Tensioning of a prestressing cable, 1964
![Construction workers working on a concrete structure](https://www.communitystories.ca/v2/pont-tunnel-louis-hippolyte-lafontaine_bridge/wp-content/uploads/sites/130/2020/01/PrtScr-capture_16.jpg)
Quebec Transport Ministry Archives
Tensioning was a dangerous operation, which required an expertise that was very rare in Quebec at the time. Engineers called on an American company specialized in prestressing to supervise the process.