MADERA COUNTY, Calif. (KFSN) -- Madera County health officials are sharing a warning about Hensley Lake.
Staff with the Central Valley Water Board reported high amounts of harmful algae over the weekend.
These signs are now placed around Hensley Lake at the Buck Ridge boat ramp, warning people about harmful algae in the water.
Patrick Greco visits Hensley Lake with his dog, Riley, at least once a week for some peace and quiet, but seeing these warnings worries him.
Greco said, "That's kind of concerning a little bit. It hasn't been that bad in the years but now that they are putting up signs, it's a little bit more concerning to me."
Parents and pet owners are advised to not let their children or animals go into the water at all. Toxins from algae can harm people, and kill animals if ingested.
Health officials say adult visitors can swim, but need to stay away from any visible algae in the water.
"I know not to drink the water and stuff like that, but my dogs out here splashing and drinking away and that concerns me because it might mess up her stomach," Greco said. "To think that it could maybe destroy something that I love is pretty hurtful."
Officials say, typically, algal blooms occur in late summer or early fall.
When nutrients are right in the water, the bloom can grow and during that process is when it can release the harmful cyanotoxins.
Because the water is lower, there's not a lot of boat activity to move the water around, so this bright green algae is concentrated in coves. Officials warn visitors to avoid those areas.
If you start exhibit any symptoms, then seek medical attention.
Doug Plitt is Operations Project Manager with the U.S. Army Corps. of Engineers at Hensley Lake. He said, "Your skin may be irritated, you may notice a rash developing. If you've ingested it, typically you'd get a dry mouth, possibly nausea or vomiting, a headache, or diarrhea."
The EPA is saying warmer weather due to climate change might make harmful algae a bigger concern.
Dr. David Caron with the University of Southern California said, "In many water bodies around the country, not just in California, we are reaching a tipping point."
The Central Valley regional water quality control board will continue its routine water monitoring..
Water has to be clear of algae for two weeks in order for the advisory to be lifted.
For more information and resources, click here.
Harmful algae bloom found in Hensley Lake, officials urging caution
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