Water testing at Lake Hopatcong, one of the most popular summer lakes in New Jersey, has once again found a high concentration of harmful algae blooms.
If ingested, the bacteria can cause headaches, abdominal pain, and nausea. The state will retest the water once follow-up samples show lower concentrations of the algae.
The algae bloom at the 4-square-mile lake, which straddles the border of Sussex and Morris counties, comes after it was closed in 2019 for another harmful bloom.
In that case, the lake was shut down for all activities in June and stayed closed through the July 4th holiday, as officials at that time warned the closure could last weeks, or even longer. Several people also got mild skin rashes from touching the water.
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