Transmission Main Repair

Transmission Main Repair at 17 Street & Sherwood Park Freeway

GS Construction successfully completed a 900 mm Transmission Main Repair in Edmonton at the intersection of 17 Street and Sherwood Park Freeway on behalf of Strathcona County. The project involved critical excavation and replacement of an existing Concrete Cylinder Pipe (CCP) under a strict shutdown timeline.

The work was carried out within a 40-hour shutdown window, requiring continuous, around-the-clock operations. Careful planning, precise execution, and strong coordination across multiple specialized crews ensured the transmission main was safely repaired, tested, and returned to service on schedule.

As part of the repair, crews installed a 24-inch bevel gear gate valve and a 900 mm line stop to allow controlled isolation of the affected section. The live transmission main was exposed at two locations, enabling the use of an existing air vent and the installation of an additional 2-inch air vent through hot tapping. These measures supported effective draining and controlled commissioning of the system.

Following isolation, crews completed an 8-metre pipe replacement, installing fully restrained couplings to ensure long-term performance and structural integrity. Once complete, the system was backfilled, re-pressurized, and commissioned with time remaining in the shutdown window.

This project demonstrates GS Construction’s ability to deliver complex, time-sensitive watermain repairs while maintaining safety, coordination, and reliability. The successful execution minimized service disruptions and reinforced the integrity of critical municipal infrastructure.