Snowpack assessments for early April reveal lower levels for northwestern British Columbia and the Burns Lake region.
The Skeena-Nass basin – comprising Houston, Smithers and Terrace – is at 72 per cent, down from 82 per cent in March.
The Upper Fraser West basin, which includes Burns Lake, Fort St. James and Vanderhoof, has a snowpack level of 94 per cent of normal, according to the April 1 data from the BC River Forecast Centre.
The level was 106 per cent of normal for March.
The neighbouring basin of Nechako – in areas including Tahtsa Lake, Skins Lake and Mount Pondosy – is at 72 per cent of the normal snowpack level. It was at 79 per cent of normal in March.
March was very dry across B.C. and the 94 per cent snowpack level for Upper Fraser West was the highest in the province. The lowest recorded level was in the Northwest basin – bordering Alaska and the Yukon – at 47 per cent of normal.
The decrease of snowpack levels from March to April isn’t normal, as Dave Campbell, head of BC River Forecast Centre explained to Black Press.
”We start to see the shift between April and May. Normally we should see [levels] stay the same. The declining number shows that there wasn’t enough snow accumulated already,” he said.
In some years the snowpack levels increase from March to April, such as in 2012 when it went from 144 per cent above normal in the Upper Fraser West basin to 152; in 2013 when it increased from 103 to 119; and last year when it rose from 138 to 145 per cent above normal.
The lower levels across the province for April imply decreased flood risk during the spring snow and ice melt, or freshet season.
“With a lower snowpack, the flood risk is lower, so rain becomes a a big factor in possible floods,” Campbell said.
“We’re seeing the melt start now at lower elevations. Lower snowpacks lend themselves to more prolonged, lower flow of snowmelt. We’re expecting with the temperature forecasts it will be an earlier melt. Some of this melt is happening early and potentially extremely early. We’re kind of bracing ourselves for an earlier freshet season over the next month, instead of in May or June which is more normal.”
Environment Canada forecasts show that temperature levels for most of B.C. have a probability of being 80 per cent above normal for the April-June period.
The April snowpack level for the Upper Fraser West region is considerably lower than for April of 2018 when it was 145 per cent above normal.
Further into April last year the level went higher, leading to floods in the Houston area during the snowmelt.
Two years ago it was significantly lower, at 66 per cent in March and 85 per cent in April.