Construction on the rock hard Canadian Shield is never easy at the best of times and comes with even more complications when it involves diverting a community’s sewage from one treatment plant to another, as was the case with the $11-million Nickel Lift Station upgrade and forcemain project in the City of Greater Sudbury.
This recently completed two-component project involved the construction of a two-metre-deep 2.9-kilometre-long, (1.8-mile) 600-to 750-mm forcemain from the Nickel Lift pumping station in the community of Copper Cliff to Sudbury’s wastewater treatment plant on Kelly Road and a 600-mm gravity sewer along that road.
Although open cut was used for much of the route on a city-owned right of way on Regional Road 55, trenchless technology had to be utilized for some sections with either natural or man-made barriers, says Akli Ben-Anteur, the city’s water and wastewater projects engineer
“Trenchless technology is used by the city when there is a need to avoid any major disturbance/impact to existing infrastructure, environment, business and residents.”
Certainly, a lot of rock was encountered during the excavation and the main challenge was to maintain uninterrupted service to the community, he points out.
In this particular project Greeley Ontario-based Marathon Drilling Co. Ltd. used a combination of horizontal drilling and a jack and bore operation to cross under a CP rail line, Regional Road 55, a privately-owned rail bridge, Nickel Street, and a small water crossing.
The exact breakdown was a 140-metre-long (459-foot) stretch to jack and bore under the bridge, rail line and highway and horizontal drilling below the creek and the street for a total distance of 430 metres (1,410 feet), says Ben-Anteur.
Locally based Denis Gratton Construction Ltd. was the general contractor overseeing the construction of the forcemain which commenced in December in 2017 and was completed this January.
The second phase of the project was the installation of new pumps and significant upgrades to the pumping station by Belanger Construction Ltd. That work started in early 2018 and is scheduled for completion this month (February), says Ben-Anteur.
In a sense the origins of the project are a combination of history and geography. For many decades Copper Cliff was a separate municipality and all its wastewater flows were collected at the Nickel Lift station and pumped to the privately owned Inco (now Vale Inco) wastewater treatment plant.
“This private wastewater treatment plant is at its end of life cycle and is in a state of disrepair and it became apparent that we needed to find a solution,” says Ben-Anteur, in explaining the need for the project.
A major recommendation in the city’s water and wastewater master plan was to transfer all of Copper Cliff’s wastewater to the Kelly Road plant because of its proximity and has the available treatment capacity, he points out.
Design work by consultant R.V. Anderson Associates Limited began in 2016.
The new forcemain came in operation in December and switch from the old to new systems was achieved without major complications thanks to a risk management plan and other intensive studies, says Ben-Anteur.
No environmental assessment was required as the forcemain was installed on the city’s right of way using the trenchless technologies and the required upgrades to the station were completed entirely within the building.
The project also included a watermain upgrade and road reconstruction with bike lanes along Kelly Lake Road from the wastewater treatment plant to Lorne Street, he says.