Snow levels in the mountains of southwestern B.C. are exceptionally low.
And while that’s halted skiing at some hills, it may also mean trouble in the months ahead for local water users and migrating salmon.
The B.C. River Forecast Centre’s latest snow survey shows the Lower Fraser watershed has a snowpack of just 45 per cent of the long-term average and Vancouver Island is even lower at just 15 per cent of normal.
“These are very low for this time of year,” said River Forecast Centre hydrologist Tobi Gardner.
He said the warm winter in the Lower Mainland and some very wet winter storms, followed by a mostly dry and mild February, have conspired to melt much of the lower and mid-elevation snow.
Some specific sampling locations are in record low territory.
Jump Creek, between Nanaimo and Port Alberni on the spine of Vancouver Island, measured no snow at all in the latest snow survey – the first zero reading at this time of year since 1966.
Within the Lower Fraser, Spuzzum Creek at 20 per cent, Wahleach Lake at 26 per cent and the Chilliwack River at 44 per cent are all at or near record low readings. (See charts below.)
— Dan Fletcher (@dan_f_fletcher) February 21, 2015
Metro Vancouver officials say it’s too soon to predict if a lack of snow will force unusual watering restrictions come June as a conservation measure.
Reservoirs that supply the Metro drinking water system are typically fed not just by melting snow but also significant amounts of rain.
Gardner said there’s potential for low river flow conditions in many areas that could hinder returning salmon and affect other species dependent on aquatic habitat.
As for the potential for flooding of the Fraser in the Lower Mainland, he said it’s too soon to say.
“The flood risk is certainly not increased but I think it’s too early to say there is not a threat.”
That’s because 85 per cent of the volume in the Fraser at Mission during the freshet comes from snow melting hundreds of kilometres away in the mid- and upper Fraser watersheds, both of which are close to normal snowpack levels.
“That whole snowpack has to come out as well,” Gardner said, noting several days of hot spring weather could melt the northern snow fast.
There’s still time for more snow to accumulate in the mountains between now and April when snow levels typically peak.
But Gardner said it appears continued warm weather may result in the runoff of the snowpack from the upper elevations about a month earlier than usual, in late April and May.
Jump Creek (south Vancouver Island)
Wolf River (mid Vancouver Island)