I'm planning to build a garage in a position where a public 6" sewer will intersect with two of the walls in plan view. I've got all the official documents from Severn Trent about how to apply for permission, and about before and after CCTV surveys and all that.
The general principle seems to be that building foundations must be taken down to sewer invert level to avoid any possibility of the sewer pipe being loaded by the building - but I'd like to know how negotiable that is - and whether anyone here has ever been given official permission to do anything different.
In my case, the sewer is about 2.4 metres below the surface, and the soil - apart from a few inches of topsoil hasn't been disturbed for nearly 40 years - when the sewer was laid. If I were to excavate to 1 metre, and lay normal foundations as if the sewer wasn't there, there would still be well over a metre of well compacted clay soil between the bottom of my foundations and the top of the pipe. It could possibly be argued that the sewer pipe is far less likely to be damaged by this approach than by excaving down to 2.4 metres, and exposing the pipe. [I'm not sure how controllable a digger bucket is at that depth - when the operator can't really see what he is doing!
Any comments - particularly from anyone who has been down a similar road?