By rosebell
Enhancing the capacity and reliability of Calgary’s wastewater system, the Inglewood Sanitary Trunk (IST) project has been completed by the City of Calgary has in two phases over 10 years. Currently, it is fully operational and is due to serve neighbourhoods in Calgary’s north and inner city through to 2076.
According to senior project engineer Melanie Gray: “This is a major milestone for Calgary’s wastewater infrastructure. Our team has focused on building a system that could meet the demands of a growing population, while minimising impacts to the environment and surrounding communities. I’m incredibly proud to see this project through to completion.”
In order to constructing a new sanitary trunk line to carry wastewater from the Inner City Trunk in North Inglewood to the Bonnybrook Wastewater Treatment Plant, phase One involved 3.5km of microtunnelling and 250m of open cut work and was completed in November 2020. This work increased capacity and improved service reliability for several inner-city communities.
With the aim of linking three existing sanitary trunks on the north and south sides of the river, phase Two included almost 600m of microtunnelling beneath the Bow River to create two, 500m tunnels. Additionally, construction of a 90m tunnel to connect Phase One and Phase Two as well as 20m of open cut work on the north side of the river were the contents of this phase. Phase Two was crucial in completing the system loop and enabling the full functionality of the new sanitary trunk.
Both phases of work required a total of six tie-ins to existing sanitary lines and moving power, water, sanitary and storm lines, along with obtaining four private land agreements to complete the 10-year project.
