VSCL was contracted to install a new sanitary trunk line using both open-cut excavation and trenchless installation (Micro-Tunnelling). The work includes the relocation of an existing water main, and construction of a new roadway, concrete flatwork, and installation of a new storm line for the width of the Right of Way.
The contract is part of the expansion of the sanitary system for North Calgary, as well as future growth north of the city. Construction for the majority of the project has been through an active commercial/industrial mix use area within the city of Calgary. All work that must take place while ensuring that access is maintained at all times to local businesses and the City of Calgary Spring Garden Yards.
Excavation depths for the open-cut portions of the project in live roadways range from 6-8.5m, next to an existing and active 1500mm RCP sanitary line.
VSCL was contracted to install a new sanitary trunk line through a non-active landfill that was capped in the late 1940’s. The work included the relocation of an existing water main, and construction of a new roadway, and concrete flatwork within the width of the Right of Way.
The work through the landfill necessitated the development of a specific Health and Safety plan to deal with the potential contaminants expected within the non-active landfill area. At all times during this phase of the work, the trench had active fans circulating air, with active and passive air quality monitoring taking place. All excavated material was hauled to the Shepard Landfill and was replaced with drainage gravel for the pipe zone and imported clay backfill. One of the more interesting installation issues on site was that some zones would have the pipe sitting on top of garbage. As it would not be economically sound to excavate to competent base material, concrete slabs were built to increase the surface area and bridge the poor base. The slabs were installed below the pipe bedding and the pipe installed.
The sanitary lines installed for the project ranged from 1800mm to 2700mm RCP, installed to depths between 5-11m.
All work on the project was completed with no serious incidents involving Safety or the Environment.