laying a new sewer pipe...

CamperMan

a question about sewage pipes.

we have to connect the house to the public sewage system, the end of the public sewage pipe is in our garden, 2 metres down.

an inspection chamber will go into the 2 metre deep hole, I do not want to have to dig a 2 metre deep trench by hand from this point to the house, is it possible to lay the pipe from the house at about 1.0 metre underground, then a 90 deg drop to connect to the bottom of the inspection chamber at over 2 metres?

This isn't a question about will it meet guidlines, I am asking WILL THIS WORK, or could the contents of the toilet get backed up going down the last 90 deg drop to the 2 metre deep connection

Poor Uncle Tom

Well, if you think logically about it, a first floor toilet connection does the same thing to the outside svp.

But regarding manholes, it is unlikely you would be allowed to make drop manholes any deeper than 1m each, so you could have 2 drop manholes close together to get the full 2m drop carried out properly.

mickdw

If ground levels allow, you might get the pipe down to about 1m due to normal gradient from the house then use 1 drop manhole to get it down to 2m.

aujopimur

Contact your local co./city council, they will let you know whats required.

Max Moment

What you are looking to do is called a 'back drop manhole' and is a fairly standard drainage detail. Basically, you let your new foul line run into the new manhole / inspection chamber at the normal gradient. Back a few hundred mm upstream you fit a 'y' branch and then a 45' bend to give you the vertical stack. It's important to fit a 'y' or swept 'T@ and not a straight 'T' as the solids will overrun the 'T' Junction and you will end up with blockages.

From this you fit your standard vertical stack and then fit another 90' bend at the bottom and let the pipe run into the invert of the existing LA manhole. Back up at where your pipe protrudes into the manhole, you fit a stopper or cap. Should the vertical part of the backdrop become blocked, you open the stopper or cap and can rod or jet it freely.

Another option is a ramp Manhole. Have a look at pg 15 of the attached for an idea.

Also, you want to keep the lower inlet up halfway on the existing line through the LA manhole to prevent disturbing it's flow.

CamperMan

Thanks Max Moment..

the "Ramp Manhole" looks like a plan,

you see from where the ground floor toilet will be to the inspection chamber connected to the public sewer is just 6 metres long, that is why I want to lay the pipe from the house at about 1 to 1.2 metres below ground then drop it near the IC to connect at below 2 metres.

This is for our house in Germany, here, the local council don't really seem to care how the property is connected so long as it is CONNECTED and they can collect the waste water charges

muffler

CamperMan please dont use this forum looking for advice on matters that are outside of Ireland.

Thread locked.