Public Urged to Avoid Water Contact at Pyramid Lake: Danger Advisory issued for Harmful Algal Bloom


Image of Vista del Lago Visitor Center at Pyramid Lake in Los Angeles County.

Image of Pyramid Lake in Los Angeles County. DWR/2019

SACRAMENTO, Calif. – Pyramid Lake and Los Alamos Campground in Los Angeles County reopen tomorrow, September 23 to the public following a temporary closure per a United States Forest Service order to ensure public safety due to widespread wildfires in California. Due to the presence of harmful blue-green algae at Pyramid Lake, the Department of Water Resources urges everyone to avoid physical contact with water until further notice. The swim beaches will be closed and the public should avoid eating fish from the lake.

A danger advisory was put in place at Pyramid Lake and remains in effect for the entire lake until further notice. It is advised to stay out of the water and avoid contact with algal scum in the water or on shore. Swimming and other water-contact recreation and sporting activities are not considered safe under the danger advisory due to potential adverse health effects. For more information on a danger advisory, go to Harmful Algal Bloom website under Advisory Signs.

Advisories are based on the potential health risks from algae toxins. Exposure to toxic blue-green algae, also known as cyanobacteria, can cause eye irritation, allergic skin rash, mouth ulcers, vomiting, diarrhea, and cold- and flu-like symptoms. Pets can be especially susceptible because they tend to drink while in the water and lick their fur afterwards. Keep pets away from the water.

Bloom conditions can change rapidly, and wind and waves may move or concentrate the bloom into different regions of the reservoir. The algal bloom can accumulate into mats or form scums or foam at the surface and along the shoreline, and range in color from blue, green, white, or brown.

State guidelines on cyanobacteria and harmful algal blooms recommend the following precautions be taken in waters impacted by blue-green algae:

  • Take care that pets and livestock do not drink the water, swim through algal blooms, scum, or mats, or lick their fur after going in the water. Rinse pets in clean water to remove algae from fur.
  • Avoid wading, swimming, or jet or water skiing in water containing algae blooms, scum, or mats.
  • Do not drink, cook, or wash dishes with untreated surface water from these areas under any circumstances. Common water purification techniques such as camping filters, tablets, and boiling do not remove toxins.
  • Do not eat mussels or other bivalves collected from these areas. No fish should be consumed under a danger advisory.
  • Get medical treatment immediately if you think that you, a family member, friend, pet, or livestock might have been poisoned by blue-green algae toxins. Be sure to alert medical professionals to the possible contact with blue-green algae. Also, make sure to contact the local county public health department.

For more information, visit:



Maggie Macias, Information Officer, Public Affairs, Department of Water Resources

(916) 653-8743 |