Frequently asked questions
This page offers answers to the most frequently asked questions about our Victorian mains replacement work.
Why has Thames Water chosen these areas?
We have installed a system of meters across our region, showing how much water enters each 'zone'.
These indicate which areas have higher numbers of leaks and burst mains, so we can fix the worst affected areas first.
What will the pipe replacement work involve?
This work involves replacing old, worn-out water pipes. We are often able to avoid digging trenches, by inserting a new pipe within the original one. This results in less disruption for residents, businesses and road users.
Are the pipes being replaced because they are too old?
Yes. Around 12 per cent of London's water mains are over 150 years old - among the oldest in the UK - and more than 40 per cent are over 100 years old.
How will customers benefit?
Our work causes unavoidable disruption, for which we apologise, but we'd urge people to bear in mind that they will benefit in the long term.
The more old pipes we replace now, the fewer burst mains, leaks and disruption there will be in the future.
By how much will leakage be reduced?
Each area differs, but we would expect a typical saving to be about one million litres per day for each of the zones in which we complete this work.
How are local residents kept informed?
We write to residents before work begins, inviting them to drop-in sessions where they can find out more.
Local press, councillors and MPs are also updated on our plans. In addition, we have a hotline number and our website contains up-to-date information on our work, including a search tool which is updated weekly.
Will local traders be compensated for loss of business?
We aim to minimise disruption, but we have processes in place for dealing with such claims, and look at each case on its merits.
Will customers be warned if their water supplies are affected?
If any residents / businesses are likely to be without water for four hours or longer, we will write to them at least 48 hours (residential customers) or 72 hours (commercial customers) before their supplies are affected.
The letter will give details of when the water will go off, when it should come back on, and how customers can find alternative supplies in the meantime.
We also always try to tell customers if their water will be off for a shorter period of time.
How long will customers be without water?
We aim to reconnect customers within a maximum of 12 hours.
Will my 'earthing' be affected by these works?
Some properties' electrical appliances are earthed via the water main, which is often made of cast iron - this will no longer be the case if the main is replaced by one made of plastic. Read more about electrical earthing.
We send a leaflet to customers affected by our work, advising them to get their earthing checked by an electrician.
Will Thames Water staff or contractors need to work inside people's homes?
No, although there may be a need to visit your property.
As ever, customers should ask for proof of identity if needed, and can ring our 24-hour Customer Centre on 0845 9200 800 (Minicom or Typetalk: 0845 7200 898) to check.
We also run a password scheme, details of which are available on the number above.
Will local residents still be able to park in the street?
Unfortunately, some parking suspensions may be unavoidable for a short period of time, but we do our best to minimise this.
How much is the work costing?
We have so far invested over £650million in improving London's water mains.
What else is Thames Water doing to stop leakage?
As well as our planned work to replace ageing water mains, we also continue to fix leaks and bursts as and when they occur. On average, we fix a leak every eight-and-a-half minutes.
Why are you installing water meters as part of the work?
The meters will give us a much better idea of patterns of water usage, and will show how much leakage comes from privately-owned pipework.
Can Thames Water work jointly with other utilities to minimise disruption?
When practical, we work closely with other utility companies. This way, we can often halve the disruption caused, particularly during diversions, road closures and parking suspensions.
