Definitions for "Combined Sewer"
a sewer system that carries both sewage and storm water runoff. Normally, its entire flow goes to a wastewater treatment plant, but during a heavy storm, the volume of water may be great enough to cause overflows of untreated mixtures of storm water and sewage into receiving waters. Storm water runoff may also carry toxic chemicals from industrial areas or streets into the sewer system.
a sewer that carries both storm water and sanitary sewage (wastewater from your drains and toilets) to a treatment plant for treatment
a system of single pipes that collect both wastewater from homes, businesses and industries as well as surface runoff from rainstorms and snow melt