Highway 1 at Falls Creek was one of many locations severely damaged by flooding during the catastrophic atmospheric river in November 2021. The existing deep-buried culvert at Falls Creek became overwhelmed, leading to overtopping at the highway and a major embankment washout, creating an 80-metre gap and closing the highway. Emergency repairs allowed the highway to reopen with single lane alternating traffic on a temporary bridge, which required escorted vehicle convoys 24/7 at considerable expense and travel delay.

To make permanent repairs, the Ministry of Transportation and Transit (MOTT) chose the Alliance Contract model. Stantec teamed up with the Ministry and contractor Eurovia/BA Blacktop to form the Falls Creek Alliance (FCA), tasked to identify the best permanent solution. After careful evaluation, a 79-metre single-span bridge was selected, and the Alliance worked collaboratively to develop the detailed design, construction plans, and build the crossing.

Stantec was responsible for designing the new permanent bridge to replace the temporary bridge, along with associated channel improvements, roadway repairs, and the replacement of a large nearby culvert. Stantec also developed the temporary works plan for the construction scheme, which included innovative precast components, launching curved girders, and sliding the new bridge into place. Stantec provided structural engineering, highway engineering, environmental services, hydrotechnical engineering, traffic engineering, geotechnical engineering, construction engineering, construction supervision and Indigenous engagement on behalf of the FCA.

The FCA was committed to facilitating economic benefits to Indigenous people and Indigenous business through provision of procurement, employment, and training opportunities. Over $6M in contracts were awarded to Nation-owned companies.

Working closely with the whole FCA team, Stantec’s multidisciplinary design team worked on appropriate highway design details, drainage and channel issues, bridge design, traffic staging, and construction methodology to meet the project needs, aligning with the Alliance philosophy of prioritizing what was “best for the project”. To achieve the primary goals of safety, maintaining uninterrupted traffic, and opening the new bridge as soon as possible while dealing with the highly constrained steep mountain site, the team developed an innovative construction approach. The new three-lane bridge was built partially offset, opening to two-way traffic in this position. After the temporary bridge was removed, the new bridge was slid laterally into its final position during a brief traffic closure.

The Alliance model uses a collaborative approach throughout the project. From the onset, The FCA team worked closely together and met regularly to develop the design criteria and special specification requirements. This collaboration persisted throughout detailed design and construction phases.

Key factors of success in this collaboration included:

• Integrated team, allowing for seamless workflow throughout the project.
• Maintaining open dialogue throughout the project, so that all parties could voice their concerns and preferences, responding quickly to any changes needed.
• Shared risk model.

Collaboratively, the FCA conceived, designed, and built the Falls Creek Bridge quickly and safely. After mobilizing to the site in May 2023, the bridge opened to two-way traffic in December 2023 and slid into its final position in April 2024—less than a year after construction started and significantly under budget. The schedule, traffic, Indigenous engagement and development, and apprentice training all met or exceeded the goals, providing a strong endorsement of the Alliance Contract Model.