all contact with water from Lake Hopatcong until further notice.

Below are some basic Q & As to help guide residents on the situation. Also, read the DEP’s press release. Please reach out to your local municipality or health provider for answers to more specific questions.

Lake Hopatcong Algal Bloom Issue

Q: Is Lake Hopatcong Closed to the Public?

A: No. It is open but the state DEP advises against swimming in or drinking the water?

Q: What is the problem?

A: Lake Hopatcong is experiencing cyanobacteria blooms. The rapid spread of the bloom may be the result of heavy rainfall carrying nutrient-laden stormwater into the lake, followed by periods of warm weather.

Q: How long will this problem last?

A: It is unclear. This naturally occurring situation could last for weeks.DEP's Lake Hopatcong Water Advisory Remains in Place: Q&A on Key Issues

Q: What is the state doing to resolve it?

A: There is no known antidote other than letting nature take its course. DEP will do regular water monitoring and lake flyovers to continually assess the situation.

Q: What happens with contact to the algae?

A: Exposure can cause a range of health effects, including rashes, allergy-like reactions, flu-like symptoms, gastroenteritis, respiratory irritation, skin rashes and eye irritation. You should see your doctor if you experience any of these ailments.

Q: Can I swim in the water?

A: The DEP advises the public to avoid all contact with water from Lake Hopatcong.

Q: Can I fish at Lake Hopatcong?

A: Yes, but the DEP is advising residents not to eat fish caught in the lake.

Q: What about my pets?

A: The DEP advises against allowing pets to swim in the lake water or drink lake water.

Q: Can I boat on Lake Hopatcong?

A: Yes, enjoy your boat. But avoid watersport activities, such as jet skiing, kayaking, wind-surfing and paddle-boarding.

Q: What if I have questions?

A: Contact your town hall or municipal health department, whose officials are in direct contact with the state.  Look for updates on the DEP website or municipal websites in Hopatcong, Jefferson, Mt. Arlington, and Roxbury, plus the Lake Hopatcong Commission and Lake Hopatcong Foundation.