Starting today and lasting until Friday, August 14th, the 4th Avenue bridge will be closed for inspection by bridge specialists. This is the city's preliminary step in assessing how best to repair the historic Thunderbird Viaduct.

The inspection will consist of detailed visual inspections as well as a condition survey that will check the rebar, corrosion potential, as well as any kind of degradation that could impact the bridge's integrity.

Director of engineering services for the city of Moose Jaw, Bevan Harlton, says that the survey is a necessary starting point for the project.

"From that, we will have an understanding of what deficiencies exist, and then from there, what sorts of things we will need to do to rectify those problems and start planning designs and cost."

Once finished, the specialists will be able to offer the city a number of options for repairing the bridge.

"What close at hand maintenance can we do to keep the structure functioning as it is? What are some more significant capital upgrades that we can do to improve the overall structure? And beyond those, what would it cost to increase the load-bearing of the bridge."

Harlton says that the viaduct's current load rating of ten tonnes makes it difficult to operate heavy maintenance machinery on its surface.

"It's been deemed safe for regular traffic but it causes difficulties with maintenance in terms of the equipment need for fixing potholes or repaving."

He notes that simply fixing the potholes without addressing the underlying structural issues would be a poor use of the city's resources.

Once the report is in, the city will be holding info sessions with the public to hear and weigh the options for the bridge's future.

 You can find out more about the viaduct's history here.