Warming weather is causing rivers to rise in northern British Columbia, prompting the province to encourage people to prepare for possible flooding.
A joint statement from the Ministry of Public Safety and Emergency Management B.C. says a warming trend this week is pushing temperatures to the highest yet this season and there’s a possibility of moderate to heavy rainfall this weekend.
The province says the risk of flooding is elevated in parts of the Interior and northern B.C., where cooler-than-normal temperatures have delayed snowmelt.
The forecast has also spurred one community to activate its emergency operations centre in anticipation of possible flooding.
The City of Terrace says on its website that activating the centre allows officials to begin flood preparations, but it does not mean a local state of emergency has been declared.
Terrace is on the edge of a broad area in northern B.C. covered by a high streamflow advisory that the River Forecast Centre issued on Wednesday.
The advisory warns that water levels are climbing in the Liard, Skeena and Stikine rivers and their tributaries, and minor flooding in low-lying areas could occur.
The centre says snowmelt rates and river runoff are increasing due to warming this week and temperatures were expected to top 20 C in valley bottoms Wednesday.
It says more unsettled weather is expected Thursday and into the weekend with potential rainfall adding to the swell of rivers.
Modelling suggests the flooding may occur this weekend, and the advisory may be upgraded to a more serious warning depending on the weather and how the rivers respond, it says.
“The public is advised to stay clear of the fast-flowing rivers and potentially unstable riverbanks during the high-streamflow period,” the advisory says. “Be prepared and know your hazards.”
The City of Terrace says the River Forecast Centre shows the Skeena River could reach levels by Sunday that are recorded only once in a century.
In anticipation of high water, the city is closing the boat launch at Fisherman’s Memorial Park and the 60-hectare Ferry Island Park and municipal campground by Friday, or earlier if conditions worsen.
It says it expects to release more details about where residents can collect sandbags to protect their properties.
The latest survey of B.C. and Yukon snowpacks shows many are at levels not seen in a decade, as cool, wet weather delays snowmelt, increasing the chance of flooding if a long period of warm weather occurs, but there is no sign of a long heat wave in the River Forecast Centre’s predictions.
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