"sm_jamieson" wrote in message
...
I've set out the main part of my drainage, being old clay to new
inspection chamber to rest bend and soil pipe etc, with the gradient
at 1 in 40. Two other connections on the chamber are to connect to two
roddable bottle gullies (one under outside tap, other for rain water
runoff - combined sewer).

Where do they still allow rain water to be connected into foul drains?
You could be in serious trouble, you would be around here.