Slow water leak

JohnB47

Just looking for advice on the next step - having exausted all indoor possiblilties.

I've just received the quarterly bill from South West Water and it shows we used over twice the amount of water compared to usual, and compared to the same quarter as last year.

I looked at the water meter out on the path and the little cogged wheel was turning slowly. Did some calculations and it seems there's approx 1.4 litres of water per hour going somewhere. I turned the water off at the meter and the wheel stops turning.

So I've done everything needed to check for a leak indoors. Checked under all fittings first (sinks, rear of loo/cystern. Isolated the loo cystern after checking for a small leak down the bowl (which I've fixed twice in recent years so I know what to look for). Didn't look under the bath actually but read on. Looked up at all ceilings, looked under the kitchen units and I can see the main water pipe coming into the house - no sign of damp near that pipe or anywhere on the floor in there.

There is a tee piece off this pipe to supply an outside tap and unfortunately this is before the stop valve. I had replaced that outside tap last summer and never finished the brickwork around it, so I can easily see that there's no moisture anywhere on that fitting. I can't see the pipework inboard though. The pipe goes through the cavity wall, tees into the cold water feed pipe running between the back of the kitchen units and the inner wall. I can't see that tee piece or the pipework but as I say, the floor under that whole are is bone dry.

I managed, after quite a struggle, to get the stop valve under the kitchen sink to turn off. What a design! Opened all taps, shower etc and let the house drain down to a drip evey now and then. The meter wheel still turns at the same rate.

So what to do? It seem's there is a leak between the meter and the house (up a driveway - no recent building work done).

Looks like a call to South West Water next - but what should I expect them to do or advise?

Thanks.

MyRealNameToo

Turn off the internal stopcock, check taps no longer run and then check the meter, is it still spinning? If it is then the leak is between the meter and it coming into your home, if it stops then the leak is inside of your property.

Given its post the meter its almost certainly your problem and so not something the waterboard will get involved in.

JohnB47

https://forums.moneysavingexpert.com/discussion/comment/82004778#Comment_82004778

Thanks.

Yes, meter wheel still spinning when stop valve turned off under the kitchen sink. Looks ominous.

So, is it down to me to find someone (a plumber - who else?) to try better methods than I have to positively say that the leak is underground between meter and house. Are there better methods? Some sort of device that can pinpoint the area of an underground leak before digging up? Or is that fanciful?

Albermarle

Presumably there is no sign of water around the meter, as where your pipe joins the meter can be a trouble spot sometimes.?

stuart45

https://forums.moneysavingexpert.com/discussion/comment/82004795#Comment_82004795

Listening devices specifically designed for underground water leaks.

EssexExile

https://www.originalleakdetective.co.uk/

MyRealNameToo

https://forums.moneysavingexpert.com/discussion/comment/82004795#Comment_82004795

Where is the stopcock in the house compared with the meter? In our old property it would be much better, the stopcock was on the inside of the front wall, the meter on the edge of the property directly opposite so the pipe was a straight line under some lawn. In our last property it was on the other side of the property so the pipe was travelling under the property so access could be more complex.

Sometimes you can easily spot where the leak is even if it's underground… the dry parched front lawn that has one patch of very lush green grass on a direct line from meter to stopcock. Plumbers can use specialist equipment to try and find it depend on the material of the supply pipe and its depth will determine which are likely to be the most successful. It gets more complex if it passes under the property.

Trying to trace an internal leak can be much worse, have seen trace and access claims on insurance for £50k+ for internal leaks but depends on a range of factors.

JohnB47

Thanks everyone. The soil under the meter is moist, just that, but then it’s been raining. Not conclusive really. Could be leaking at the inboard meter joint but I’m not sure how I would check that. I’m getting fed up bending over!

The meter is on the footpath, then there’s a paved (with sets) drive, then large clippings along the side of the house, with presumably the pipe running underneath. The mains comes up in the corner of the kitchen, at the rear of the house. Can’t spot any dampness in the house anywhere, although I’ve just realised that I haven’t checked the cupboard under the wall mounted boiler. Will do that tomorrow.

I’ve just spoken to South West Water and was impressed. They gave a website to help find a suitable company to find the leak and suggested I could claim a refund on the wasted water and some payment towards the cost of fixing. They’ve also paused the auto payment (we pay in full each quarter).

I’ll have a look at the links suggested.

WIAWSNB

Very frustrating situation, John. Compounded by the slow rate of leak - 1.4lph is (Googles...) just a fastish tap drip rate, of around one to two drips per second.

Is a stethoscope going to detect this flow rate? I don't know, but it seems unlikely.

Although seemingly unlikely, you haven't been able to fully discount it being in the garden tap run, and this tee is clearly in the wrong place anyway. Soooo, any mileage in first correcting that issue, and fitting an easy-to-use mains stop valve at the same time? I'd personally go for a full bore lever ball valve these days - very unlikely to seize (SS ball in a nylon sleeve), and offski in a second.

Depending on access, this would be a simple job for a plumber (or DIYer), and it sounds as tho' it would be a good move anyway?

Worth considering? You'll then know where the leak is, to an extent...

We have a dry warm spell coming up, so that might be a pointer if the area around the meter remains damp. Even tho' you are responsible for your side, I think the WB would be if it's their poor connection to your pipe?

When you call up the detectorists, ask if they can trace such a small flow.

Where, along the underground run, can you dig?! What 'path' surrounds the meter, yours or public? What material - tarmac or gravel?

And do you have leak detection included in your household policy? If not, it sounds as tho' it's either hand it over to the pros, it start making test holes yourself.

Is the mains pipe to your house plastic? No chance it's old lead? If lead, then perhaps it's time for a new pipe to be moled?

Green_hopeful

there are ways to find leaks underground. I like the gas one where they fill your waterpipe with gas and look for the gas escaping from the pipe. It can be detected through tarmac and concrete. Probably overkill for your problem. I hope you find it.

p00hsticks

When my father had a slow water leak in the driveway, you could actually hear a hissing sound as the water escaped through a small hole in the pipe - but I suspect it was a bigger leak that the OP's.s