UNDERGROUND // CITY OF CALGARY

West Pine Creek Feedermain and Sanitary Trunk Project

Our project for the City of Calgary included a concrete water feedermain, concrete sanitary trunk, installation of water and sewer lines through incredibly difficult soil conditions and an open cut road crossing, which required working through the night.

CHALLENGE: There were numerous challenges with this project including the scope of the work as well as soil conditions, depth of cut and the fact that the project was taking place adjacent to Macleod Trail. With some of the most difficult soil conditions in the City of Calgary, plus the task of dewatering a wetland, we had our work cut out for us.

APPROACH:

Our plan was to work through the flowing sand section using a deep sump dewatering system, however the soil was so unstable that we couldn’t get the system installed without first stripping out the wetland soil, using fill to create a workable base, then excavating through the fill. In collaboration with our Earthworks division, the plan changed to a well point dewatering system as the deep sump system wasn’t performing.

OUTCOME:

Despite the many challenges, we finished on time and significantly under budget. Our crew’s technical experience expanded, and we built a relationship of trust with the client. As a forward thinking collaborator, we were able to dynamically change our original plans based on the site conditions, and not let the change affect the timelines or budget. In fact, in the end, we saved the City of Calgary $4,817,000.