While the combination of high snowpack, warm weather and a heavy rainfall has led to a worst-case flooding scenario in the B.C. interior, the Lower Mainland is left waiting to see just how high the Fraser River will get.
And the head of the B.C. River Forecast Centre said Friday recent extreme weather has driven rivers up “much, much earlier than normal.”
David Campbell said while the hot weather with rain increases the risks, temperature alone is a concern.
“Hot is in and of itself concerning over the next seven days as water is rising throughout the region making its way down into the Fraser River system, which rises fairly rapidly from headwater down to the Lower Mainland,” Campbell said in a conference call Friday.
Campbell said the Mission gauge – the measure used by most communities to monitor river levels – was at five metres on Friday. The 5.5-metre mark signals “bank full conditions,” and Campbell said that should be surpassed by the long weekend, pushing to the six- to 6.5-metre range by late next week.
By Friday, the river at Hope was running at about 9,000 cubic metres per second (m3/s), a rate that should surpass 10,000 m3/s by the weekend and hit 12,000 m3/s by the end of next week.
The provincial government said Thursday it is encouraging local governments and First Nations communities along the lower Fraser River to prepare for potential flooding,
“The lower Fraser has not seen this combination of weather conditions – including high temperatures, snow melt and riverflow – for a number of years,” according to the Ministry of Public Safety and Solicitor General.
An evacuation alert was issued by the City of Chilliwack on Wednesday for six properties at Carey Point, an area outside the city’s dike system.
The City said the move was precautionary, noting that conditions can change rapidly during the spring freshet. Residents in the alert area are being contacted by city officials.
The City is recommending they be prepared to leave the area on short notice, and director of engineering David Blain said Friday the residents have been provided with sandbags.
As some communities, such as Grand Forks, are experiencing extreme flooding, some people have evoked the massive flood of 1948, which devastated Chilliwack.
Blain said, however, that not only is that level of water not forecast to come down the Fraser, but the city’s diking infrastructure has greatly improved in the 70 years since then.
While even record flows should not affect the city, it’s the areas outside the dike system that are at most risk. Even there, most of the homes should be high enough, according to Blain. Carey Point is certainly at risk, but the 20-or-so homes north of Minter Country Garden on the west side of Young Road have remained unaffected even at the highest water levels in the last 50 years.
Blain said those homes are built high enough that they were unaffected in 2012, and even when the Mission gauge hit seven metres in 1972, those homes remained dry.
The river level is a dynamic situation with many factors playing into it. Continue to visit www.theprogress.com for updates on the water levels on the Fraser River.