Two main water issues: contamination and ensuring the supply of clean water. One of the major reforms to the industrial city of the 19th century was the creation of sewer system. By mid 20th century, the volume of sewage and storm water exceeded the ability of most plants. Combined sewage overflow (cso) refers to the temporary direct discharge of untreated water. Occurs when a city has a combined sewer system which is prevalent in the urban centers in the. When it rains, the excess volume of sewage, clean water, and storm water is discharged untreated into r ivers. The discharge consists of many pollutants, untreated sewage and debris. Csos a re the sources for beach closings and contamination of water. Sanitary sewer systems have separate pipes that collect sewage and storm water separately. Excess storm water can overload the system and so storm water is discharged untreated due to r ain.
