Hi Hopefully someone can advise...
I am in the process of planning a new rear extension with a ground bearing slab. There will be an existing manhole bang in the middle of the new floor. The manhole is brick construction with an invert of 550mm below existing ground level.
The foul drain serves a number of houses along the run (I am halfway along the run) and I am told by Thames Water that it is classed as a Public Sewer (but my property deeds say it is a private system..?) However, my questions are:
Will I need to move the manhole to the shared alley way between with all new/extg drainage connections diverted?
Can I build over with the slab and not do anything?
Will this be expensive?
Your BCO is the only one that can give a definitive answer, but my guess would be that you'll be required to shift the existing manhole and it would probably cost a grand or two, just depending on how much effing about is involved.
