It appears that the massive fish kill that saw approximately 84,000 fish from a number of species die in the drought-stricken Cowichan River near Skutz Falls last summer may not be repeated this year.
Brian Houle, environment manager at the Catalyst Crofton mill which owns and operates the weir at Lake Cowichan, said in his latest watershed update released on Aug. 7 that, so far this summer, there have been no reports of dead fish in Cowichan River.
He said the peak of the summer heat is almost over and, in a short time, the weather will likely get cooler with dropping temperatures and longer nights, so issues around lower water levels and high water temperatures related to drought conditions, which many fish stewards and biologists believe is related to the death of the fish last July, should lessen as fall approaches.
Volunteers have also been closely monitoring the river this year to locate any stranded fish to avoid any further large fish kills, and in one instance in April, stranded young fish near the Stoltz Pool area were spotted and the volunteers were soon on scene to help move the emerging fry back to the river’s main stream from the drying creek beds.
Catalyst had to use 20 pumps for more than a month in September and October last year to pump water over the weir to sustain water levels in the river, which was running at a very low rate of approximately 4.5 cubic metres per second at the time of the fish kill.
That led to a new approach to managing water inventory in Cowichan Lake this year, and both provincial and federal fisheries aligned on what actions were needed.
It was decided that a slower flow of water over the weir of about 15 cubic metres per second, much lower than in previous years, during the spring months would be implemented to keep more water in the lake that could be used to keep water levels in the river higher without having to use pumps during this summer would be the target until June 15 when a seven cms river flow kicked in.
“We are now at a stable 7.08 cms being released into the river from the lake,” Houle said on Aug. 7.
