Design is already under way for an interim truss fender on the Ironworkers Memorial Bridge. A request for qualifications (RFQ) was issued last week for the undertaking of functional design work on permanent measures for both bridges. The successful tenderer will also lead stakeholder consultation.
The Lions Gate suspension bridge and Ironworkers Memorial truss bridge opened in 1938 and 1960, respectively. A number of safety upgrades have been done over the years, including extensive seismic upgrades.
At 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.
At 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.
Changes in vessels operating around the Port of Vancouver and updates to the national bridge design code had prompted the Ministry of Transportation & Infrastructure to review both bridges against the code. The review found that both satisfy vessel impact criteria for new bridges of regular importance (Class 2), but they do not meet the more stringent criteria for new bridges of critical importance (Class 1). Class 1 bridges are intended to be 10 times more reliable than regular bridges.
The study identified tangible measures to bring both bridges up to the more stringent Class 1 criteria, to strengthen their resilience in the unlikely event of a vessel impact.