Darwin Bridges

Given the architectural richness of the area, an effort has been made to ensure that the Darwin bridges blend harmoniously into the environment. Shapes, proportions, materials, and surface treatments were chosen with the objective of designing elegant, sober, and uncluttered structures. The result is a unique elegant movement effect spanning the 37-metre length of the infrastructure.

For decades, almost all transportation infrastructures were built for the sole use of the automobile. However, the growing number of pedestrians and cyclists today requires that we rethink our approach.

The reconstruction of the Darwin bridges uses locally sourced recycled glass, becoming the first in the world to use glass powder concrete, a new material that incorporates fine ground recycled glass. This type of concrete, also referred to as ground glass pozzolan (GGP), replaces 10% of the ternary binder required with recycled glass powder. By using GGP, we saved approximately 40,000 kg of concrete and used a total of nearly 40,000 kg of recycled glass – the  equivalent of 70,000 wine bottles.  This 100% Québec-based, patented innovation results from 17 years of research carried out by the University of Sherbrooke and Ville de Montréal.

Composed of GGP, the Darwin bridges’ lifespans will extend over 125 years, compared to 75 years for a conventional concrete structure. The bridges present new sustainable materiality, making a world premiere in urban development.

Between the two lanes of the bridges, the central strip opens and deepens, drawing in two arches from the road, which then slope down towards the cycling path. Complex geometric precast concrete retaining walls are installed between the bridges to create vegetation-lined levels. Extensive landscaping of trees, shrubs, and indigenous plants enliven the bridge perimeters and promote biodiversity. In keeping with the naturalistic approach of the structures, the landscaping around the bridges creates a soft, inviting, and colourful atmosphere. The landscaping of the site was also designed to serve as a wetland area and rain garden for the harvesting of runoff water.