The Capital Regional District (CRD) is advising visitors that a blue-green algae bloom has occurred at Lower Thetis Lake in Thetis Lake Regional Park.
This algae produces a visible blue-green sheen on the surface of the water, appearing as surface scum.
However, not all blooms are easy to see and can be unpredictable, occurring at any time.
As a result, the CRD advises visitors to the park to avoid swimming in Lower Thetis Lake and to keep animals from drinking or swimming in the lake until the advisory has been lifted.
Ingesting water containing the toxins present in this algae can cause headaches and abdominal pains in humans and can lead to lethal liver damage in dogs.