Flood warning for Sumas River downgraded to ‘watch’

B.C.’s River Forecast Centre has downgraded a flood warning for the Sumas River to a flood watch, as a series of storms continues to drench the province’s South Coast.

The centre says the river levels along the Sumas River in Abbotsford are expected to experience “periods of high flows into next week,” however widespread flooding is not expected beyond what has been seen in localized areas along the Canada-U.S. border at the Nooksack River in Washington State.

“Additional hazards for overflow from the Nooksack may be present from the incoming storm systems on Monday through Thursday, however hydrologic modelling from the Northwest River Forecast Center with the US National Weather Service is not forecasting this scenario,” read a Sunday night alert from the BC River Forecast Centre.

A flood watch is being maintained for all of BC’s South Coast, including Howe Sound, Sunshine, Coast, Sea-to-Sky, and North Shore Mountains, as well as the Fraser Valley (affecting tributaries from Port Coquitlam to Harrison), as well as Vancouver Island.

The provincial government has been funding and working on mitigation measures in the Fraser Valley since the catastrophic flooding of the Sumas Prairie in November 2021 caused billions of dollars in damage.

B.C. and Washington have also agreed to jointly address Nooksack River flooding along the border, however, there is still no timeline for any of that work and the agreement is not legally binding.

In an interview with CityNews in October, Premier David Eby indicated at that time that talks are ongoing.

“There are several talks ongoing with Washington State right now. The Columbia River treaty is one of them, as well as the Nooksack River and how we mitigate flooding in that area of Abbotsford,” he said.

A high streamflow advisory remains in place for Lower Fraser River tributaries including areas around Pemberton and Lillooet River tributaries, Fraser Valley – East, and Fraser Canyon.

The centre says the strongest system is expected to arrive Monday and persist throughout the region until the middle of the week.

It says the heaviest rainfall will hit western Vancouver Island and the Coast Mountains, with between 200 and 400 millimetres in the forecast.

Listen live to CityNews 1130 for any further information about flood warnings across the South Coast. Listen live every 10 minutes on the ones for weather updates. You can also follow us on X @CityNewsVAN and subscribe to breaking news alerts sent directly to your inbox.