New connection to a manhole. Is this OK?

[capital1965]

I have just had some drainage work done and it was not what I expected. I wanted a new pipe running into an existing drain and it benched. Clearly I didn't communicate this very well (it was all done

by phone they they did visit prior to look at ) because I have a new pipe that just drops in as in the picture. There is a 90 mm drop from the IL of the new pipe to the bottom of the existing benching it will fall into. The company say they do it like this every week and offer a 5 year guarantee. Is it OK.

 

[Hugh Jaleak]

No, that is awful! Discharge needs to go into the main channel in the direction of flow and at a much shallower angle. Any discharge from that pipe will shoot straight into the connection opposite, and there is a high probability it'll cause waste to back up in the other inlet beneath the new connection, blocking up both the other inlets before long.

You may, subject to Levels, be better off breaking that chamber out and fitting a Plastic Chamber in its place, at least then you might stand a chance of getting the connections made so they flow properly and don't foul the opposite side.....

It goes without saying Building Control haven't seen it I am sure.