Comox Lake Water Treatment Project

The CVRD is fortunate to have normally high-quality water for their supply.  However, Comox Lake also has many tributaries that carry sediment during and after major rain events causing turbidity in the normally crystal-clear water.  Therefore, the Comox Valley Water Treatment Project is implementing filtration to meet provincial surface water treatment objectives for drinking water.  The new water treatment system includes a new filtration plant, a new lake intake set at a lower elevation, a new lake shore pump station, and new transmission mains.  The treatment plant has an initial capacity of 80 ML/day expandable to 120 ML/day and includes three treatment processes: filtration, ultra-violet treatment, and chlorination in accordance with provincial requirements. Comox Valley RD

Because of the generally high-quality source water, either the membrane filtration or direct filtration (granular bed) plant can perform well.  Considering a number of factors, the Value Team recommended focusing on the direct filtration technology as this would simplify the system for handling filter backwash flows to reduce operating costs and to ensure that the backwash system does not become the limiting factor in the plant’s ability to perform as designed.  The single direct filtration solution would provide a 10% savings of the original expected capital budget.