July could see a very grim situation for fish survival in Cowichan Lake’s tributaries and Cowichan River due to low water levels, according to Bob Crandall, the Ts’uubaa-asatx fisheries director with the Cowichan Lake Salmonid Enhancement Society & Hatchery.
Crandall said he expects as the dry summer weather kicks in this year, society members will be hard at work rescuing tens of thousands of salmon and trout juveniles from drying pools in the tributaries of Cowichan Lake, while other teams do the same work downstream in Cowichan River.
Brian Houle, environment manager at the Crofton mill, which owns and operates the weir at Lake Cowichan, said recently that this summer season is now becoming as challenging as 2023 when a severe drought lowered water levels in Cowichan Lake and the Cowichan River dramatically, which resulted in the deaths of approximately 84,000 fish in the river.
As of July 7, Cowichan Lake was just 48 per cent full and now that the summer’s hot and dry weather has arrived, water levels are expected to continue to drop, and water flows from the lake into the river over the weir are expected to be lowered soon to keep more water in the lake, which means even less water going into the river.
Crandall said the fact that the water levels in the lake have dropped so much so early in the season is deeply concerning for fish survival in the lake’s tributaries and Cowichan River.
“We have great concerns for the fish in our watershed and we are trying to bring to light the depth of concern...literally,” he said.
Crandall said that on July 8, the society’s teams moved more than 1,000 fish from increasingly dry Cowichan Lake tributaries to deeper water, and that work is expected to become more important in efforts to prevent a major fish kill during the summer months if the dry conditions continue.
“We move the fish from the drying pools to the closest release point in deeper water, but there are some storage pools in the tributaries that are spring fed and usually 18 feet deep that are now only four feet deep,” he said.
“Having the water levels so low is terrifying for our efforts to save the fish, but we will continue our work and hope water levels won’t go much lower.”
Crandall said the society isn’t encouraging people who spot isolated fish in drying pools and aren’t trained to try to move them to deeper water.
He said not only is he concerned that they may injure themselves on unstable river beds, but they don’t have the knowledge needed for proper fish transfers.
“People need to know what they are doing because moving the fish from one body of water to another where the temperature of the water is different may kill them,” Crandall said.
He said there are also concerns about water quality in the Cowichan River as water levels drop.
There is sewage outfall, that is treated, from Lake Cowichan that enters the river and if the water levels get too low, it will impact the dilution of the outflow that would negatively impact the water quality.
