Massive algae bloom covers Diamond Valley Lake

DIAMOND VALLEY LAKE, Calif. (KABC) -- The gates to Diamond Valley Lake are closed Monday, which is no surprise, but when the marina reopens Tuesday, boaters and fisherman will be greeted with something that many haven't seen in a while: a massive algae bloom.

"It covers about two-thirds of the lake and goes down a few meters," said Mic Stewart, water quality manager for Metropolitan Water District, which operates the reservoir. "But it's basically on the surface you're out there looking at it, it's a very green matte, but it's very noticeable."

MWD estimates this is the largest algae bloom ever seen on the lake. Swimming isn't allowed anyway, but officials are urging people not to touch the water, and to use extra caution when consuming fish caught from the lake.

"When you clean the fish, and throw away the guts, just rinse off the surface of the fish before you cook it," Stewart said.

Diamond Valley Lake is located south of Hemet and has been in operation since 1999. It's the largest reservoir in Southern California. For the time being, MWD says it won't be removing water from the lake to be used for drinking purposes. But it does have the technology to do so safely, if necessary.

"We have what's caused an outlet structure, and in that structure we have tiers meaning we can remove water from different levels of the lake," Stewart said. "And that's a great feature to have because at lower levels the water can be much better."

MWD said unfortunately the bloom is so large there's not much that can be done about it right now. So how long will this bloom be around?

"Unfortunately, the way algal species work is they just have to run their course," Stewart said. "It may be a few days, a week, we just don't know."

It's something people should keep in mind when making their Fourth of July plans.