Fort York Pedestrian and Cycle Bridge, Toronto

This scheme has been under development since the late 1990s. It's a project to build a footbridge in Toronto linking two areas severed by a huge set of railway tracks, and connecting the historic Fort York site.

The design was for a bridge following an S-shaped curve in plan, with the deck supported on alternating inner edges by inclined arches. The alignment follows that of a historic watercourse, the Garrison Creek. The bridge deck is 234m long and 5m wide. Preliminary designs were developed by Stantec with Montgomery Sisam Architects (see PDF for more images).

The scheme had a budget of CAN$18m (£11.4m), which I would have thought was sufficient for a bridge of this type and scale, working out at nearly £10k per square metre (compare the somewhat similar Peace Bridge in Londonderry, with a reported budget of £8.7m).

However, tenders have come in at just over CAN$22m, and Toronto's council has decided it can't proceed. This is hardly the first time a local council has struggled with cost escalation on a landmark footbridge scheme, I've featured several similar cases here in the past. The council has sent this one back to their staff, asking them to come up with a cheaper scheme.

"No one ever dreamed that we would be looking at something that looked like a Golden Gate Bridge," said one councillor. Really? The bridge design has been around for some time, with the design team drawing clear comparisons to the York Millennium Bridge and Gateshead Millennium Bridge in their presentations [PDF, see page 64]. So, no Golden Gate, but surely nobody ever thought they were looking at a bargain-basement design either.

Looking at the design images, there are clearly options which will save money (including going back to simpler alignments, as previously considered and discarded). It would be possible to keep one of the two inclined-arch spans over the wider railway corridor while reverting to shorter spans over the smaller railway lines and the area of land in between.

Presumably, the cost of erecting the inclined arch over the railway is a major contributor to the over-budget tender prices, as it's a form of structure completely unsuited to this sort of space. It's not suitable for launching, nor is there obvious space for the temporary supports required while a 100m+ long arch is assembled piecemeal. From that perspective, you might think it was an odd choice to begin with, one which ignored rather than worked with the engineering constraints.

The local press are lining up to support or attack the council's decision, while a Facebook / Twitter group has been set up seeking to protest the cancellation via petition.