Sewerage

Sewerage is the infrastructure that conveys sewage. It encompasses components such as receiving drains, manholes, pumping stations, storm overflows, and screening chambers of the combined sewer or sanitary sewer. Sewerage ends at the entry to a sewage treatment plant or at the point of discharge into the environment. It is the system of pipes, chambers, manholes, etc. that conveys the sewage or storm water.

According to this definition, sewerage and sewage are two different terms. However, at least in American English colloquial usage, both terms are sometimes used interchangeably.

Design aspects

The main part of a sewerage system is made up of large pipes (i.e. the sewers, or "sanitary sewers") that convey the sewage from the point of production to the point of treatment.

Types of sanitary sewer systems include:

Effect on water table

Sewerage systems often reduce the water table in areas, especially in densely populated areas where rainwater (from house roofs) is directly piped into the sewerage system as opposed to being simply allowed to be absorbed by the soil. In certain areas it has resulted in a significant lowering of the water table. In the example of Belgium, a lowering of the water table by 100 meters has been the result. The freshwater that is accumulated by the sewerage system is then piped to the sea.