Broken gulley and trap?

[splinters]

Just out cleaning the patio i noticed a fishy smell from the rear waste gully and the slate chippings in the channel nearby was wet and slimy (smelt bad too). Scraping back the slate the soil was wet and black. I looked in the drain itself (the gully?) and it is about 1 foot deep. I got gloves and reached down to find a lot of gunge in the bottom of the gully as it goes into the trap. I got a hose and blasted the rubbish through but it felt as if the pipe had cracked. I cannot see any damage down the pipe but felt a sharp edge under the bend and was able to drag out some black soil/stones from what felt like the crack.
I am awaiting a builder to come out and quote but a few questions.
If the pipe is cracked, how come the water remains at a constant level i.e. around 3 inch above the bottom?
Would a leak really make it back up to the top of the soil (under the slate chippings)? There is a chance the waste water from the washer has simply splashed onto the slate chippings as it hits the grate on top of the drain.
Is this an urgent fix? We had the patio (slate) laid a few years ago and there was no evidence of leaking then.
If i recall the Water Board came and fixed the same area around 12 years ago.
Any and all help is appreciates guys before i get stung by a builder. The trap/gully is glazed earthenware by the way and the house was built late 30's.

 

[HERTS P&D]

You will need to get this fixed, as excess water going under you house will damage your foundations, over a long period of time, just ask Sarah Beanie.

Let us know what the builder says.

Andy

 

[splinters]

I will do, but something confuses me. Having cleared out the gunge in the gulley/trap and rinsing the rubbish off the slate. I noticed it has dried out around the hopper (the ground with the loose slate on it). Also, as this is a trap, would the water level not drop if it were a crack in the pipe?
I am starting to suspect that the 'gunge' and damp is over spill from the hopper (waste water from the washer spilling out onto the slate over several weeks). This is further evidenced by the fact that the damp/gunge is only on the slate next to the hopper but as it goes past the wall along the side of the house it is bone dry.
Will investigate further but the 'crack' I can feel is right under the trap if that makes sense. Is there a chance I am simply feeling where the waste pipe to the sewer is cemented into the gully?

 

[HERTS P&D]

Try posting a picture.

Andy

 

[Burnerman]

Its possible that may have just been the gully overflowing due to a blockage.
Why not run plenty of clean water through to make it wholesome, then pump out the water in the trap with a wet vacuum? At least you'll see better.
You wont be able to reach right around the bend with a salt glazed gully and you may just be feeling a 'snot' on the mould.
If the gully holds water then the crack must be above that level,I reckon.
If it is leaking though, replacement is essential - listen to Andy! If it isn't filled around about with concrete, excavation isn't so bad.
John

 

[splinters]

Don't worry guys, I have every intention of getting it looked at. I just like to be well armed when builders I don't know turn up sucking through their teeth.
I rang one place and got quoted £295 without looking at it. Another 'reputable' company said they have a flat day rate of £585+VAT...that is some call out if it is simply blocked.

It is definitely holding water steady just as it always has and I hosed it out until clear and can see no cracks etc. down to where the water goes into the trap. Your explanation makes sense, i just thought it would all be a single smooth casting where the trap is, perhaps I just felt a lip and dislodged a pile of gunge caught on it?
The smell and damp is just around the hopper part where it meets a 6 inch border filled with green slate chippings. As the border goes down by the side of the house, there is no problem and at around 4 feet away is the down pipe from the bath/toilet. It was blocked a while ago (cotton buds!!) and easily cleared out. There was no sign of damage there and we have had no building work done on the house in at least 15 years.

 

[splinters]

Try posting a picture.

Andy

Just going out mate and will post one later, but I doubt you would see anything in it; it smells bad and there is nothing to 'see' in the drain/gully.
If it rained the slate chips and underlying soil/sand next to the hopper would be equally wet.
Take your point though. In the meantime is there anything to look for to verify a leak without excavation? The drain has a hopper and a straight drop of a little over a foot then you can see where the water goes under (trap?)...

I will get a photo, makes more sense

 

[splinters]

Aaah, the plot thickens...I am not sure if you can see from the photos but there is something grey at the bottom of the gulley. I reached in and pulled out a block of concrete about the size of a large breadcake. It looks to be the same shape as the bottom of the gulley so either some concrete has been poured down there and set or I just pulled the bottom out of it... 15 minutes later and water level is still as it should be....this is probably why I thought the 'trap' had collapsed or broke (I was reaching into the gap between the top of the trap and this lump of concrete?
Photos attached to make it a bit easier...you are all probably wondering what the hell is wrong from these...


Err....images are in my album, how do I show them here? This is the link in case you can do it that way:
//www.diynot.com/network/splinters/albums/9266

To further complicate matters I just noticed my wife has been out to water the hanging baskets...guess what? they drip nicely onto the strip of slate including where it is sodden. Perhaps it is just getting saturated from above ground?

 

[Burnerman]

I reckon this is just a false alarm.....occasionally a cement bucket gets washed out and chucked down the drain. Often its tile cement or grout but I'm not going down that route
Keep an eye on it, and see that there's always water in the trap.
John

 

[splinters]

I know exactly what you mean mate...when we had the last 'blockage' fixed, the builder cemented the base back in...i think i found where he poured the old concrete.
So, if there is water in the gully, there is likely no leak in the trap?

 

[tryitandsee]

It's probably not a bad idea anyway, to scrape away slate chippings and then remove the damp smelly soil for a depth of 1 to 2 foot and replace with large size shingle or more slate chippings although later quite expensive. In other words create a 'french drain'.

This will allow the water to disperse/evaporate and help dry things out a bit.

Also when laying slate slaps two years ago, did the base get compacted with a mechanical whacker plate. May have got to near gully and cracked something you cannot see.

 

[splinters]

We used a compactor where the grass had been but this area of the garden was already paved, we just replaced with indian stone slabs, dot and dab on a sand base i believe.

 

[HERTS P&D]

What is the waste pipe, is it from the kitchen/washing machine?
Your 'concrete' in the gully could be washing up powder that has gone hard, it does look like concrete. I have seen it many times (Does your wife do the washing at 40 degrees?)
Turn on the tap/ washing machine and see if the water spills over the edge. This could cause a smell as the waste water is splashing around the outer edge of the gully and soaking into the surrounding area.

Andy

 

[splinters]

Pipe is from sink and washer. I watched it tonight and the water never rose above the level it is always at. Oh, it was definitely concrete, albeit akin to ready mix with a stone or two caught in it. Definitely no overspill in terms of rising water but occasionally the pipe gets moved a little and water splashes onto the surrounding are especially if the sink is emptied at the same time.

 

[Hugh Jaleak]

I would be inclined to clip the pipe to prevent it moving, and possibly take a hacksaw to the grating and cut a slot out, then extend the pipe to discharge below the grating.