The City of Mission operates a drainage system through out the City. The system is a combination of enclosed pipes and open channels. Most of the urban areas have an enclosed system typically referred to as the “storm sewer system” with most rural areas having open channels typically referred as the drainage system and collectively referred to as the storm drainage system.
Storm Sewer versus Sanitary Sewer
The sanitary sewer system typically referred to as the “sewer system”, collects and disposes of waste and fluids from the internal plumbing system (toilets, shower, bath, laundry, sinks etc) of homes or other type of buildings. The storm sewer system typically referred to as the “drainage system”, collects and disposes of the water from outside of the buildings, (roof down spouts, foundation drains, driveways, lawns etc.).
The City of Mission operates both a Sanitary Sewer System and a separate Storm Sewer System. Some communities operate only a single sewer system (often referred to as a Combined Sewer System) where both internal and external fluids are collected and disposed of via a single sewer main system.
For further information see Sanitary Sewer System.
Storm Drainage System
The storm drainage system is a combination of 100 kilometers of storm sewer mains, 140 kilometers of roadside ditches plus even more kilometers of creeks, streams and small rivers. The entire system is gravity (flows down hill) with the exception of where 3 dyke pump stations, operated and maintained by the City, pumps water through the dykes during high water level caused by the Fraser River Freshet.