Sewer Chamber 'removal' - How?

[BobTheBear]

Me again with another question

In constructing a new sewer chamber outside of the extension area, the old sewer chamber has to be removed.

Taking down the bricks is easy enough, but I have to replaced the 1/2 sewer with a new piece of VC 6" sewer.

The sewer is obviously live, although never much flow from upstream.

If I'm careful I might be able to remove the old cut piece of sewer, but how do I replace it with a new piece. Can I just lay a piece in its place, I dont think so. It will have to be fixed together with a couple of those rubber couplers. But if i slide them up the sewer and then put the sewer in place, it wont fit because of the concrete under the existing cut sewer (I'm presuming there is concrete in place. If it is sitting on a lean mix, then I might have a chance I guess. The sewereither side of the cut sewer obviously has to be joined to and again if there is concrete underneath, I;m going to have problems cutting it away without breaking the sewer.

Couple of pictures below, as you can see it's not that deep, just a couple of feet

Any thoughts appreciated, thanks

 

[Hugh Jaleak]

The existing chamber will have to be removed. I'd dig out and expose a couple of feet of pipe either side to begin with. Go gently though, those salt glazed pipes are fragile, and may well fall apart at the joints if there is no concrete holding them in place.

Once you've exposed either side of the chamber, carefully cut through the pipes, then break out the chamber from the middle. Once all the debris is removed, (fit a bung in the upstream section if you dont want to be paddling and dont forget to remove it when finished!!!!), cut a piece of your new pipe to suit. Vital to carefully chamfer all cut edges of the pipes, you dont want any edges where material can catch. Fit new pipe. Bed and surround with peagravel.

 

[BobTheBear]

Thanks Hugh, I thought as much - remove it all!

Can I get a piece of 6" VC pipe in one length?

I only ask as the original pieces seem to be in short lengths with collers very often.

 

[Hugh Jaleak]

Salt glazed pipes were/are made in 3' lengths, laid spigot to socket and jointed with a tarred gaskin and mortar mix. To replace with VC look at 'Supersleve', comes in 1.75m lengths, and is bl**dy heavy! These are plain ended, joints are made using plastic collars, although I'd think one length would suffice for your needs. Alternative is plastic, 3m lengths.

 

[BobTheBear]

Thanks Hugh, that supersleve looks just right for me

Thanks again