Thames water - email re very high usage!

MrChips

Morning all.  Awoke this morning to an email from Thames Water warning my that my upcoming biannual bill would be higher than usual due to unusually high usage over the last six months.

Naturally this was concerning, and also unexpected as there has been no noticeable change in pattern of water usage which would explain this.  If anything I would expect it to be a little lower as our shower has been broken which has meant less frequent use than previously.

I called Thames Water to clarify the details, but they were unable to be specific as the customer service agent's system wasn't working for her.  She suggested I take a meter reading and then shut off the stopcock for a couple of hours before taking another reading to see if there was a potential issue with the meter or a leak.

Our meter is located at the bottom of a tube under a small plastic cover in the pavement outside our front garden.  I haven't had cause to look at it since moving in over 10 years ago!  Opening the cover, I couldn't actually read the meter as it was buried in sludge/muddy water and the tube seems broadly my arm's length which makes direct access difficult.

If Thames Water are to be believed, they took a reading last week but I struggle to believe they could also have read it without first cleaning it.  Or do they have some other means of doing so (e.g. remotely?).

Either way, having done some more investigation, I can see the meter reading used on our last bill (September 2024) was suspiciously low.  So much so that it was actually lower than the previous estimated readings going back the last few bills, and was implying we'd only used 42 cubic metres of water in 2 years since the last non-estimated reading).  This is for a family of three.

So what seems far more likely is that it's not a high reading this time, but an artificially low reading last time.  Which brings me back to my previous question I think - how are readings taken for a meter such as ours which is buried under the pavement and covered in mud?  Which readings can we actually trust?

Assuming my theory is correct, I wouldn't want to pay for 2.5 years of usage at current rates, but implied usage each six months since August 2022 on the lower rates in force at the time.  I assume I have the right to insist on this?

Thanks for reading this far!

MrChips

Thames Water meter reading history, if it helps:

August 2021: 3695
February 2022: 3786
August 2022: 3831
March 2023: 3881 (estimated)
August 2023: 3919 (estimated)
March 2024: 3973 (estimated)
September 2024: 3873
March 2025: 4134 (bill not come through yet, but I reverse engineered this figure from the amount showing as owing online.  Can't easily access meter to verify)

QrizB

The "average" UK person uses 140 litres of water a day, per the stats. So three average people will use 420 litres a day, 150 cubic metres a year. The period from Aug 21 to Aug 22 was 136 cu.m. so not that far from rlthe average. That would have made Aug 23 something like 3970,  Aug 24 about 4100 and the current reading close to 4200?

My meter is a bit like yours and I take a sponge with me (an old car washing one) so I can bail out the hole and wipe the glass on the meter.

brook_heather

Your September 2024 reading doesn't look right given earlier actual reads - possibly it was misread as it was likely much higher.  If your meter isn't smart then it would need to be manually read and usually this is done every six months.  You will need to scrape away the mud to get an actual reading.  There hasn't been that much change in water unit rates over the past few years - the big increases are coming in April so it would be a good idea to make sure this months reading is accurate.

MrChips

Thanks for the input.  I'll go look for a suitable sponge!

While rates may not have increased too significantly (relative to April 2025) I've worked out that paying for the supposed 261 cubic metres over the last six months at current rates would cost £63 more than if that usage was spread over the period since the August 2022 bill (prorating by days).

Grumpy_chap

I am a bit confused by the OP suggesting they underpaid for past periods.  From the readings (estimated readings) shared, the OP seems to have over paid for water in the period up to March 2024 and then used no water (negative volume) until September 2024.  Subsequently, paying the rate as per metered consumption.  The result would be that the OP had more water at the lower pre-March 2024 rates than the higher post-September 2024 rates.

MrChips

I don't follow your logic Grumpy_chap - although maybe it's due to me not explaining myself well.

As things stand I'm being charged for using 42 cubic metres between August 2022 and September 2024 when rates were generally lower than they are now, and 261 cubic metres in the last six months when rates are at a historical peak.

This will be more expensive than if the total 303 cubic metres was spread out so more was used in the previous, cheaper, years.

What I didn't previously mention was that my September 2024 bill (only opened today!) included a reworking of my bills since the last non-estimated reading so that's possibly where your confusion arose.

MrChips

Update:

With the help of a good sponge, I managed to clear the excess water from the bottom of the tube and confirm the accuracy of the latest meter reading (4134 in mid March 2025).

I got in touch with Thames Water and received a revised bill on Friday.  However, they still haven't properly prorated the use between the two confirmed readings (ignoring the erroneous one in September 2024).  It's not clear what approach they've taken to allocate usage, but they've got me only using 11 cubic meters from August 2022 to March 2023, 139 cubic metres the following 12 months (to March 2024), and 152 the year after that (to March 2025).  By weighting the usage to the later years, they are overcharging me.

I've gone back again to ask them to have another go...