Collapsed drain

[KirstenBlest]

Calling @PigletJohn please.

I think that the drain running through my garden has collapsed.

The concrete is cracked and looks to be sinking in places. It is outside the house but I live in a terraced house, and where it goes from there is probably under next door's extension.

What do I do, and how urgent is it?

Phone your local water / sewage company i.e. Thames Water, Yorkshire Water etc depending on where you live. If you're in a terrace it's likely to be a shared sewer and therefore their responsibility.
I'd say it's pretty urgent because if it's partially collapsed it will be more prone to blockages and once that happens you're looking at sewage backing up into homes and gardens. If it's completely collapsed then it will definitely flood sewage.

Thanks emmathedilemma.
Any idea how much it will cost?

some photos will help

that part of the drain that runs directly from your house alone, is your responsibility; but those parts receiving water or sewage from two or more houses are the responsibility of the water company.

How old is your house?

Is it at the front or the back?

btw the beighbours are not allowed to build over a sewer without a build-over consent

which they are unlikely to have

@KirstenBlest if it's a shared drain then the water company will cover the cost.

A responsibility picture.

This applies in England.

see also
www.ofwat.gov.uk/nonhouseholds/supply-and-standards/responsibility-supply-pipes/

Hi PigletJohn,
Thanks for the reply.
House is Victorian. approx 1890.

It is just outside the kitchen, running across the width of the property.

At the right hand side looking away from the back of the house, it's about 120 cm from the outside wall. On the left hand side it is about 30 cm away.

The width of the property is about 5 metres.
House is end-of-terrace, with next door on the left if standing at rear of the house.

Here is a diagram. the grey bit is the cracked concrete, where it is quite dense it is where it looks like it has sunk a bit.

The purple squares are manhole covers.

The image is not drawn to scale but gives an idea.

if you are end of terrace, it looks from the pic like there is a good chance that the manhole belween your kitchen and the shed is where a common sewer behind the terrace turns down towards the road, if there is a clear gap here at the side of the house.

in which case it is likely the grey section will be water co responsibility.

they will probably know responsibility as soon as they lift the covers and look at the direction the pipes take.

A house of your age will have been built with salt-glazed clay pipes, which are pretty certain to have been cracked and broken since 1940.

There will be some pipes running from your house to the common sewer, and I would strongly recommend that you have them dug up and replaced with new at the same time, because they are pretty sure to be the same age and the same condition. They usually break at the first bend or trap nearest the house.

You might be able to get the water co's builders to do it for a cost; otherwise you'd need to find local builders; but certainly the best time to do it is when the sewer is being renewed.

Gosh, thanks PigletJohn.
I hadn't thought that it would be connected to the street , but there is a stopcock and a manhole outside at the front. and it makes sense with what you just posted.

I'm the end-of-terrace at the top of a very slight incline. I was a bit scared of opening the manhole cover in case it had Other NDN's sewage in it.

NDN's extension probably didn't get planning permission.I have wondered about that in the past. I don't get on great with NDN. but he lets the property and I only see him once every few years.

A stopcock won't be for the sewers, that'll be your water supply.

a sewer manhole would be about 2ft x 3ft, a stopcock cover will be about 6ins x 9ins

Yes, that's about right, Piglet John.

I had to locate the stopcock when I was having something done. Can't remember what. There's the usual stopcock under the tap too.

The one outside the front is in the street, and I'm not sure if it turns off the water for the block of terraced houses.

If it's a stopcock it's in no way related to the drainage network (if it was you'd all be dead by now!!).
Have you phoned the water company yet?

No, but if the water coming in is shared, the drains might be shared.

Just phone them! If you're in a terrace then there's a very high likelihood that the drains are shared. Better to do it before a more serious issue materialises!

Thanks. I'll do it tomorrow if I can.

The phone lines will be open until late if not 24/7

Can you lift your manhole cover?
I lifted mine and it was patently obvious, even to my delicate eyes, what the problem was.
We're in a terraced house house too - mid terraced here, but with a shared drain.
Water company have been pretty good and carried out some repair work.
The leaky drain ,however, has caused other issues and the saga is continuing at Wingedharpy towers.
Good luck.

Our house suffered with a collapsed drain and a whole corner of it had to be rebuilt. So yes, it's very serious! Get it checked out.

It’s probably just a bit of sunken/cracked concrete? If the drain had collapsed enough for the ground/concrete above to sink then you would have had blocked drains by now.

If you know anybody with some drain rods then you can push them down to the spot where you think you have a problem and have a “feel” to see if there is anything there. I tend to find the round brush head attached on the end works best.

The drains aren't blocked but there are some issues that might be related.

The end wall isn't in the best state and I am now worried sick that I may have subsidence or something.

Need to hoick up my big girl pants

If it’s not blocking, and it’s victorian then I would say the clay pipe is just cracked and water has been slowly leaking out for some time. It will have waterlogged the area around the crack and made the ground around it soft , which in turn has made the concrete crack.

It’s not a big job to dig it out and repair it. The hard bit is just digging the hole 🙂 The sooner you do it the better.

You will be able to see how deep the pipe is by looking in the manhole.

Our drain wasn't blocked either because the water had found an alternative place to drain.
No smells.
No damp patches but, some cracks inside house.
Wingedharpy towers currently being monitored for subsidence right now.
The thinking is that water from drains has washed away some soil around foundations.

Start by looking down the manhole OP then take it from there.

Hi there, wondering if @PigletJohn or any other lovely person might be able to give advice on a clay pipe issue we’re having…. we are having extension built, we have in place a build over license, but discovered clay sewage pipe (we are end of terrace) which will be under our new kitchen is cracked… builders replaced with plastic, approved by architect but should it be clay?? Building control raised the question but are happy with plastic but it has taken 4 weeks for BControl to tell us this… and have told us Thames Water would expect it to be replaced by clay… architect has now put ball firmly in our court 😬… complication being that builder is concerned that fitting clay may crack other part of pipe belonging to neighbours and also under their extension! We are SO stressed! Architect thinks, off the record to keep plastic and no one will ever be the wiser but can we take that risk!?!
hope this makes sense!!