Mis‑Metering, Suspected Leak, Unnecessary Pipe Replacement

DickyRobbo44

I recently switched from an unmetered (rateable value) supply to a metered supply with Severn Trent. Three months later, I received a very high bill, so I followed their leak‑diagnosis steps.

 

1. Initial Leak Diagnosis

- My external meter (in the pavement) showed high usage and the leak indicator was spinning.

- I isolated my internal stop tap, but the meter still advanced.

- Severn Trent’s billing team told me this indicated a leak on my private supply pipe.

- Based on this, I contacted a Severn Trent–approved WIAPS plumber.

 

2. Plumber’s Assessment

- Plumber attended and said he could hear a “small leak” on my old lead supply pipe.

- He recommended a full replacement of the 23m supply line.

- I agreed, assuming the diagnosis was correct.

 

3. Pipe Replacement & Discovery of a Shared Supply

- The plumber replaced the entire supply line.

- As they were backfilling, a neighbour a few doors down reported their water had gone off.

- It turned out the supply was shared between several houses.

- My old lead pipe was not leaking.

- The plumber had to dig again, reconnect the shared supply, and cap off my old pipe.

 

4. The Real Problem Identified

- The reason the leak indicator was spinning was because Severn Trent had installed my meter on a shared supply, even though the other houses all have internal meters.

- So my meter was measuring everyone’s usage, not just mine.

- This made it look like I had a leak when I didn’t.

 

5. Severn Trent’s Response So Far

- Over the phone, Severn Trent have already admitted the meter appears to be incorrectly fitted.

- An engineer is visiting to formally confirm this.

- They have temporarily reduced my direct debit.

- They have said I can apply for a free lead‑replacement connection (which would put me on my own supply).

 

6. Current Situation

- I now have a brand‑new 32mm MDPE supply pipe that I didn’t actually need.

- The plumber has issued the invoice and needs to return to expose the connection again so Severn Trent can connect the new line.

- I’m unsure who is liable for the cost:

  - Severn Trent (for mis‑metering and causing the false diagnosis)

  - The plumber (for not identifying the shared supply)

  - Or me (for acting on incorrect information)

 

7. What I’m Trying to Decide

- Should I pay the plumber in full?

- Should I wait for Severn Trent’s formal findings?

- Should I challenge the plumber for misdiagnosis?

- Should I ask Severn Trent for compensation for unnecessary work?

michael1234

I'm not a plumber but I do a lot of development and a fair amount of plumbing work.

My thoughts are I can't see why the plumber is to blame. The evidence presented had all the signs of an external leak and presumably that is what he told. Unless you very clearly asked his quote to include an investigation as to the pipe layout I can't see it being his fault ?

The water company definitely need to re-imburse you for all your neighbour's water that has been charged to you. Perhaps you could ask your neighbours for as many readings from them as possible? Even if they don't have thne exact dates, you might get a rough idea of their consumption to help ensure Severn Trent don't overcharge you.

As for the unncessary work. Well I suppose the only good news in all this is the bypassing of the lead pipe. But I think (I don't know) that ultimately if you asked a plumber to do some work based on a false assessment of the plumbing layout on your property then maybe you should shoulder some of that liability? Either way, I'd definitely be paying the plumber with a view to perhaps getting some reimbursement (50:50 ?) from the water company.

casper_gutman

I'd have thought Severn Trent ought to be responsible for your costs. They kicked it all off by installing the meter incorrectly, then inaccurately advised you that there was a leak on your private pipe when (i) the pipe wasn't private and (ii) there wasn't a leak. Of course, getting them to accept their responsibility - or obtaining and enforcing a legal judgement against them if they don't - may be another matter. Hope you kept good records of all the communications you had with them!

casper_gutman

In terms of the plumber's responsibility, I'm not quite sure how they could replace the whole supply line without noting that - presumably - there was at least one branch off it for supplying the neighbours. Possibly they bear some responsibility there?

DickyRobbo44

The plumber is asking me to pay the invoice, is there any reason I shouldn't? Like it has been said I asked for a service and it has been given, I just don't want to lose any bargaining power.

Section62

https://forums.moneysavingexpert.com/discussion/comment/81935628#Comment_81935628

Replacing the supply pipe wouldn't necessarily mean exposing the whole of the old pipe and therefore being able to see branches to the neighbours. Usually you'd only dig as much as you need to, and not necessarily on the same line as the old pipe. Strictly all that was necessary was to locate and remove (a section of) the old pipe at the meter connection.

Personally - knowing the value of scrap lead - I might have done a little bit more digging to be able to extract the old pipe, but for a professional plumber it isn't likely to be cost effective to do so.

Section62

4. The Real Problem Identified

- The reason the leak indicator was spinning was because Severn Trent had installed my meter on a shared supply, even though the other houses all have internal meters.

- So my meter was measuring everyone’s usage, not just mine.

- This made it look like I had a leak when I didn’t.

Observing the meter spinning should have given a clue that the meter was serving more than one property - the rate of spin would vary as and when the neighbours were using water, whereas a leak alone would normally result in a relatively constant flow rate. Unless the neighbours were very frugal with their water use, the volume being used should have rung an alarm bell with Severn Trent that there was something more than a leak going on.

The plumber hearing a “small leak” wasn't necessarily a misdiagnosis. It isn't easy to differentiate between a small leak and some parasitic flow, and it remains possible the old lead pipe did have a small leak, in addition to also supplying the neighbours.

I'd suggest paying the plumber's bill - you need their further help, and it would be difficult to prove they were in the wrong.

casper_gutman

https://forums.moneysavingexpert.com/discussion/comment/81935698#Comment_81935698

Good point. My plumber and electrician are both loath to get involved in digging at all, and the guy who unblocked our drain mentioned he has an arrangement with a friend with a landscaping company to provide labour for trenching (and more to the point presumably for the potentially more lucrative reinstatement!).

plumb1_2

Years ago most utilities companies had a team going around in the dead of night to locate leaking buried mains water pipes. Excellent service, they usually would pinpoint a leak within a meter.

The vast majority of plumbers wouldn’t entertain digging for a new main, they would subcontract it out. Most replacement of mains is done by using a Mole. And just digging to make the final connections.

Pay the plumber has he’s done as requested.