Beyond its striking appearance, what purpose does this curving steel giant serve? We are standing before the Cherry Street South Bridge. It is more than just a structure. It is a key piece in Toronto’s ambitious waterfront revitalization.
The Cherry Street South Bridge is part of the Port Lands Flood Protection and Enabling Infrastructure project. This 1.3 billion dollar project aims to reshape downtown Toronto. The project includes resilient flood protection measures. It also includes urban renewal initiatives and a network of four innovative bridges.
This plan will revitalize the Toronto Port Lands. The area is an industrial and recreational waterfront neighborhood. The project involves excavating two new outlets and a new mouth for the Don River. It cleans polluted land and designs habitat-rich wetlands. New transit infrastructure is being built. Twenty-five hectares of publicly accessible green space and parkland are being created. The PLFPEI project provides crucial flood protection against extreme weather events. It also increases harmony between urban life and natural habitat preservation.
The PLFPEI project commissioned four signature bridges. They enhance accessibility between downtown Toronto and its reinvigorated waterfront. The bridges facilitate three critical waterway crossings. Aiming for a symbolic representation of the city’s innovation, the bridges serve as vital conduits. They carry light rail, vehicular, bicycle, and pedestrian traffic.
Three of the new crossings span the Cherry Street area. These are the Cherry Street North bridges, the light-rail transit system bridge and the Cherry Street South Bridge. They offer panoramic views over the newly naturalized Don River mouth. The bridges seamlessly connect to the southern Port Lands. The Commissioners Street Bridge spans approximately 150 meters. It traverses the naturalized riverbed and wetlands. It links the eastern expanse of the Port Lands.
The design team worked closely with Waterfront Toronto. This public organization spearheads the PLFPEI project. They ensured that the bridge designs aligned with the goals of the master plan. The team included schlaich bergermann partner’s New York City office. They collaborated with the local Toronto office of engineering firm Entuitive. Grimshaw Architects’ New York City office also participated.
The design team was tasked to create “bridges to the future”. These bridges embody Toronto’s leadership in design and manufacturing. The team crafted a double-curved shell structure. It reimagines common tied-arch bridges. The innovative approach uses the principle of a tied arch. The arch is made from double-curved steel plates. This maximizes material efficiency and reduces costs. It also addressed key challenges such as foundation limitations due to challenging soil conditions.
The Cherry Street South Bridge features multiple piers for continuous beam action. This mitigates structural demands in the deck girders. The self-anchored design obviated the need for extensive horizontal support forces. This streamlines construction and enhances overall project feasibility.
Contaminated soil in the industrialized Port Lands created challenging site conditions. As a result, the structural system was chosen to maximize vertical reaction forces. It minimizes lateral reaction forces and reduces any foundation works. The site location at Lake Ontario allowed the design team to conduct most of the bridge construction off-site. The final delivery of the bridges was completed by barge.
The double curvature of the steel shells posed a unique fabrication challenge. Innovative shipbuilding manufacturing processes were required. Central Industry Group, a Netherlands-based specialist, was enlisted to manufacture all double-curved plates.
Once assembled, the bridges were painted and transported via barge on the St. Lawrence River. They arrived at their designated locations in the Toronto Port Lands. Each bridge was rotated into the correct position using a barge. Then it was lowered directly onto previously constructed abutments. The final step was pouring the concrete deck.
The Cherry Street South Bridge opened in October 2022. The surrounding park landscape, which is anticipated to be finished in 2025, will enhance the experience. The successful realization of this infrastructure project enriches the cityscape. It facilitates community connectivity.
So next time you cross the Cherry Street South Bridge, remember its story. Think of the collaboration, innovation, and engineering. The bridge represents Toronto’s commitment to a vibrant and sustainable future.