Bacteria levels from the HAB are nearly 10 times higher than the state health standard, water samples taken Monday show.
Cyanobacteria levels from the New Jersey side of the lake were 212,000 cells per milliliter (state standard is 20,000 cells per milliliter), DEP lab results show.
The lowest sample taken showed 90,000 cells per milliliter, and that was taken from the middle section of the lake.
The northern section showed 61,000 and Browns Point, a park on the West Milford lake, was 148,000.
Swimming, wading and water sports are banned in the Passaic and Orange County lake, local officials said.
Skin and stomach problems could develop for those who come in contact with the water.
Fish caught in the lake should not be eaten.
Lake Hopatcong was closed due to a HAB in June. It remains closed.
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