Canadian Consulting Engineer

Feature

Transportation: Klemtu Access Road

The village of Klemtu is located on Swindle Island, 220 kilometres north of Port Hardy on B.C.’s spectacular interior coast. The community is home to 500 people in the Kitasoo and Xaixais First Nation, whose only access to the outside...


Aerial view of Klemtu including access road to ferry terminal.
Aerial view of Klemtu including access road to ferry terminal.

The village of Klemtu is located on Swindle Island, 220 kilometres north of Port Hardy on B.C.’s spectacular interior coast. The community is home to 500 people in the Kitasoo and Xaixais First Nation, whose only access to the outside world is by air and water.

Only one ferry a week visited the village until a new terminal and docking facilities were completed in 2011. McElhanney engineered the new ferry terminal which allows BC Ferries to send larger vessels to Klemtu, thus improving its economic prospects, allowing for easier transportation of goods, people, and hopefully increasing its eco-tourism trade.

The biggest technical challenge was building the two-kilometre access road between the terminal and the village. The road follows an existing pathway through steep rainforest adjacent to the Pacific Ocean, crosses numerous creeks and is in an environmentally sensitive corridor and fish habitat. The area has extremely heavy rainfall, so good drainage and erosion control were critical. The road is used not just by the ferry passengers, but also by commercial traffic from the local fish processing plant, so it has a design speed of 50 km/hour.

Because the project was partly funded under Canada’s Economic Action Plan, the design and construction had to be done within four months. This short time frame, together with the site’s remoteness, meant it was not feasible to do ground survey and geotechnical investigations. Instead, McElhanney designed the road using orthophotographic imagery and LiDAR data, with provision for minor design changes on site.

It was neither economic nor practical to process asphalt for the paving on site, so McElhanney worked with the Ministry of Transportation and Infrastructure and the contractor to develop a special mid-temperature asphalt that could be mixed hundreds of kilometres away in Kitimat and transported to Klemtu without cooling and hardening. It took 18 hours to ship the asphalt mix by barge, and then eight hours to offload it. Two trips were necessary.

The asphalt looks and behaves similarly to regular asphalt but incorporates a special additive and is prepared at a slightly lower temperature. Normal hot-mix asphalt is about 170 to 180o C, whereas this “warm mix” was loaded at around 148-150o C, and compacted at 128-130o C. The asphalt (50-mm) was laid over a standard road structure, but with an intermediate graded base course using materials from a rock quarry on site. McElhanney provided quality assurance testing for the road materials.

The entire paving process was done within a three-day window. Any errors would have resulted in wasted pavement at a cost of over $1 million.

About 150 local people were employed on the overall project. Rain fell for more than 80% of the construction days, and in one eight-day period 1100-mm of rain fell. The team worked through gale-force winds and a tsunami warning that forced everyone to abandon site and hike two hours through deep snow up a mountain to reach safe ground.

Despite the inclement weather, the work was completed in the four-month schedule and $4 million below the $25 million budget.

cce

Client-Owner:

B.C. Ministry of
Transportation & Infrastructure

Prime consultant/project manager:
S

NC-Lavalin

Engineer-of-record, terminal and
access road:

McElhanney Consulting
Services, Campbell River, Surrey,
Vancouver (Mark DeGagné, P.Eng.,
Santino Piriloo, P.Eng., Joe Vorlicek, Tavis McMullen, Don Hounsell)

Other key players:

GeoNorth Engineering (asphalt mix design); Bear Creek Contracting (general contractor), Terrace Paving (asphalt sub-contractor).