ABSTRACT
The flows of wastewater originating from households, industries, and runoff from precipitation in urban areas are generally collected and conveyed for treatment and disposal. The systems used for this purpose are named sewer networks or collection systems. A sewer network is thereby defined as the wastewater system located between the sources for generation of wastewater and a wastewater treatment plant, alternatively, a point of discharge into an adjacent receiving water system. A sewer system consists of individual pipes (sewer lines) and a number of installations and structures, such as inlets, manholes, drops, shafts, and pumps, used to facilitate collection and transport. In the European definition, a sewer system is a network of pipelines and ancillary works that convey wastewater from its sources such as a building, roof drainage system, or paved area to the point where it is discharged into a wastewater treatment plant or directly into the adjacent environment (BS EN 752-1, 1996).
