Thames Water Application

When building a home extension, adding a garage, conservatory or annex, it is highly likely that there will be drainage pipes in your land that require attention. It is important that you do not conform with building regulations but also inform Thames Water to ensure that the pipework is correctly protected and that you do not cause any restrictions.

Whose responsibility is this?

Sewers are the shared pipework between the drainage of two or more properties. If your property was built before 1937, the sewer will be a public sewer. If your property was built after 1937 it is most probable that the sewer is private and you are responsible for this.

When improving your home and building near a sewer, you may be required to divert your drainage away from foundations and outside of the footprint of your build. To do this, you will need permission from Thames Water. This is done in the form of a ‘Build over’ application and requires you to have architectural drawings of your existing and proposed drainage route, along with cross-sectional foundation plans. Here at TLC, we prepare all of the necessary drawings and take care of your application- and all you need to do is wait for the permission letter to go ahead with the works.

Example Thames Water Application drawings (click to view full size)


Call us: 0752 504 1120 or 0208 361 7458 (office)
TLC Planning and Design
33 East Barnet Road
New Barnet
Company number 10266155

Working in the London area, including
Barnet, Bounds Green, Camden, Chingford, Crouch End, Enfield, Hendon, Edgware, Finchley, Ilford, Leytonstone, Muswell Hill, Palmers Green, Southgate, Stoke Newington, Walthamstow, Winchmore Hill

Working in the Essex area, including
Brentwood, Buckhurst Hill, Chigwell, Church Langley, Dunmow, Epping, Harlow, Loughton, Ongar, Rayleigh, Romford, South Woodford, Wanstead, Woodford

Working in the Hertfordshire area, including
Bishops Stortford, Borehamwood, Broxbourne, Cheshunt, Hertford, Hoddesdon, Letchworth, Potters Bar, Radlett, Sawbridgeworth, St.Albans, Ware

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