August 11, 2008

B.C. MINISTRY OF TRANSPORTATION

A massive landslide on July 29 stopped vehicle and rail traffic in both directions on the Sea-to-Sky Highway for four days. Crews worked around the clock to clear the debris.

Road crews work ’round the clock to clear Sea-to-Sky Highway ahead of schedule

RICHARD GILBERT

staff writer

British Columbia’s Sea-to-Sky Highway reopened ahead of schedule, after clean-up crews worked around the clock to clear debris and get traffic moving.

A huge landslide left a massive pile of rock and debris just north of Porteau Cove on July 29, burying a nearby railway line and two lanes of Highway 99 that connect Vancouver with Squamish and Whistler.

British Columbia Transportation and Infrastructure Minister Kevin Falcon announced on Aug. 2 that Highway 99 had reopened to all traffic.

Traffic flowed freely for the remainder of the holiday long weekend.

“No one knew exactly how long it would take to knock those big boulders down to size,” said Dave Crebo, communications director with the Ministry of Transportation.

“The crew worked all night long and made great progress by Saturday, so the opening was moved up to Sunday. They kept at it all day Saturday and by 4:30 pm all the debris had been cleaned up.”

Once the debris had been cleared, the crews were able to assess the damage to the road.

“There was significant damage for a 100-metre stretch of road,” Crebo explained.

“The repairs started immediately. The crews were able to fix the damage with gravel and asphalt they had already brought in.”

Originally, it was estimated that it would take five days to remove the debris and reopen the road.

An important factor behind the faster clean-up was a decision by the Department of Fisheries and Oceans (DFO) on July 30 to allowed debris to be dumped into nearby Howe Sound.

“When the DFO gave permission, it really sped up the removal of the debris,” said Crebo. “Otherwise it would have had to be trucked out.”

The first phase of the cleanup process involved rock climbers and engineers, who worked together to assess the stability of the cliff face. The rock climbers also removed loose rock from the cliff above the highway.

Falcon said on July 30 that a section of rock overhanging the two-lane highway needed to come down before crews could safely move in to clear the estimated 16,000 cubic metres of rock and debris.

Crews started drilling and blasting the dangerous rock overhang.

The blasting crew arrived at the rock slide early in the morning on a boat loaded with equipment.

Crew members drilled holes in the rock overhang, plugged in dynamite and gave a two-minute warning before triggering the explosives.

Inspections were undertaken on Aug. 1 to determine if more blasting was needed.

“After the blasting was done, the crews assessed how successful it was. The whole point of blasting was to get the dangerous stuff down and make the whole site safe for workers to go in and start the work of cleaning up,” said Crebo.

When the rock overhang was stable, scalers hanging from ropes used crowbars to pry away loose material, while heavy equipment was used to push the debris off the side of the road and into the ocean.

The cause of the rock slide has not yet been determined, but geotechnical engineers believe a long period of hot, dry weather followed by a few days of rain triggered the natural disaster.

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