ECES Technical Talk

The Mill Creek Combined Sewer Trunk built in 1958 conveys wastewater and rainwater from south Edmonton to the Gold Bar Wastewater Treatment Plant. Because of the poor to very poor physical condition in Mill Creek Ravine section, the trunk was determined to be a high priority rehabilitation project for EPCOR. The main scope of rehabilitation includes 890m of 2100mm diameter new tunnel with two shafts, 200m of local sewer reconnection, and abandonment of 860m of existing trunk. The construction was completed with 3 Stages. The first stage of the project construction was a micro tunnel which began in March 2023 and was successfully completed in June 2024. The second stage is local sewer reconnection which was started from May 2025 and completed by November 2025 with hand tunneling and open cut excavation. The last stage of trunk abandonment includes one working shaft and 4 bulkheads. Backfilling with Flowable Self‑Compacting Cellular Concrete Grout was completed by early May 2026. 

The 99 Avenue Sanitary Trunk Bypass is a two-stage project to ultimately rehabilitate an approximately 1.1 km of cast-in-place concrete arch shape sanitary trunk sewer in Edmonton, Alberta that has been in service for over 70 years. The existing trunk is a crucial link in Edmonton’s wastewater collection system receiving flows from Edmonton’s west end. Phase 1 of the project includes the construction of a ~1.6 km long, 1,800 mm inside diameter bypass sewer, to divert flows for the Phase 2 trunk rehabilitation, and ultimately increase conveyance capacity. The existing tunnel is approximately 30 m below ground, and as such microtunnelling was specified as the required installation methodology for the bypass. The construction methodology included three drives: ~975 m long, which included a sensitive crossing of the MacKinnon Ravine; ~390 m long; and ~250 m long. Stage 2 involved sliplining discrete segments of 950 mm span by 1400 mm rise non-circular fiberglass liner into the existing host tunnel (approximately 1200 mm span by 2000 mm rise) via worker-entry.

Speakers:

Gary Fei, P.Eng., Project Manager at EPCOR, will provide an overview of the Mill Creek Combined Sewer Rehabilitation Project, covering project planning, detailed design, and construction.

Yang Bai, Construction Manager at Shanghai Construction Group (Canada), will present details of two award-winning projects, including the state-of-the-practice of trenchless construction techniques, the challenges encountered during construction of underground structures, and the resolutions that led to successful project completion. 

Registration:

• Fee: $10 for ECES Member | $20 for guests – includes food and light refreshments 

• Link: Fill out the registration form or visit ECES Website

• Deadline: May 26, 2026

Parking Options:

• Street meter parking

• Impark Parking at 10022 100 Avenue: $5 flat rate after 5:00 PM (see map below)