Due to the ongoing dry conditions as of May 7, water levels in Cowichan Lake were significantly less than what they were this time last year.
Brian Houle, the environment manager at the Catalyst Crofton mill which owns and operates the weir at Lake Cowichan, said that on May 7 last year, the lake was 90 per cent full, but it鈥檚 down to 74 per cent this year.
He said the snow pack in the surrounding mountains that feed the lake with water in the spring months is below average this year.
鈥淚n response to the watershed conditions, Domtar (which owns the Crofton mill) has been guided by the regulators of the watershed to begin to reduce the river flow from Cowichan Lake as soon as possible, but with the condition of having stewardship in the [Cowichan River] to support the flow reductions from ideal spring flows,鈥� Houle said.
鈥淏eginning [May 8], and with environmental professionals hired to monitor conditions in the river, flow [from the lake into the Cowichan River] will be reduced by one centimetre [to 14 centimetres].鈥�
Houle said the plan is to continue to decrease the water flows from the lake by one centimetre a day until May 12 when it reaches 10 cms., and hold it there for the time being until conditions are further assessed. The aim is to retain more water in the lake for the dry summer season.
鈥淎 special meeting, which will include the regulators engaged in the Cowichan watershed management program, is scheduled for May 12 and will include a review of current watershed conditions and then provide Catalyst with the authorization to take the needed action of flow reductions to secure the watershed for 2025,鈥� he said.
鈥淚deally, a flow of 15 cms. would be sustained to June 15 and for 2025. It appears a lower flow will be needed to support a full lake level as we enter the dry season,鈥� Houle said.
The severe drought that struck the region in the summer of 2023 lowered water levels in Cowichan Lake and the Cowichan River dramatically, and resulted in the deaths of approximately 84,000 fish in the river.
Catalyst had to use 20 pumps for more than a month in September and October of that year to pump water over the weir to sustain water levels in the river.
That led to a new approach to managing water inventory in Cowichan Lake, and both provincial and federal fisheries are now aligned on what actions are needed as the dry season of 2025 approaches.
Maintenance of water levels in the lake and river were deemed a success during the 2024 dry season, when the lake level supported seven cms. flows out of the lake all summer, with no evident fish kills in the Cowichan River and no need for pumps in the fall.
