Pyramid Lake reopens, but toxin still a risk

Visitors to Pyramid Lake are allowed to go back into the water, though state water officials caution they should still enter at their own risk after a large algae bloom pumped toxins into the lake last month.

The blue-green bloom was detected in late June and prompted the closure of the lake to swimming for weeks. Blue-green algae flourish in warm temperatures, calm conditions and plenty of sunlight, according to the state Department of Water Resources.

The algae produce a toxin that in high concentrations can cause skin rashes, irritate the eyes, nose, mouth or throat, and trigger headaches and gastrointestinal issues. The toxin levels have dropped enough that the department said all recreational activity is allowed, though visitors are urged to use caution.

Boiling the water does not remove the toxins — so don’t drink it, the agency said.

Swimmers must also stay away from algae and its scum, it said.

Eating fish or shellfish from the lake is not recommended, but if a person is going to eat marine life from the water, authorities say, the guts and liver must be removed and the fillet washed clean with fresh water.

Blue-green algae appear as bright green in the water, with streaks that look like spilled paint. They can also appear as blue-green, white or brown foam or scum that can float on the water or accumulate along shore, state officials said.

Pyramid Lake is north of Castaic Lake in Los Angeles County along the 5 Freeway.