Greater Nanaimo Pollution Control Centre (GNPCC) treats wastewater from approximately 108,000 people in the City of Nanaimo, Snuneymuxw First Nation land, and the District of Lantzville. GNPCC also treats septage from residential onsite (septic) systems and wastewater from pump-and-haul properties.
Sewers are built to follow the natural slope of land, allowing gravity to do most of the work to transport wastewater. Low elevation areas use a pump station to pump the wastewater to a treatment plant. GNPCC uses three pump stations: Wellington Pump Station, Departure Bay Pump Station and Chase River Pump Station. View a map of the sewer service area.
The GNPCC provides primary and secondary treatment and removes more than 90% of the biochemical oxygen demand (BOD) and total suspended solids (TSS), two of the main methods used to measure wastewater quality. Learn more about how treatment works and the different levels of wastewater treatment.
Biosolids, a soil-like material produced during the wastewater treatment process, are managed in the RDN's Biosolids Management Program.
GNPCC treated over 12 billion litres of wastewater in 2024. Treated wastewater is discharged into the Strait of Georgia 2,030 m offshore at a depth of 70 m. For more information see the 2024 GNPCC Annual Report.