Broken gully

[amfisted]

Hi All

Looking to replace a broken rainwater gully--pics below. The old one, as can clearly be seen, is broken at the first bend.

Someone has cut two slots in the face of the gully downpipe and when I excavated I found that a land drainage pipe (the yellow flexible stuff) was resting against these slots, though probably not doing a great deal drainage wise.

The ground is clay and there's not really enough space in the vicinity for deep soakaway, so if possible I would like to install a fitting which has a removable blank in the front face to allow reattachment of the land drainage pipework, which would come in from the bottom left of the first (and last) picture.

So to the questions: firstly, what type of plastic fitting do I require to replace the clayware gully in the pics, where do I cut the old clay pipe to attach the plastic-to-clay adaptor, what adaptor do I need, and finally, is there a fitting I could get which would allow me to attach a land drainage pipe to the front face of the new gully?

Links to the exact fittings would be most welcome, and thanks in advance.

 

[amfisted]

Well, for what its worth I managed to work the problem out for myself. I obtained a bottle trap with a second outlet for the land drain, a flexible bend fitting that you can adjust to different angles and a PVC to clay adaptor, along with a 3m length of underground PVC pipe to make the joints. Deciding which fittings to use turned out to be easier than expected, but only because by the time I had a clean cut on the clay pipe it was more or less exactly level with the trap outlet. Originally it would have been higher, but the first cut failed when the pipe fractured just beyond the old spigot fitting and my only option for the next cut was about eight inches further on. Had I been more experienced in this type of thing I would probably have made my cut there in the first place.

My problem now is that despite much bailing with a bucket and shovelling of mud into bags, the sub base above ground after backfilling remains stubbornly wet due to seepage of ground water from the sloped part of our garden. I probably need at least three days of dry weather before I can consider the ground sound enough to finish the surface with some riven paving; and three dry days is a lot to ask for in North Wales.

 

[Madrab]

Glad you got it sorted AM. Sounds like you've got the same type of weather as we do up here

Sometimes these unique one off jobs need a singular on site point of view, that can make it difficult to be helpful in an online forum.

 

[amfisted]

Aye, fair point.

I suppose when it comes to drainage, there's no "one size fits all" solution because every site and every situation is slightly different. And when you're trying to connect up to old fittings you can never be sure that the situation as you first find it will remain the same, given the likelihood of breakages. On the plus side, having done this job I'm much more aware of the types of fittings which are available, what they do and how they are likely to suit a particular situation.

I have another broken gully to replace on the other side of the house, and even if that site is different to this one I hope to be able to find a solution using the knowledge gained this week, rather than posting more photos when I should be queuing at the builders merchant.

 

[vinn]

To explain what you have done so far a photo would help.

Gulley bends cracking in the U-bend position (such as your's) have typically dropped due to a lack of a concrete bed that would have resisted ground movement.

Where would any land drain drain to? Theres no sign of there having been any kind of drain leading away from the gulley?
What would be the purpose of this land drain?
Your gulley grating is set about 120mm too low: the grating should be roughly level with the surrounding ground or patio surface.
The down pipe shoe is discharging across the grating when it should be discharging vertically down into the grating.

 

[amfisted]

I'd love to provide a photo, but unfortunately I buried the evidence this morning.

There was a piece of old breeze block under the gully when I first excavated it, but in the photo its been removed; and there certainly wasn't any concrete. Doubtless that lack of support did contribute to the eventual fracturing of the pipe.

The land drain pipe (the flexible, yellow, perforated plastic stuff, which I know isn't technically known as "land drain") was leaning against the two slots in the bend but was not connected, so most of the water collected will have drained away into the surrounding earth rather than entering the drain. Its purpose was to collect water which is discharged from weep holes in a garden retaining wall, and which ran along a concrete channel to the mouth of the perforated pipe. This function will continue with the new gully, but it should be much more efficient because I've joined the yellow pipe to the gully's second connection via a 90 degree elbow, angled upwards.

The new gully is fitted more or less in the position you recommend, and the downpipe looks to be at the wrong angle because by the time the photo was taken the gully had moved a good way from its original position, all supporting earth having been removed. So all's well, with luck. ;0)