Difference between drains and sewers
A drain is a pipe that serves only one building, conveying water and waste water away to a sewer. A lateral drain is a section of drain positioned outside the boundary of a building, connecting with the drains from other buildings to become a sewer.
Sewers (sewerage), are the underground networks of pipes that carry sewage (waste water and excrement), waste water and surface water run-off, from drains to treatment facilities or disposal points.
Property owners are responsible for the maintenance and repair of drains inside the boundaries of their property (unless the drains of other properties run through their property).
Since 2010, most private sewers and lateral drains that connect to the public sewer network are owned by the regulated sewerage companies.
Some buildings have drains that connect to a cesspool, septic tank or treatment plant rather than a sewer.
[edit] Related articles on Designing Buildings Wiki
- Cesspool.
- Drainage.
- Drains.
- Groundwater control in urban areas.
- Lateral drain.
- Maintenance of drainage systems to prevent flooding and water pollution.
- Manhole.
- Pipework.
- Private sewer.
- Public sewer.
- Rain gutter.
- Rainwater downpipe.
- Safe working in drains and sewers.
- Sewer construction.
- Sewerage.
- Sewerage company.
- Stink pipes.
- Sustainable urban drainage systems SUDS.
- Waste water.
- Water transfers and interconnections.
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