Chilcotin, Fraser rivers settling after B.C. landslide surge

Three days after water and debris from a breached landslide powered down the Chilcotin and Fraser rivers in southwest British Columbia, officials say the surge is starting to settle.

Last Wednesday, a landslide blockedthe Chilcotin Riverat Farwell Ranch, about 285 kilometres north of Vancouver,causing water, fallen trees and other debris to buildinto a rising lake behindthe slide.

Water began spilling over the dam on Monday, and soon carved a channel through the landslide that sent a dangerous torrentrushing down the Chilcotin and into the Fraser River.

In an update Wednesday evening, the province said the pulse of water has "essentially dissipated" into thesouthern reaches of the Fraser River in B.C.'s Lower Mainland.

But Nathan Cullen, the B.C. minister of water, land and resource stewardship,said in a Thursday afternoon update that there's still arisk of downstream impact as water and debris flow to the ocean following the "historic" landslide. He said slope stability remains a concern as small slides have been occurring along the riverbank.

"We're not 100 per centout of the woods justyet, but the main threat is clearly lessened," he said.

The focus now is on assessing fish passage across the Chilcotin landslide site, according to Cullen.

WATCH |Debris from B.C. landslide reaches the Fraser River:

Debris washing into the Fraser River from the Chilcotin River landslide

23 days ago

Duration 0:57

The surge of water that breached a massive landslide blocking the Chilcotin River is moving down the Fraser River into the Lower Mainland, bringing tons of debris with it.CBC rode along with the captain of a water taxi business in Mission to take stock of the crowded waters.

The peak of the surge passed through Hope, B.C.,on Tuesday evening, raising river levels by about 1.1 metres, according to the province. Peak flow passed through Mission, almost 100 kilometres downstream of Hope, on Wednesday morning.

Connie Chapman, executive director of the province's water management branch, said Thursday thatthe flows have returned to normal.

The River Forecast Centre has rescinded all warnings, watches and advisories for the Fraser River.

A flood warning remains in place for the Chilcotin River upstream of the landslide, while a flood watch is still in effect downstream to the confluence with the Fraser.

Chapman estimates there were around 60,000 cubic metres of debris, half of which was captured by the debris trap.

Cullen said this is the equivalent of around 2.5 million dump truck loads of materialentering the river at once. He added that he's not aware of any significant infrastructure issues beyond the natural impact on the river banks.

WATCH | Landside's impact on sockeye salmon:

How the Chilcotin River landslide could affect B.C. salmon runs

23 days ago

Duration 7:51

Jason Hwang from the Pacific Salmon Foundation says the landslide is a "major setback" for fish that have had to endure a lot in recent years, from a landslide at Big Bar to warming water caused by climate change.

While the Cariboo Regional District lifted evacuation orders and alerts forthe area near Churn Creek, evacuation orders remain in place stretching from near Hanceville, B.C. to where the Chilcotin and Fraser rivers meet.

The Big Bar Ferry will remain out of service for about a week due to safety concerns, according to DriveBC.

The province said it will be removing remote cameras near the landslide on Thursday, but it will continue to monitor the situation.