City of Chilliwack is advising residents to be extra cautious around any fast-moving water in the area.
The provincial River Forecast Centre issued a flood watch for the entire region on Monday (Dec. 4), including the Fraser Valley, Lower Mainland, and Whistler regions.
“Heavy rains can cause local rivers to rise and move quickly,” according to the city’s flood watch webpage. “Please use caution around fast-flowing waterways.”
The flood-watch forecast issued for the Chilliwack/Vedder River system on Dec. 4 predicts flows will be in the range of 300 to 400 cubic metres per second. That equates to about a 1:2 return period, which is not considered unusual for heavy rainfall events of late fall and winter.
Floods occur in rivers when the flow rate exceeds capacity of a river channel.
“The dikes are designed to protect against much larger flows. The city will continue to monitor conditions and forecasts,” the notice said.
When is a “flood watch” issued? The River Forecast Centre issues it when “river levels are rising and expected to approach or exceed bankfull” conditions.
Sometimes flooding adjacent to affected rivers may occur. Here’s how to stay safe around rising water.
Heavy rainfall can cause localized pooling or ponding so Chilliwack residents are asked to ensure nearby storm drains and catchbasins are clear of any debris.
To report localized flooding, go through the City of Chilliwack app, or by calling the Operations Department at 604-793-2810.
Sandbags and sand for filling are available in Townsend Park in the west, gravel parking lot, for those interested they’re asked to bring their own shovels.