If you were wondering why traffic on the Trans-Canada Highway was reduced to single lane near the downtown Tim Hortons Monday, the cause lies with an older water main.
City contractors were replacing a 300-mm cast-iron water main with a PVC (polyvinyl chloride) one.
Jenn Wilson, city engineer, explained on May 25 that the majority of the project is relocating the pipe off the shoulder of Highway 1 and into McGuire Lake Park.
A large rectangular pit was dug on Sixth Avenue NE, which she described as an open-cut tie-in. Open-cut is the traditional method of excavating the roadway and then working in the trench.
She said the park will not be dug up to accommodate the relocation, as the directional drilling method used requires excavations only at the tie-in points “which allows for minimal disturbance of the park.”
Wilson estimates the water main is about 40 years old.
“Which is not old for a water main, but cast iron mains are particularly susceptible to corrosive soil conditions. We’ve had a fair amount of breaks in CI (cast iron) mains throughout town and due to the size and location of this one it was deemed high risk and slotted for replacement.”