Rock Slide on Sea to Sky Highway
The Issue
• Route 99 is the only direct route between Vancouver and Whistler in the North
• In July 2008 an estimated 16,000 cubic metres of rock fell on to the highway
• This led to a five day closure with thousands affected
• There are now major concerns about a re-occurrence during the 2010 Winter Olympic Games
Rock Slide on Sea to Sky Highway
Geology
• A geologically active region in steep mountainous terrain
• The bedrock along the route consists of highly fractured argillite and volcaniclastic rock
• The joints within the rock are at approximately 45 degrees
• The highway undercuts the rock structure meaning near vertical cliff faces along portions of the road
Rock Slide on Sea to Sky Highway
Short Term Solution
• Re-opening of the highway was the top priority
• The newly exposed slope stability was assessed
• Loose rock from above was removed by rock scalers
• Plant at either end of the site used to transport the rubble away
Rock Slide on Sea to Sky Highway
Long Term Solution
• The future stability of the rock face along the highway needs to be ensured
• $775 million is being spent on upgrades to the Sea to Sky Highway and its surrounding rock structures
• To help prevent future slides pre-emptive blasting, rock scaling and rock bolting are being carried out
• The highway itself is undergoing widening
• There are calls for the construction of an additional route between Vancouver and Whistler