Sewer fall insufficient

zagmund

Does anyone know what the options are for addressing a problem with insufficient fall in the sewer pipes leading to the main sewer at the edge of the road?

We have one pipe that comes out from the front of the house to the roadside which consistently gets blocked with, err, the heavier stuff from the toilet. After a while enough of it builds up that the whole sewer backs up and it gets unpleasant. The liquid tends to seep through over time so we're left with a solid volume. Getting the man out normally addresses this pretty easily, but I know we have an underlying problem which we need to address.

The drains coming from the back of the house & around the side all flow fine. This includes the waste from one of the two toilets in the house, the bath & the kitchen so the volume of liquid would be relatively high.

The problem begins where the second toilet joins the drain at the front of the house. This is in a relatively large manhole where (it looks like) the top of the original pipe was removed and access was gained that way. The other places where content joins the drain are in those square shaped junction boxes.

From what I can tell the fall is insufficient (or the rate of flow is too low by this stage).

The only options I can think of are -
1) relay the drain such that the fall is greater. This assumes that it's possible to join the mains at a lower point. I don't think relaying the entire drain around the house at a higher point is an option.
2) some sort of pump or mechanical thing to keep the flow going
3) brute force - pouring 100/200 litres of water down the drain every few weeks to clear out what has remained.

What other options might I be missing?

Thanks,

z

deandean

I would start by getting a CCTV survey done of the drains.

I had a similar problem a few years ago, it turned out there were a couple of little snags along the pipe that were causing solids to accumulative and after a couple of months, block the pipe and I would have to rod it.

One snag was a piece of concrete, the other was a piece of Wavin pipe not cut smoothly. I removed the snags and made sure the pipe was nice and smooth, I have not had any problems since.

Best of luck!

zagmund

Thanks - CCTV it is I think.

z