Upgrade of a major sanitary trunk sewer in the environmentally sensitive Nose Creek valley

Nose Creek Sanitary Trunk Sewer Upgrade – Phase A

Located within an environmentally sensitive area, the Nose Creek sanitary trunk sewer required a significant upgrade. We worked with the City of Calgary to minimize impacts while keeping a diverse range of stakeholders including the Calgary Zoo, two golf courses, and several community associations engaged.

Numerous environmental assessments, a geotechnical investigation, and a detailed review of existing utilities and existing/proposed transportation infrastructure were completed to assist with route selection for the 4.2 kilometre upgrade. Three critical crossings were identified that included a major roadway, the Trans-Canada Highway (TCH), and a creek. Trenchless and conventional construction methods were investigated and evaluated for each of the crossings. An open cut (isolation) crossing method was selected for Nose Creek, and tunneled crossings for Memorial Drive and 16th Avenue (TCH).

The presence of a formal landfill site further complicated the project. The team developed mitigating measures and successfully implemented them for the portion of the sewer (including the Memorial Drive tunnel) that crossed the landfill.