storm sewer

A storm sewer is a conduit designed to carry surface runoff, such as rainwater, away from urban areas to a point of disposal, typically a stream or river. These systems are distinct from sanitary sewers, which carry domestic and industrial wastewater to treatment plants.123

Storm sewers are usually constructed from reinforced concrete or corrugated metal pipes. They are designed to utilize gravity for flow, with inlets called catch basins strategically placed to collect surface water. While some storm sewers may include detention basins for temporary storage, pumping stations are generally avoided due to the large volumes of intermittent flow they would need to handle. Modern civil engineering practices favor separate systems for storm water and sewage to prevent overwhelming treatment facilities during heavy rainfall.23