How to fix a water pipe without turning off the water

[TheBarkers]

I've got a pipe, approximately 75mm o.d. plastic with a hole in it. The problem is no-one knows where the stop cock is and chances are that it's been fenced off with no way for us (or Thames Water) to access it.

Does anyone know of a way of fixing a pipe this size without turning off the water?

Kat

 

[Agile]

If its mains water then Thames Water contractors can often do it but they can get very wet and thats not nice if the water is cold.

One method they use if the pipe is blue plastic is to squeese it flat but I dont know if they can do that safely with such a large pipe without risking splitting it.

In theory it can be frozen but it would be very unusual for a firm to have that equipment. It also needs virtually no flow otherwise it cannot be frozen.

If its only a small hole then a bodge repair can be made with a rubber patch and a clamp.

Best of luck, I expect you will need help from TW or their contractors.

Is it on a farm?

Is it metered and are you paying for the lost water?

Tony

 

[TheBarkers]

I've tried freezing a smaller pipe before using a freeze spray but it didn't work very well. Might a proper contractor have better equipment to freeze larger pipes?

The pipe is black and feels pretty rigid so I don't think squeezing it would work.

The hole is probably about the size of a 50p piece and part of the plastic pipe has been pulled up so the surface of the pipe isn't flat.

It's not on a farm and I'm not sure if it's metered or not. I assume it is, which means we've racked up a fair bill for the water lost. I don't know whose responsible if TW can't find their own stop cock and someone else has put a fence around the manhole access.

Thanks for the advice.

 

[Agile]

Surely you know if its metered and where the meter is?

Is the leak on land you own?

How did the damage occur?

A big mains leak can lose several thousands of pounds of water each week!

They have a powerful clamp for squeezing plastic pipe.

This all sounds very odd. Water mains pipe must be laid at least 750 mm deep!

Were you having fonds dug by machine?

Tony

 

[StephenW]

From a layman's point of view, if you've got a 3 inch diameter pipe with a hole the size of a 50p piece then are you sure it's mains? You'd have a pretty hefty fountain or, if the hole is pointing downwards, a very waterlogged bit of ground.

 

[Agile]

Manual squeeze tools are available for pipes up to 90mm and to 125mm.

Hydraulic tools are used for larger pipes.

Commonly used in the water and gas industry!

Larger pipes need a re-rounding tool afterwards!

Luckily I have never needed to do of that kind of work!

More answers please.

Tony

 

[TheBarkers]

Thankfully the pipe is set in gravel/ballast so the water drains away.

The pipe's about 0.6m down. The pipe was caught by a tooth on a JCB bucket. The service plans we had didn't show it and the CAT didn't pick it up, obviously, because it's plastic.

I've had a look on the internet and there seem to be a few tape/resin type products that can wrap around the pipe and then set solid. They claim to work underwater too.

 

[Nige F]

It`s not positive pessure from a sewage pumping station is it . Black pipe set in gravel , not on supply plans

 

[TheBarkers]

Ha ha, I hope not. The water is clear, doesn't smell and I've had my raggedy hands in it up to my elbows and I feel fine.

I think I might try this DuraPower tape stuff. It seems about the only thing that might work.

Any other suggestions?

 

[flameport]

Any other suggestions?

LLFA compression tape.

 

[DaleRCL]

You may be able to get a company to come and freeze it with nitrogen. But even then you will still have to cut the pipe and find a fitting to repair it with once you have removed the damaged section.

 

[Agile]

If its mains water at the usual minimum pressure then a hole 20 mm diameter would send a jet into the air about 2-3m or higher!

Was this your JCB digging on someone else's land?

Tony