St. Albert North Interceptor Sanitary Trunk

Growing cities present challenges to wastewater management. That was the case for the City of St. Albert. Their sanitary collection system was nearing capacity during periods of peak flow. In particular, the South Sturgeon interceptor trunk sewer was overloaded and operated under surcharged conditions. The City needed our help to upgrade the sanitary system to provide in-line storage, conveyance capacity, system controls, and staging options needed to accommodate the needs of existing and future development.

We conducted a feasibility study to carry out a staged sanitary trunk sewer upgrade. Our team successfully designed and implemented Phase I, providing immediate benefit of interim storage and flow equalization while reducing disruption to the neighborhood and traffic. Construction involved microtunneling of approximately 2,100 meters of 1,200 millimeter diameter trunk sewer to be installed at depths up to 22 meters.

By using microtunneling during construction, we reduced impacts to a historic neighborhood, allowed the pipe to pass under a 25 m high hill, and minimized disruption to a busy collector road, transit route, three nearby schools, and an assisted living facility—benefitting the community now and in the future.