Cool weather is creating a significant delay in the snow melt and causing headaches for BC Hydro as it tries to control water levels.
The snow pack historically peaks at this time of year and then begins to slowly melt until depleted around the end of June. But with cooler temperatures this year that’s not happening.
Hydro received permission in February from the Comptroller of Water Rights to exceed its water licence, and operate the John Hart Generating Station at full capacity all summer long, to help draw the reservoir down in anticipation of a high snow melt runoff.
However, with the delay in snow melt, Hydro has been forced to decrease the power generation to about 80 per cent in consideration of low reservoir levels.
“An already unusual year has become more challenging as BC Hydro considers reservoir and river interests through mid-September,” said Stephen Watson, spokesperson for BC Hydro.
“Upper Campbell Reservoir/Buttle Lake is likely to remain lower than normal through June.”
The Upper Campbell/Buttle Lake Reservoir hit a low of 213.2 metres on May 11, but since then the level has been steadily increasing and is currently at 215.1 metres.
“BC Hydro operations modelling, with considerable uncertainties due to future temperatures and rain, shows the reservoir hitting ideal recreation levels of 218.5 m and above by mid-July,” said Watson.
The model also shows the reservoir may hit a peak of around 220 m by late August, which is considered full.
The Lower Campbell Reservoir levels will track in a similar fashion.
Typically, BC Hydro attempts to target ideal recreation levels in June but this year it will be unable to do so due to the amount of snow melt still to come.
“The concern is the reservoir would get too high in August during a time when there are fish and recreation impacts if flows are too high below John Hart,” said Watson, who added there is no downstream flood risk.
The Upper Wolf River weather station, towards Campbell River, is showing a snow melt to water equivalent of about 2,137 millimetres.
This is about 190 per cent above normal for this time of year and the second largest on record.
BC Hydro will likely continue to operate John Hart at 80 per cent of capacity, potentially increasing to full capacity during the peak snow melt, through to July 4.
It will then operate at 80 per cent of capacity.