Dry conditions in the Campbell River watershed are forcing BC Hydro to move water levels to summer conditions a month early.
Despite the month of April having higher than normal precipitation BC Hydro is having to closely monitor the Campbell River system. This includes not just managing through the summer, but looking ahead to the fall and the salmon migration and spawning period. Communication and coordination with the Department of Fisheries and Oceans Canada remains a key part of our potential operations through October, BC hydro said in a press release..
BC Hydro spokesperson Stephen Watson said precipitation has been sparse since February with the exception of April. February was 30 per cent of normal, March 18 per cent of normal, and April was 137 per cent of normal. For perspective, though, the April monthly average rainfall is about 64 per cent of the March monthly rainfall. The February to May period in 2018 was also dry. So far, May is off to a dry start at just 3 per cent of average.
After essentially staying the same for about 2.5 months, the snowpack briefly increased and peaked in April, and is now melting with the warm weather. The snowpack is lower than normal.
BC Hydro’s February to September water supply forecast is updated each month. Its updated May water supply forecast for the period of February to September is showing 62 per cent of normal. The residual forecast for water inflow from May to September is 63 per cent of normal.
Since March 25, BC Hydro has held the Campbell River at about 69 cubic metres per second (m3/s). This is below the preferred level of 80 m3/s that keeps the riverbed fully covered with water.
“With the dry water supply forecast as we head into the summer, we have been in communication with DFO around the progress with and timing of this spring’s salmon fry emergence and outmigration,” Watson said. “We may then potentially drop the river flow down to about 30 m3/s as early as late May to conserve water within the upstream reservoirs.
“This approach serves a few purposes. First, in the near term, it may bump up the already very low reservoir levels and benefit summer recreation users. Second, for the returning fall salmon, it will save a bit of water over the summer and have a little more storage to increase river flows in October for salmon migration and spawning.”
Water inflows into the Campbell River system have come up considerably this week, forecasted to peak over 100 m3/s, with snowmelt occurring at all elevations due to the warm weather.
When BC Hydro slowly lowers the river flow as early as late May, it will have biologists on the river to move fish that may get isolated back into the Campbell River mainstem.
“In the summer there is generally little rain. This is why we are moving the river flow into a much lower flow rate given the situation for summer recreation activities in the Upper Campbell Reservoir/Butte Lake and Lower Campbell Reservoir/McIvor Lake, and for salmon in the fall,” Watson said. “Typically, around July 1 we begin reducing the Campbell River to its summer flow rate, which can be as low as 30 m3/s. In some years this reduction has begun in June. This would be the first time since the Interim Flow Management Strategy operation regime that started in the late 1990s, and the water use planning regime more recently, that we look to lower that flow rate to 30 m3/s within the month of May.”
The water levels in Upper Campbell Reservoir and Butte Lake are currently at about 214.1 metres and 214.35 metres, and are slowly rising. The reservoir and lake separate at these low levels. This current level is just over three metres below the last six years’ average for this time of year. The summer recreation target from mid-June to early September is 217 m to 220.5 m. BC Hydro forecasts, despite these efforts to further conserve water, and unless there is a significant change in the weather, that the reservoir level may only hit a high of about 215.8 metres early this summer before slowly drifting downward.
The Lower Campbell Reservoir/McIvor Lake is currently at about 176 metres. The current forecast has the reservoir level slowly decreasing to about 175.5 metres in the summer, well below the summer target. The target for this reservoir’s summer recreation level is 176.5 metres to 177.5 metres.
For the Quinsam River, BC Hydro’s water licence minimum river flow rate lowers from 2 m3/s to 1 m3/s on May 1.
“We look to maintain the 1 m3/s flow rate and that should help the water storage in the upstream Wokas Lake, and ultimately, the storage as we move through the summer and early fall,” Watson said.
BC Hydro may provide a water supply and operations update in June.
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