It’s safe to swim at Elk/Beaver Lake Regional Park, following the CRD’s lift on its two-and-a-half month blue-green algae advisory.
The district announced the end of the advisory on Friday after samples collected from the Beaver, Eagle and Hamsterly Beaches indicated a “below detection limit” result for microcystins, a class of toxins produced by certain freshwater cyanobacteria.
The temporary advisory was issued on Dec. 23 when the district first noticed a bloom of algae on the lake. Algae blooms are unpredictable, and ingesting water containing blue-green algae is known to cause a range of symptoms, including headaches and abdominal pain in humans, and can lead to lethal liver damage in dogs.
“The blue-green algae bloom is pretty obvious – it’s an iridescent blue-green sheen on the surface of the water, and so it’s quite visible and it gets everyone’s attention,” said Glenn Harris, senior manager of the environmental protection division with the CRD.
“Very conservatively, we assumed that this algae was producing potential toxins in the water. Signs went up, and as long as we could see the bloom at some point around the lake, we just made the assumption that it was present in toxins.”
Thetis Lake had blue-green algae earlier this year and the mild winter lent to the Elk Lake bloom lasting a bit longer than usual.
The Vancouver Island Health Authority currently has advisories posted for elevated bacteria concentrations in Cadboro Bay and Cordova Bay.
They are believed to be related to stormwater discharges and some creek overflows, Harris said.
“You get these heavy rains that overflow the stormwater pipes and you get elevated fecal concentrations, enough to exceed the limits.”
Sightings of lake algae can be reported to the CRD at firstname.lastname@example.org or by phone at 250-478-3344.