The Ministry of Transportation and Infrastructure is moving forward with retrofit designs to further strengthen the Lions Gate and Ironworkers Memorial bridges, to keep people and goods moving safely.
Changes in vessels operating in the Burrard Inlet, and updates to the national bridge design code, prompted the ministry to review both bridges against the code in spring 2015. The review included consultation with the Vancouver Fraser Port Authority, the Pacific Pilotage Authority, BC Coast Pilots and the Transportation Safety Board of Canada.
The review, which is now complete, found that both bridges satisfy vessel impact criteria for new bridges of regular importance (Class 2), but they do not meet the criteria for new bridges of critical importance (Class 1).
The study identified tangible measures the ministry is now pursuing to bring both bridges up to the more stringent Class 1 criteria, to further strengthen their resilience in the unlikely event of a vessel impact:
- Lions Gate Bridge: The existing concrete collar protection at the base of the south tower will be enhanced with an in-water rock-fill berm. (The north tower is already protected by a rock-fill berm.)
- Ironworkers Memorial Bridge: A steel barrier will be added to protect the trusses, and in-water deflection structures will be installed close to the bridge.
Design work is underway for an interim truss fender on the Ironworkers Memorial Bridge. A Request for Qualifications (RFQ) is being issued today on BC Bid to undertake functional design work, and lead stakeholder consultation to move forward on the measures above.
The Lions Gate and Ironworkers Memorial bridges, built to the standards of the day, have operated safely since opening in 1938 and 1960, respectively. The ministry conducts regular inspections on both bridges, and a number of safety upgrades have been done over the years, including extensive seismic upgrades.
Class 1 bridges are of critical importance to the transportation network, having an exceptionally small annual risk of collapse of less than one in 10,000. They are intended to be 10 times more reliable than regular bridges. Class 2 bridges are of regular importance, having a very small annual risk of collapse of less than one in 1,000.
The Port of Vancouver extends from Roberts Bank and the Fraser River, up to and including Burrard Inlet. The Port of Vancouver is Canada’s largest port, supporting trade with more than 170 economies around the globe.
Approximately 3,100 vessels travel through the Port of Vancouver annually, including container ships, cruise ships, automobile carriers, tankers, bulk carriers and breakbulk carriers.
In 2017, 142 million tonnes of cargo moved through the port, valued at $200 billion. One-third of the value of Canada’s trade in goods outside of North America moves through the Port of Vancouver, including consumer products, food, grain, automobiles, lumber and other natural resources.
As part of its federal mandate to ensure goods are moved safely through the Port of Vancouver, the Vancouver Fraser Port Authority has many safety procedures that are regularly reviewed and updated. All deep-sea cargo vessels are steered in and out of port by experienced B.C. coast pilots, who combine their local knowledge with advanced marine navigation equipment. Other measures vary, based on the type and size of the vessel, but can include assistance by tugs, speed restrictions and specific transit windows based on tides and currents.
To read the full reports on Risk Assessment and Mitigation for the Lions Gate Bridge and the Ironworkers Memorial Bridge, go to:
- Lions Gate: www.gov.bc.ca/transportation-reports-lower-mainland#lionsgate
- Ironworkers Memorial: www.gov.bc.ca/transportation-reports-lower-mainland#ironworkers