Improving wastewater capacity

Trunk Relief Initiative, Third Sewage Forcemain

High rainfall events throughout the summer of 2015 forced the City of Regina to follow emergency procedures for extreme weather events at the McCarthy Boulevard Pump Station (MBPS) to avoid the sanitary sewer system from becoming overwhelmed. Unfortunately, this procedure resulted in discharging excess flow—screened but untreated—to Wascana Creek. Following this event, the Saskatchewan Water Security Agency (WSA) directed the City of Regina to reduce the risk of wastewater bypasses at the MBPS. Our job? Recommend solutions to upgrade the system to meet a 1 in 25-year storm-event service level.

The first phase of the improvements included preliminary design, detailed design, and engineering services for the construction of a new 1,500-millimetre PVC forcemain, the first ever use of this size of pipe for a pressure application in Canada. This 4.3-kilometre forcemain now connects to the valve chamber at the Regina Wastewater Treatment Plant, a system that allows high wastewater flows to be directed into storage in former treatment lagoons to avoid negatively affecting the treatment process and the plant.

Now that the Third Sewage Forcemain is complete, the City of Regina can move forward with the second phase of the work involving pumping upgrades at the MBPS which are required to take full advantage of the additional forcemain capacity.