Blue-Green Algae Bloom

Oct 16, 2023 (updated Jan 11, 2024, 9:48am)

There is no longer a visible blue-green algae bloom at Thetis Lake. This advisory remains in effect for Beaver Lake and Elk Lake.

The Capital Regional District (CRD) advises, in consultation with Island Health, that there is no longer a blue-green algae bloom at Thetis Lake, located in Thetis Lake Regional Park. The advisory remains in effect for Beaver Lake and Elk Lake, located in Elk/Beaver Lake Regional Park. Blue-green algae can produce cyanotoxins. Visitors are advised to avoid contact with blue green algae and to keep animals on a leash to prevent them from drinking or swimming in the lake until the advisory has been lifted.

The algae usually produce a visible blue-green sheen, which appears as surface scum on the water. Not all blooms are easy to see and toxins can still be present in the water even if you cannot see a bloom. Blooms are unpredictable and may occur at any time.

These algae are known toxin producers. Ingesting water containing these cyanotoxins may cause a range of symptoms, including headaches and abdominal pain in humans, and can lead to lethal liver damage in dogs.

Please visit and X @crd_bc for updates on the status of this algae bloom. To learn more about blue-green algae visit these sites: