Existing & Future Scenarios: Populations, ICI Equiv, & Inflow & Infiltration (033-DP-1)
Discussion Paper Summary
Part of the planning for wastewater treatment in the Core Area includes predictions and preliminary designs for sewer pipes, collection systems and inflow and infiltration. Inflow and Infiltration (I&I) is rainwater and groundwater that enters the sanitary sewer system. The CRD already operates a program designed to reduce I&I rates in the region. Reduction of I&I can decrease the costs of conveying and treating wastewater.
Core data from many previous studies was compiled and updated for this report. The data, which includes population increase predictions, I&I increases (if any) and sewer infrastructure network predictions, gives the CRD a more thorough understanding of the issues at work with respect to wastewater conveyance from homes and buildings to treatment facilities.
Population in the CRD’s Core Area is expected to increase to 395,720 by the year 2065, from 270,936 in 2006. Areas of particular growth include Colwood, Langford and View Royal, whose populations are predicted to more than double.
Along with population increases, the CRD has also looked at potential sewer infrastructure growth during the same period. Major growth of sewered areas is expected to occur in Colwood and Langford, with sewered areas growing from 557 hectares to 2371 hectares by 2065.
Infrastructure decay and climate change both have the potential to impact I&I strategies in the CRD, with replacement predicted to be needed at a rate of 1 percent per year. Based on climate change predictions, I&I rates could increase as severe rainfall events increase. Ongoing monitoring of I&I rates and climate change will be necessary to accommodate wastewater flow into the future.
© Image courtesy of Evan Leeson