Fitting a gulley riser, new problems found.

[limakilo]

Morning everyone,

So I noticed I was getting a lot of splashing from my gully's/drains. I noticed the gully's/hoppers sit below the paving, and water was getting onto the soil. To that end, after looking around on here I decided I would raise the gully's with risers, and do any remedial concrete/mortar business to secure it, and fit new gulley surrounds. So I inspected them more closely, and that is where problems appeared...

Clearly the gully is full of junk, and I know why as you can see below..

From this, I gathered dirt was ingressing into the gully from the poorly fitted (is it fitted at all) surround and gully. And quite potentially the crack that is running down the side of the gully.

There are two other inlets either side on each other corner of the house, a gulley like this one, and a soil stack. These two appear to work fine.

My biggest concerns are water going below the surface at this broken gully, and the gully otherflowing. I can get all the dirt out, and I think I can rise the gully and install a new surround, but my question is, do I need to replace the split gully, or is it repairable?

Any help is much appreciated

 

[Ian H]

I'd say it's not repairable.

I'd pull all the gunk out (it probably came off the roof) and fill it with water. If the water level drops then water is leaking from the crack.

If you get a new gully a good one is a 4D900 from Travis Perkins. You can raise them with a short piece of 6" plastic pipe and join them to the clay with a AC4000 band seal.

 

[^woody^]

The cracked piece looks like a riser section, not part of the actual gully or trap. If so its not a problem

Extend the downpipe into the gully and you avoid water going anywhere but down the drain

 

[limakilo]

I'd say it's not repairable.

I'd pull all the gunk out (it probably came off the roof) and fill it with water. If the water level drops then water is leaking from the crack.

So potentially not leaking. That would be a rare stroke of luck. That will be the first thing I try.

If you get a new gully a good one is a 4D900 from Travis Perkins. You can raise them with a short piece of 6" plastic pipe and join them to the clay with a AC4000 band seal.

So this is the most likely situation. The paving looks like it will just lift up, so hopefully I can get a decent work area and hole to work in. Am I being optimistic in thinking they just slot together?

In terms of foundations, once fitted, would I just put a bed of some gravel, then concrete it underneath? I don't imagine I encase the whole thing in concrete?

The cracked piece looks like a riser section, not part of the actual gully or trap. If so its not a problem

Extend the downpipe into the gully and you avoid water going anywhere but down the drain

If it is a riser part, could it not let dirt enter the drain over time? Also, how likely is it that water levels would be high enough to reach the cracked riser? If it was occasional assuming it drains properly would this be a problem?

On asking that question, once its cleared I could probably indentify where the water sits.

What's the chances of that sludge blocked more of the pipe? I would be best removing it at the point as much as possible rather than flushing it away?

 

[^woody^]

If there is a trap, then water in the gully will only ever be as high as the trap, so not right up the extension pipe.

Soil entering through that crack is minimal. But if you wanted to, you could dig a bit of the soil away externally and spread a bit of mortar or sealant on the pipe.

Water exiting from the inside is not going to be in such quantities as to cause a problem.

Downpipes should always discharge into gullys, not over the top of them - that is the biggest issue.

 

[Ian H]

There will probably be gunk round the back of the trap but you will be able to loosen it with your fingers before you put the water in.

The 6" riser and 4" pipes do push into the gully and the adaptor to clay has a jubilee clip with 8mm head. Hardest thing will be cutting the clay, I use a grinder with no guard but obviously wouldn't recommend you to do the same.

If the collar on the first section of clay stays intact you could mortar into it.



First thing though, clean it out and post another picture.

 

[limakilo]

Had a quick blast this evening, managed to get all of the mud out of the vertical part, I think. It doesn't appear to be very deep because I think I've found the bend, and that seems good and blocked, I'm pretty sure I was pulling bit of brick, nails and god knows what else out. I'll give it a crack tomorrow morning. Anything else I can use to unblock that? I bought a ladel and got most of it out but seems stuck.

 

[Ian H]

A rubber glove and a small screwdriver/spoon should help get stuff back from the back of the trap.

Is there a manhole anywhere near? Once you think you have cleared it you can run some water down and see if it flows through the manhole.

 

[limakilo]

A rubber glove and a small screwdriver/spoon should help get stuff back from the back of the trap.

Is there a manhole anywhere near? Once you think you have cleared it you can run some water down and see if it flows through the manhole.

I will give it a go in the morning. That should hopefully sort the blockage completely.

One thing I did notice, the water IS draining very slowly. I'm not sure if this means its draining through the blockage slowly, and those cracks aren't completely open and leaking. Or its not going through the blockage at all, and it is only leaking through the cracks. Potentially both but all shall be revealed tomorrow.

As for manholes, there are none on my property, none that are visible anyway. If there was a blockage in the main drain, wouldn't one of the two drains either side overflow too?

 

[JohnD]

you have a clay gulley, which we know is broken and leaking, and may have sunk in the ground.

IMO it has probably broken at the bend and has been leaking for 50 years or so, turning the ground to mud and washing it away o form a cavity.

Plan on digging it out and replacing.

you may find red worms, and mortar washed away between the bricks, and perhaps a degree of subsidence.

 

[limakilo]

Downpipes should always discharge into gullys, not over the top of them - that is the biggest issue.

When you say this, do you mean the downpipe should physical open inside a gully? This all started because I was ****ing about doing something else outside, my girlfriend unplugged the bath, and water come flying out a drain like a fireman's hose! Thought that can't be right so started digging around.

 

[limakilo]

you have a clay gulley, which we know is broken and leaking, and may have sunk in the ground.

IMO it has probably broken at the bend and has been leaking for 50 years or so, turning the ground to mud and washing it away o form a cavity.

Plan on digging it out and replacing.

you may find red worms, and mortar washed away between the bricks, and perhaps a degree of subsidence.

Bloody hell, you don't sugar coat it do you! That sounds just about my luck to be honest. If I got a builder in to do that, what type of financial
punishment am I looking at?

 

[JohnD]

you've got a spade, haven't you?

 

[limakilo]

you've got a spade, haven't you?

I'm not Alan Titchmarsh, will probably have to go and get one won't I. If I'm honest I don't really have much of anything, and since I bought this house I've found myself buying all kinds every weekend. A month ago I had a screw driver, tomorrow, a spade.

 

[JohnD]

hee hee, been there, done that.

In my first house I was standing in a hole digging out my broken gulley, when my neighbour got out of the bath and pulled out the plug. My hole filled with warm soapy water from next door's drain.

All the houses in that terrace (same age, same building materials and techniques) had broken gullies.

And soil pipe rest bends.

That was in London, where the soil is soft clay. At the end of the road a wartime bomb had demolished a row of houses, and the shock wave rippled the ground.

Other parts of the country may be different.