High snow levels have raised the risk of spring flooding in the Skeena-Nass region, but actual chances of a Houston flood depend mostly on what weather comes in May and June.
B.C.’s River Forecast Centre reported the elevated regional flood risk in its latest snow bulletin, which is based on snowpack data collected up to early March.
By this time of year, more than 80 per cent of the B.C.’s snowpack has already built up.
Snow pillows at Lu Lake and Tahtsa Lake, which both feed Houston waterways, showed levels at 132 and 151 per cent above normal last week, with the Tahtsa Lake levels nearing a 19-year record.
“We have a pretty good idea of the snowpack at this point,” says RFC manager Wenda Mason.
With just a month to six weeks of snowpack potential, Mason said more than 80 per cent of B.C.’s snowpack hits is accounted for.
In a typical flood year, Houston residents are likely to see Buck Creek and the Bulkley River rise to flood levels first, with the Morice River peaking soon after.
But although high snowpack raises flood risk, Mason said the key to a freshet—or spring river rise—is what weather comes during the May and June snowmelt.
“Last year we had the freshet that went forever,” she said, adding that although B.C. had a high snowpack last year, it also had cooler than expected weather in the melt season.
“We were working constantly through May to the first half of July, where normally we’re done freshet by the first half of June,” she said.
Fire Chief Jim Daigneault, who coordinates Houston’s response to floods and other major emergencies, said the District is well prepared should flooding occur.
Houston’s dikes have been raised since last spring, he said, and a new pump station installed last year is ready to go.
Predicting weather is notoriously tricky, but the RFC’s March bulletin does point to one broad trend—more precipitation than usual in this La Nina year.
Mason said the RFC’s next bulletin, due in mid April, is the one that will prompt any necessary talks with local governments and emergency service coordinators.
Houston Fire Chief Jim Daigneault said the District is well prepared for snowmelt season this year, having raised the dikes outside town.
For the latest information on B.C. river levels, visit bcrfc.env.gov.bc.ca.