Mistissini’s innovative wooden span wins top engineering honours
Mistissini’s new concrete-on-wood bridge carried home a special prize from the Association of Consulting Engineers of Quebec (AICQ) awards gala in Montreal May 11.
The project’s engineers received the Transportation Infrastructure award for the 160 metre-long, glue-laminated, wood-beam semi-continuous arched structure – the first design of its kind in Quebec. According to project manager Alessandro Cirella, a wooden structure of this length is unique in Quebec. It was also the only nomination to win in its category unanimously.
“We are really honoured to receive this award and to have been selected as the lead engineers on this project,” said Cirella. “We have done work in Mistissini in the past, and we are always very happy to work with them because they have an incredible team of people. It is quite pleasant to work with them and we are exceptionally proud that they let us work on a wooden bridge.”
According to Emmett MacLeod of Mistissini’s Capital Works Department, the decision to go with a wooden project instead of the standard concrete on steel project was not only about cost effectiveness but also about local employment spinoffs.
MacLeod said that while it might have been a challenge to get everyone on board (so to speak) with a wooden I-beam structure, the design proposal by the team from Dessau (which has since been purchased by Stantec) made the most sense when it came to the environment and cost effectiveness.
Another major factor in this was the fact that steel I-beams would have to be manufactured in and imported from China, adding an additional six months to the project timeline.
“However, our neighbour over at Chantier Chibougamau was able to manufacture them right there in Chibougamau,” said MacLeod. “So when it comes to any potential maintenance that needs to be done, which will be every seven to 10 years to put more coating on the sides, they can fabricate pieces that can be installed right away. We now have the means for maintenance right there and so this was a matter of practicality.”
For MacLeod, this award is a very satisfying experience because of the effort that went into the project that was several years in the making. It also had to jump through many bureaucratic hoops as it is the only project the community has ever built on land that is Category I, II and III.
Built over the Uupaachikus Pass, the bridge gives Mistissini access to much-needed gravel and aggregates for public works projects. Without access to this area, Mistissini would have to import material from Chibougamau.
Looking back on his, Cirella spoke of the Crees’ “vision and wisdom” in taking a chance on a wood-laminate bridge.
“We feel very fortunate that they gave us this opportunity to take that risk. Until we actually designed it, we didn’t know what we might encounter. A bridge of that nature and of that length made out of wood was a first for us and it is a first in Quebec. It has never been done here before and that is why this was a real technical challenge. So I am really glad that they gave us this opportunity to go beyond and think outside of the box,” said Cirella.