Jungleboy Before you get the big hammer out lets just talk a little further. We would say your house was built about early 1950s. We stopped using the old LCC cast iron stink pipes and tarred Hessian sand and cement jointed clay pipes round about 1960.
Now everything we say will be assumed that standing on your lawn and looking at the back of your house.
Your house is a semi and the house on the left hand side, the garden is raised approx 450mm above yours. On the right hand side is another semi with say approx 3metre gap between yours.
You say that you do not really want another inspection chamber in the patio. Would we be right in assuming that the other manhole is by the heap of hard core against the hedge. Difficult to see in photo.
If this is a manhole, then we are confident that the house on the left has a shared connection with you and their effluent is running through the pipe in your garden to the manhole by the hedge, then either turning 90 degree and out to main sewer, or carrying on past next pair of houses to a point where it will turn into main sewer.
If this is the case, means you will be working on live drain, but no problem, come back to us and we will tell you easy way to do it. If you do not know how to check it out, come back and we will tell you. Do not think rain water will be hooked in to connection unless you know for sure you are on combined drainage system.
Would be very interested to know whether we are right or not.
old un