Upper Castaic Lake in Los Angeles County has been closed to the public due to an elevated danger algal bloom advisory.
The Department of Water Resources (CDWR) has issued a stern warning, urging residents and visitors to steer clear of any physical contact with the water in the upper part of the Castaic Lake until further notice, as the lake is now plagued by the presence of toxic blue-green algae.
The CDWR states that exposure to toxic blue-green algae, scientifically known as cyanobacteria, can lead to a range of symptoms, including eye irritation, allergic skin rashes, mouth ulcers, vomiting, diarrhea, and cold- and flu-like conditions. In particular, pet owners are advised to be vigilant, as animals are especially susceptible to these toxins.
If physical contact is made with the toxic blue-green algae people are urged to get immediate medical attention and inform those who have been in close contact with them.
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The lower part of the lake, also known as Castaic Lagoon, "has no algal bloom advisory and is open to non-motorized boating," according to the advisory.
For the latest conditions and danger advisory information, go to Harmful Algal Bloom website.