Water supply leak - underground. How to locate it?

[MeldrewsMate]

I very important customer of mine, the landlord of my local boozer, complained of a continuous noise coming from the pipework of the pub, even when he turns off the mains stopcock. It stopped when I turned off the supply at the water meter, so I determined there is a leak underground between the meter and the stopcock.
The rate of loss is about 10 litres per minute, or 14 cubic metres per day, about £40!

The space between the meter and stopcock is built-over with his beer cellar, and there are drains under the concrete floor.

Can anyone put me in touch with a specialist in locating the leak, so we can dig and repair with the minimum of disruption? The site is near High Wycombe, darn sarf.

If not, can anyone suggest an alternative to digging in a new mains pipe with a run of about 10 metres?

PS The stopcock works, and stops water to the whole pub!

MM

 

[Ian H]

I do this for a living.

First thing I would do is see what material the pipe is. If metal I could clamp on and then locate the line of the pipe and use a listening stick to try and find the leak.

If I couldn’t do that i’d pick the easiest place to dig into the pipe, open it up and put an inflatable leak detector or Pipe Mic into it to find the leak.

Other things I might do if I didn’t have the kit would be see if any water was flowing down the drain when it shouldn’t be, make sure there are no possible shares or T’s off the pipe to an outbuilding or something.

 

[HERTS P&D]

Mole a new water main into the cellar.

Found these on a goggle search, give them a call:

http://www.ems-watermains.co.uk/mol...MI142vtqGB3wIVEeJ3Ch0RCQSAEAAYAyAAEgK5A_D_BwE

Andy

 

[Diyisfun]

If he is on a water meter, report the leak, they will send someone & confirm. When it is fixed he will not be charged for the lost water. Happened to me this year. I had to lay new pipe.

 

[MeldrewsMate]

...First thing I would do is see what material the pipe is. If metal I could clamp on and then locate the line of the pipe and use a listening stick to try and find the leak.

It's 15mm copper where it comes out of the floor in the gents' crapper, but as there's an external water meter in the street I assume that bit is plastic, because if the copper went all the way to the meter and the leak was anywhere near the meter the hole that it's in would tend to fill up.
Ian H, could your listening stick locate the noise from the leak in a noisy environment (road noise outside, chillers running inside, etc)?
And to what precision?

...make sure there are no possible shares or T’s off the pipe to an outbuilding or something

Good point, there is one possible place I didn't check, will do so before calling in someone like you? What qualifications should I expect a leak finder to have, and what kit should they have?

Mole a new water main into the cellar....Andy

There are drains under the 'cellar', which is not a cellar, it's on the ground floor.

If he is on a water meter, report the leak, they will send someone & confirm. When it is fixed he will not be charged for the lost water.

Thanks for that; useful to know, especially at the rate the water appears to be disappearing ~£40 per day!
Update...just phoned landlord, and he's already reported the leak.

 

[Ian H]

Ian H, could your listening stick locate the noise from the leak in a noisy environment (road noise outside, chillers running inside, etc)?
And to what precision?

Good point, there is one possible place I didn't check, will do so before calling in someone like you? What qualifications should I expect a leak finder to have, and what kit should they have?

It all depends on the leak. Some small ones can be very noisy and some big ones are very quiet. It all depends on the pipe type and the way the waters escaping it.

I only have the basic EUSR National Water Hygene card as a formal qualification but i’d say experience is worth more than anything else.

Equipment wise the minimum I would expect would be a listening stick (digital or old school) and the gear to dig a hole through any surface.

 

[MeldrewsMate]

Thanks to all. Off for some scran now.

 

[Ian H]

Have a read of this next time you’re on the toilet:

https://www.diynot.com/diy/threads/leak-finding-on-domestic-water-supplys.475493/

 

[KenGMac]

MeldrewsMate,

I am with last post OK long but could be just what you need?

As an aside, your client could make an Insurance claim under 2 headings.

1/. An escape of water from underground services [Insurer should pay for tracing the exact point of the leak --- then use Ian H above???]
+
2/. Reclaim cost of escaped water.

Ken.