Jump to content

Buchan trap

From Wikipedia, the free encyclopedia

A Buchan trap (alternative names: Bristol interceptor,[1] interceptor trap and disconnecting trap) is a device fitted in a domestic sewer pipe to prevent odours entering the pipe from the public sewer[2] and permeating the house, a common problem before individual plumbing fittings were separately trapped. The trap is made from fireclay[1] and uses a water seal to prevent air passing from the sewer to the pipe. Waste flows from the house through a U-bend in the trap. This means that there is always water in the pipe preventing the passage of anything from the other direction. The device is a large clay U-bend with an air-inlet/access point on the 'house' side. It is located below the ground level, but can be accessed through the air-inlet and sometimes a rodding hole.[2]

Blockage risk

[edit]

The Buchan trap will collect solids, sludge and waste that is not in suspension. In recent times, non-paper based wipes have posed a particular problem, according to most Water Authorities. The end result of these adverse conditions is a partial or complete blockage. The sewage/rainwater then backs up the pipe and exits from the lowest connected appliance (sink, bath, dish washer, washing machine, etc.). This can be a significant problem in multi-level dwellings (e.g. tenements) where those at the lowest level will receive all the waste waters from those above. They should be checked, and cleaned if required, on a recurring basis, such as annually.

History

[edit]

The Buchan trap was devised in the 19th century to stop the flow of sewer gases due to the miasma theory of disease.[1] For example, it was believed that the disease cholera was an airborne infection, not waterborne. The Buchan trap is normally found in the bottom of manholes or drop-shafts. It normally denotes the end point of the domestic property's sewer before it joins the main public sewer.

References

[edit]
  1. ^ a b c Jack, Ian (22 November 2014). "Buchan trap, blind siphon or Bristol interceptor – whatever you call it, it's playing havoc with my drains". The Guardian. Retrieved 28 February 2024.
  2. ^ a b "Technical Data: Back Bristol Interceptor Code KBBI - NAT 137" (PDF). W T Knowles and Sons Limited Tel: 01422 372833. Retrieved 28 February 2024.