What you need to know about blue-green algae before heading to CA lakes

FRESNO, Calif. (KFSN) -- Blue-green algae are blooming across the state.

In the Valley, the San Luis Reservoir west of Merced has dangerous levels of toxins, but at Hensely Lake in Madera, the levels aren't as bad.

"We've had some blue-green algae in the lake. The Central Valley Regional Water Quality Control Board has done a few testing, and it appears that the tests that the conditions are getting better," said lake manager Dough Plitt.

Satellite images show the Hensley Lake bloom is much lower than the San Luis Reservoir. Compared to last year, Hensley Lake has seen a significant improvement.

Plitt doesn't want people to shy away from the lake. He says to just be cautious and on the lookout.

"It sometimes looks like a foam mat or a scum on the top of the surface of the water you want to avoid those areas," he said. "Normally the blue-green algae will accumulate in the coves where the water tends to be calmer."

When in doubt, stay out.

The toxins from blue-green algae can have an impact on our furry little friends.

"It a wide range of things from GI upset to skin irritation, all the way to neurological signs and ultimately death. It can happen rather quickly from 15 minutes to a couple hours," said Joshua Smith.

So if your dog manages to swim in it, keep a close eye on their behavior.

"Maybe acting restless, panting, excessive salivation, vomiting diarrhea if any of that starts to occur, get them washed off and get them to a vet as quickly as possible," Smith said.

But so far, Smith as not heard of any dogs in the north valley being sick from blue-green algae.

The California State Water Resources Central Board released the following statement on the blue-green algae bloom:

The Water Boards maintains the HAB Reports Map (https://mywaterquality.ca.gov/habs/where/freshwater_events.html) on the CA HABs Portal that presents voluntarily reports of suspected and confirmed blooms. The number or reports this year are similar to 2018. However, this year we have received more inquiries regarding HABs from local agencies and the public. In early August there were several news reports about suspected blue-green algae poisonings of dogs occurring across the country. We believe that these news reports increased the public's awareness of HABs and has given us the opportunity to engage with the public and share educational resources. We recommend following the HAB Reports Map for updated information on voluntary reports, heeding recommendations on recreational advisory signs, and to learn how blue-green algae blooms visually appear in lakes and streams (visual guide and fact sheets found at: https://mywaterquality.ca.gov/habs/what/index.html).