As the final phase of the Kicking Horse Canyon Highway Improvement Project goes forward to a proposal call for the design-build project this fall, it will set new records for expenditures on highway construction and challenge the best and brightest in engineering.
Phase 4 will complete a two-decade effort of upgrades to 26 kilometres of the Trans-Canada Highway that runs between Golden and the Yoho National Park's western B.C. border at a cost of $767 million when complete in 2024. More than half the budget is allocated to Phase 4, which is a four-kilometre stretch of highway. The first phase was completed in 2006.
"This is an area where Mother Nature has thrown a whole bunch of challenges," said Town of Golden Mayor Ron Oszust, but the completion of this stretch will also mean a faster and safer connection to Calgary and reduce travel time to 3.5 hours.
Oszust said the entire 26 kilometres of highway upgrades has been challenging for both construction and engineering. This last stretch, however, holds out greater obstacles as the road is only a ledge in the canyon and runs along the Kicking Horse River with a rail line below.
"It is tight and narrow and the rock is not stable — it would be different if it were granite but it is crumbly," Oszust said, adding at one time a tunnel costing $750 million was proposed but then abandoned as too costly.
The canyon's pass has an elevation of just over a mile. The Trans-Canada Highway, constructed as two-lane access, was pushed through the pass in 1962 following the CPR route and reaches its highest point with an elevation of 5,390 feet.
The three earlier phases have already impacted the number of traffic accidents and fatalities on the highway, Oszust said, as the area is popular with tourists as it bounds five national parks. The town of 4,200 has a motel strip with 3,000 beds.
The B.C. government acknowledges it will be costly and an engineering challenge.
"The four kilometres will cost over $100 million per kilometre," said Murray Tekano, major capital expenditures director for the B.C. Ministry of Transportation. "It is the most expensive highway construction per kilometre done in B.C."
The $450-million project will call for widening the old two-lane highway into a divided four-lane one to match the work on the previous upgrades.
Tekano, who will oversee Phase 4 and was involved in the Phase 2 upgrade, said the cost reflects the challenges of the site.
"It will be a challenge in terms of the engineering approach and how it will be built," he said. "We anticipate some innovative engineering throughout."
Innovative approaches can run the gambit from dry bridges to avoid avalanches to cantilevered structures used to widen the road. The work needed to improve this stretch of the Trans-Canada will include a combination of bridges, retaining walls, rock catchments and other abatement measures to reduce rock fall hazards.
"I am quite excited about it. It is a challenge and we are looking forward to it," he said, as a ministry team is being assembled to determine the design and building specifications that the design-build proponents would have to meet. He said the project would not be a public-private partnership, but those wanting to put forward a proposal would also have to go through a qualifying process first.
Tekano said the ministry would be looking for a fixed-price on the four-kilometre stretch and the budget amount set is $450 million. The schedule is anticipated to see a call for proposals in late 2017 or early 2018, a chosen proponent in 2018 and construction in 2019.
The engineering and construction work already carried out on the Kicking Horse Canyon highway project has left a legacy of new and award-winning innovation.
Phase 2 of the highway project, consisting of 5.8 kilometres, was B.C.'s first design, build, finance, operate highway project with Trans-Park Highway Group, which consisted of Bilfinger Berger BOT, Flatiron Constructors Canada, Parsons Overseas Company of Canada and HMC Services as the builder and operator.
The Trans-Park Highway Group will also operate and maintain the entire 26-kilometre stretch once completed.
One of the Phase 2 award-winning features is the Park Bridge (often called the 10-Mile Bridge).
"It is an amazing feat of engineering and construction," said Oszust. The bridge over Kicking Horse Canyon measures 1,328 feet in length and was the first curved incrementally launched bridge in North America. It is supported by five piers standing 300 feet tall.
Flatiron Constructors used an innovative method of a hydraulic launch system to erect the main steel girders onto the bridge piers. The 410-foot launching bed at a sloped grade launched the girders at one end of the bridge site, one pair at a time, boosting them from pier to pier until all were in place.
As seen in the construction of various phases are sections of the highway, such as Mile 6, that are cantilevered out from the main road bed to provide the needed space for the four lanes.
Techniques such as the girder launch and cantilevered road construction were replicated in other B.C. highway construction such as the Sea-to-Sky Highway and the Port Mann Bridge, Tenako said.
Phase 3 of the work also brought "critter crossings" to the highway. The Kicking Horse Canyon highway upgrade saw four critter crossings installed to allow big-horned sheep to cross.
Tekano expects the innovative proposals will bring not just the completion of what has been one of B.C.'s most challenging highway upgrades but more innovation that will leave a further legacy of engineering and construction.