JUST IN TIME FOR THE G7: REHABILITATING CALGARY’S 4TH AVENUE FLYOVER
Construction on the 4th Avenue Flyover rehabilitation began in the spring of 2024.
In the heart of Calgary, the 4th Avenue Flyover stretches 430 meters [1,411 feet] over the Bow River, connecting thousands of commuters to the city’s downtown core each day. Completed in 2025, this key piece of infrastructure required a full rehabilitation to restore its integrity and performance for the future.
The CAD $12.5 million upgrade extended the bridge’s service life by an estimated 35 years and included the installation of upgraded barriers, a high-performance polymer-modified asphalt (PMA) riding surface, and enhanced lighting — all while maintaining traffic flow through the city center.
OUR AMBITION: PREPARING TO PUT CALGARY ON THE WORLD STAGE
The 4th Avenue Flyover rehabilitation has included repairs to underwater piers, alongside replacement of the barriers and paving, and installation of platforms.
With Calgary preparing to welcome the G7 Summit in summer 2025, infrastructure performance and reliability were non-negotiable. The objective was clear: extend the structure’s life, enhance safety, and complete the work on a firm deadline.
Amrize was selected as the trusted materials partner to help meet this challenge. The company’s scope included:
- Concrete barrier replacement and refurbishment, in partnership with EllisDon
- Application of polymer-modified asphalt (PMA) overlay across the bridge deck
- Superpave asphalt placement on approach and departure roadways
- Curb and gutter replacement as directed by the City of Calgary
THE SOLUTION: HIGH PERFORMANCE ON A TIGHT DEADLINE
Our work on Calgary's 4th Avenue Flyover is complete, and all improvements are expected to be finished in fall, 2025.
Amrize supplied a suite of advanced materials, delivered with just-in-time accuracy to maximize efficiency on site:
- 50 m³ [1,766 ft³] of ready‑mix concrete for deck repairs
- 90 m³ [3,178 ft³] (approximately 175 linear meters) of new barrier wall construction
- 600 meters [1,968 feet] of bridge‑grade mastic asphalt installed using specialized echelon placement
- 440 metric tons [485 standard tons] of Superpave asphalt on the approach and departure roads
- 540 metric tons [595 standard tons] of polymer-modified asphalt (PMA) applied across the bridge deck
With limited staging space, all materials were batched off-site and delivered in tightly sequenced intervals. This ensured full use of every available work window while keeping the project on schedule and minimizing public disruption.
THE RESULTS: ONE SMOOTH RIDE FOR CALGARY’S COMMUTERS
The 4th Avenue Flyover was originally built in 1982 and cost approximately CAD $12.5 million to rehabilitate.
The 4th Avenue Flyover reopened two weeks ahead of the G7 traffic freeze, featuring smoother travel lanes, brighter LED lighting, and upgraded crash‑tested barriers. The structure is now projected to remain in service for at least another 30 years, significantly reducing future maintenance costs for the City of Calgary.