Public or private lateral drain?

[magicnumber7]

Building a side and rear extension on the outrigger of our ground floor Victorian terrace flat. I have an access chamber and a drain that runs down the side return into the garden and into a public sewer that runs across the back of the terrace gardens. Our neighbours' drainage goes into the drain on our land. Is the drain in our garden still private, or is it public? We are in a thames water area. Thanks.

 

[frutbunn]

There was a change in the legislation wherby all drains serving more than one property are now classed as public sewers, however not all are plotted. You need to contact Thames water, if it is not plotted they will still need to be made aware. I've got no experience that far South but the last one I had up here I drew a drainage layout and they arranged to meet the owner and survey the drain.

 

[oldbutnotdead]

Where the drain becomes shared the water co become responsible for it. Have a look on their website, there are usually pretty pictures

 

[DevilDamo]

As others have already mentioned, it is a public sewer and would require some form of consent from Thames Water. You can read about the process and fees here...

https://www.thameswater.co.uk/media...r-our-pipes/building-over-or-near-a-sewer.pdf

You may be able to take advantage of the self-certification option providing you meet the relevant criteria. Failing that, it’ll be a traditional Build Over Agreement.