Detecting an underground water leak

[pulck]

I've been advised by Thames Water that I probably have a water leak somewhere on my property. They have given me 4 weeks to fix it or else they say they will have to do it themselves and they will charge me for it.

It's strange, though, because the water meter shows consistent/normal readings, apart from for 4 days in November 2023, when water usage went up to around 10K litres per day and then dropped back down to normal without any intervention. Does this sound like a leak? I asked if it could've been a smart meter issue but they said, no, it's a leak (without any explanation of how they determined that).

If it is a leak, what is the best way for me to detect it? Are there leak specialists who can locate it (or even determine if there is one) without digging up the front garden, etc.?

 

[oldbuffer]

1. Locate your internal stop tap, fitting a new one if necessary.
2. Turn off the water to your property using the internal stop tap. Make a note of the meter readings at the same time.
3. Leave water off for as long as possible. (Or repeat exercise).
4. Before turning the internal stop tap back on, make a note of the meter reading.
5. If the meter reading doesn't change between your turning the water off and back on again, you do not have a leak.

 

[pulck]

1. Locate your internal stop tap, fitting a new one if necessary.
2. Turn off the water to your property using the internal stop tap. Make a note of the meter readings at the same time.
3. Leave water off for as long as possible. (Or repeat exercise).
4. Before turning the internal stop tap back on, make a note of the meter reading.
5. If the meter reading doesn't change between your turning the water off and back on again, you do not have a leak.

Thank you. Yes, that makes perfect sense. I may have to get an internal stop tap installed but it'd useful anyway.

There's no way a smart meter could mess up this test, is there?

 

[bernardgreen]

around 10K litres per day

The average 9m x 4m pool will contain about 61,200 litres

Does one of you neighbours have a swimming pool and access to your water supply ?

 

[pulck]

Does one of you neighbours have a swimming pool and access to your water supply ?

If they have, they've kept it well hidden

 

[pulck]

Does one of you neighbours have a swimming pool and access to your water supply ?

You jest but it has raised an interesting question.

Is it possible for 10K litres of water to be leaked into my property daily for 4 days without my noticing? Would there be major subsidence, or is that not enough to cause that?

 

[bernardgreen]

10,000 litres per day for just 4 days then back to normal suggest ( to me ) that the "leak" is a controlled leak and not a genuine leaky pipe.

 

[pulck]

10,000 litres per day for just 4 days then back to normal suggest ( to me ) that the "leak" is a controlled leak and not a genuine leaky pipe.

What things could cause a controlled leak?

I genuinely don't think any neighbours stole our water. We live in a terrace and are on good terms with everyone!

Is there anything Thames could've done to cause this?

 

[gas112]

10K Leak for 4 days then nothing a leak that big under ground does not seal itself
approx 7 litres a minute any chance an outside tap was not turned off properly or a syphon faulty on a toilet not used regularly and not shutting off properly so water constantly running into the bowl
but do as old buffer suggests .
Very strange they are contacting you 10 or so months later on a 4 day reading from back then

 

[Notch7]

and they will charge me for it

Be careful, Thames water might charge you £15.2b

 

[pulck]

10K Leak for 4 days then nothing a leak that big under ground does not seal itself
approx 7 litres a minute any chance an outside tap was not turned off properly or a syphon faulty on a toilet not used regularly and not shutting off properly so water constantly running into the bowl
but do as old buffer suggests .
Very strange they are contacting you 10 or so months later on a 4 day reading from back then

I would've known, I think, if I'd left something running for 4 days. They didn't contact me, they just doubled my bill. I contacted them and said can you check the meter. That's when they said I had a leak (as I say, 4 days long last November)

 

[oldbuffer]

Could it be a previously mis-read meter?

 

[pulck]

Could it be a previously mis-read meter?

Thames are insisting the meter is correct. It was already a smart meter at that time

 

[Murdochcat]

A smart meter. Hum

Do you check your bills and the readings started to your actual readings?

Surely the first thing to do is take weekly or daily readings for a period

 

[pulck]

A smart meter. Hum

Do you check your bills and the readings started to your actual readings?

Surely the first thing to do is take weekly or daily readings for a period

I haven't done that. Can I still even take an 'actual' reading if there's a smart meter installed?

In any case, I have now only a few weeks to fix the leak (or establish there isn't one) before Thames insist on fixing it themselves (see my earlier post).