The High Level Bridge won’t be able to support LRT trains and a shared-use path on the upper deck, according to a new report commissioned by the city.
Stantec engineers inspected and measured the 106-year-old bridge, and found corrosion and loss of steel beams caused the structure to lose strength.
“We were mildly surprised,” said Jason Meliefste, the city’s branch manager of Infrastructure Planning and Design.
The High Level Bridge was the preferred river crossing for the new Centre LRT, which would link the downtown core, University of Alberta, Strathcona and Bonnie Doon.
Meliefste said the bridge is safe for drivers and pedestrians using the lower deck, but it would not be able to carry the weight of LRT trains even with extensive upgrades.
“It's the additional loading associated with LRT is what really tips it over the edge. Having an LRT that runs on a five-minute frequency in two different directions means 24 trains an hour," he said.
"That adds a significant amount of loading compared to what it’s currently being used for."
It would be council’s decision whether the bridge is ruled out of the Centre LRT project.
As part of the feasibility study, engineers also investigated whether the lower deck’s sidewalks could be widened.
They found it would be “marginally feasible,” and it would come with a $23.7 million price tag.
Rehabilitation work to extend the life of the bridge was done in 1995. Meliefste anticipates the structure will have more work done in the near future, some time in the 2020s.
