A beautiful but treacherous stretch of two-lane highway in the eastern forests of British Columbia has been smoothed out thanks to innovative solutions for building four bridges, nine viaducts and seven earthwalls on steep slopes. The $331-million contract to realign and upgrade a 4.8-kilometer section of Trans-Canada Highway 1 to four lanes from two eliminated 13 hairpin curves and protected motorists from rockfalls and avalanches.

Detailed geotechnical drilling led to significant design changes from the pre-award concept, including replacing earthwalls with viaducts. “The original thinking was to do many more walls,” says Michael Lorimer, vice president of major road, bridge and tunnel projects with the Transportation Investment Corp., a provincial entity. “At end of the day, the team came up with a design that was repeatable throughout the job. We ended up with a better long-term product.”