Thetis Lake algae alert still in effect: CRD

A Blue-green algae bloom is pictured at Prior Lake: (CTV Vancouver Island)

While a heat warning may be in effect for parts of Vancouver Island this week, residents should still avoid a popular swimming hole in the Langford area.

A blue-green algae warning for Lower Thetis Lake and Prior Lake is still in effect, the Capital Regional District said Monday, nearly a month after the warning was first issued.

Blue-green algae is poisonous to humans, and can cause abdominal pain or headaches if ingested.

This type of algae is also harmful to dogs and can potentially lead to lethal liver damage if ingested by pets.

The algae usually produces a blue-green sheen on the surface of the water. However, it's not always visible and blooms can still be present even if they aren't seen.

Residents are encouraged not to swim in either lake and to keep pets on a leash so they don't accidently swim or drink the water.

Park-goers are advised not to enter the water until the CRD lifts the algae alert.