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Posted Monday, July 15th, 2019

Swimming and Water Contact Advisory Remains in Effect — IMPORTANT: Boating Allowed–Restaurants Open

The state Department of Environmental Protection and U.S. Geological Survey have deployed high-tech, real-time monitoring buoys as part of a comprehensive response to the widespread Harmful Algal Bloom affecting Lake Hopatcong.

While there is no scientifically sound treatment to eliminate these blooms from the water, the DEP believes that advanced and continuous monitoring is a key element in protecting health and assessing when the lake is safe again for all recreation. However, the state says there is no suggested limitation on more passive boating that does not involve bodily contact with lake water.

Boating is allowed on Lake Hopatcong but DEP advisory cautions against recreational sports, such as water skiing, and direct contact with the water

Boating is allowed on Lake Hopatcong but DEP advisory cautions against recreational sports, such as water skiing, and direct contact with the water

Also, lake area officials have stressed that local restaurants and other businesses remain open, and they are encouraging area residents to visit.

“We share the frustrations of local residents, business owners and leaders about the widespread extent of this bloom and the impact it is having on the health of Lake Hopatcong and the local economy,” said DEP Commissioner Catherine R. McCabe. “These buoys will help us to better understand what is causing the Harmful Algal Blooms and may help us predict conditions that may cause future blooms.

“To help prevent these occurrences, it is important that residents and municipalities do whatever they can to help reduce the flow of nutrients to the lake, including improved stormwater management, routine septic system cleaning and reduced use of fertilizers.”

The DEP last week deployed a real-time water monitoring buoy and the U.S. Geological Survey has deployed a second buoy. They will gather a wide range of water quality data, including phycocyanin pigments that are indicative of Harmful Algal Blooms, turbidity, salinity, dissolved oxygen, temperature, chlorophyll and pH.

Click here for DEP real-time monitoring data for Lake Hopatcong. Click here for USGS real-time data.

The buoys were deployed at two locations in the center of the lake, which is known locally as the main lake. This is the first time these types of buoys have been utilized in a lake in New Jersey. They will feed data constantly to DEP by way of cellular communication.

photo shows buoy deployed in Lake Hopatcong

Buoy deployed in Lake Hopatcong

The data they collect will supplement data the DEP has been collecting along shorelines, from boats, and from a state-of-the-art sensor used during weekly aerial surveillance. Monitoring will continue as long as necessary. Surface water samples will be collected every Tuesday and Thursday, with results posted to the DEP’s HAB website the following day.

“We are committed to using all the tools at our disposal so that we can make strong, science-based decisions that will protect public health, help us understand when the bloom may dissipate, and keep the public informed,” said Division of Water Monitoring and Standards Director Bruce Friedman.

The DEP continues to advise that public beaches remain closed and that the public avoid swimming and water sports that may result in contact with water, such as jet-skiing, water-skiing, canoeing or kayaking. The DEP also advises that fish caught in the lake should not be consumed and that pets should not be permitted to drink or come in contact with the water. There is no recommended limitation on passive boating that does not involve bodily contact with the water.

Cyanobacteria levels in the lake remain above the state’s Health Advisory Guidance level.  Exposure to cyanobacteria can cause a range of health effects, including rashes, allergy-like reactions, flu-like symptoms, gastroenteritis, respiratory irritation and eye irritation. More sensitive individuals can experience these health effects even at levels below the state’s guidance.

The reasons for the rapid spread are not known, but it may be due to stormwater runoff from heavy and persistent rainfall carrying nutrients into the lake followed by warm weather. These conditions may have caused naturally present cyanobacteria to grow rapidly. Primary sources of nutrients include septic systems, lawn fertilizers and animal wastes.