
The POA and Elsinore Valley Municipal Water District (EVMWD) took water samples from Happy Camp, Sierra Park, Indian Beach, and Sunset Beach. Lake Elsinore and San Jacinto Watersheds Authority (LESJWA) performed additional testing.
Test results show that all five areas tested on June 16 showed slightly elevated levels of microcystins and are at the caution level. Emerald Cove, located in the East Bay off Emerald Park on Gray Fox Drive, has been raised to a warning level due to testing performed by LESJWA on June 26.
Microcystins are toxins produced by cyanobacteria. Cyanobacteria are also known as blue-green algae and are ubiquitous in surface water when conditions are favorable for growth and formation of algal blooms.
Yellow caution signs are posted around Canyon Lake advising residents to use caution around all forms of algae. These signs remain posted year-round unless testing indicates higher levels of cyanobacteria, at which point orange or red signs are posted as appropriate. Orange warning level signs have been posted at and near Emerald Cove. All other areas tested remain at the yellow caution level.
Some general best practices guidelines regardless of any elevated test include:
- Do not drink the water and try not to get water in your mouth
- Do not eat algae or aquatic plants
- Do not let pets enter the water (they are not allowed in the water by regulation)
- Do not go swimming if you have open wounds or cuts
- Shower after using the lake



Humans who drink or swim in water that contains high concentrations of cyanobacteria or cyanobacterial toxins may experience gastroenteritis, skin irritation, and allergic responses. In conjunction with the State Water Board and the Department of Water Resources, three levels of color-coded advisories have been established so visitors can be informed about the current water condition in a particular area.
- First Level (Yellow Caution Signs): A caution warning indicates that you can swim in the water but you should avoid contact with algae and keep children away from algae. Do not drink the water or use it for cooking. Do not eat shellfish. Do not allow pets to enter the water. This condition is present in a number of areas around the lake.
- Second Level (Orange Warning Signs): A warning means that you should not swim. Stay away from scum or algae, do not drink or use water for cooking. Do not eat shellfish. Do not allow pets to enter the water. This condition is present at Emerald Cove.
- Third Level (Red Danger Signs): Stay out of the water including wading. Stay away from scum or algae, do not drink or use water for cooking. Do not eat shellfish. Do not allow pets to enter 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, scum, or form 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:
- Do not let pets and livestock 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 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 fish or shellfish from this water.
- 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 additional information about harmful algal blooms, visit the California Department of Public Health or the Centers for Disease Control and Prevention.