Collection Systems Technology Fact Sheet - Sewers Conventional Gravity

Sewers are commonly referred to according to the type of wastewater that each transports. For example, storm sewers carry stormwater; industrial sewers carry industrial wastes; sanitary sewers carry both domestic sewage and industrial wastes. Another type of sewer, known as a combined sewer, is prevalent in older communities, but such systems are no longer constructed. Combined sewers carry domestic sewage, industrial waste, and stormwater. This fact sheet focuses on sanitary sewer systems.