WIRRAL COURT PUMPING STATION INFLOW AND INFILTRATION REDUCTION PILOT PROJECT
Civica undertook this pilot project and was tasked to develop a robust I/I reduction strategy that met the following objectives: (1) Identify the cause of high flows entering the Wirral Court Sanitary Pumping Station (SPS), (2) Propose remediation works and develop private side initiatives that will bring the I/I generation rates below the firm capacity of the SPS under wet weather flow conditions, (3) Establish I/I Reduction Strategy standards that can be rolled out across the City of Toronto. Part of this project required the use of 50 flow monitoring and micro-monitoring stations to pinpoint localized areas of I/I to better rationalize locations for detailed investigations. Using a combination of monitoring analysis, field investigations, and historical records, Civica identified significant I/I sources that would reduce 55% of the peak flow to the pumping station upon remediation. The I/I sources identified include defects on both private property (residential downspouts, commercial roof drains, reverse slope driveway drains, and private laterals) as well as those on public property (mainline defects, maintenance holes susceptible to flooding, etc.). A detailed I/I reduction strategy report was produced for this project, which included recommended sources to remediate, cost estimates, risk assessment, and timelines. A business case report was also produced as part of this project, which analyzed the cost-benefit analysis for various types of remediation works.