We have installed a number of meters across our region, to show how much water goes into each area.

These tell us which areas have higher numbers of leaks and burst mains, so we can fix the worst affected areas first.

This work involves replacing old, worn-out water pipes.

We are often able to avoid digging trenches, by pushing a new pipe inside the old one. This means less disruption for residents, businesses and road users.

Yes.

London's water mains are among the the oldest in the UK, with 44 per cent over 100 years old.

We apologise for the unavoidable disruption our main replacement works causes.

Customers will in the long term, as the more old pipes we replace now, the fewer burst mains, leaks and disruption there will be in the future.

Each area we work in will be different, but we would expect a typical saving to be about one million litres of water per day for each area, once the work is complete.

We write to local residents before we start work, 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, you can get up-to-date information on our work in your area by searching our map - www.thameswater.co.uk/live.

The information on our Victorian mains replacement work is updated every Monday.

We aim to keep any disruption to a minimum, but we will consider claims for compensation and look at each case individually.

If any customers are likely to be without water for four hours or longer, we will write to them at least 48 hours before we turn they water off.

The letter will give details of when we will turn the water off, when it should come back on, and how customers can find alternative supplies in the meantime, eg bottled water.

We also always try to tell customers if their water will be off for a shorter period of time.

We aim to turn the water back on within a maximum of 12 hours.

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 we replace the water main with 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.

No, although there may be a need to visit your property.

Customers should always ask for proof of identity, and can ring our 24-hour Customer Centre on 0845 9200 800 (Textphone: 0845 7200 899) to check.

We also run a doorstep password scheme, to stop 'bogus callers' - who often pretend to be from your water, gas or telephone company - from gaining entry into your home under false pretences.

Unfortunately, we may need to make some areas unavailable for parking for a short period of time, but we do our best keep this to a minimum.

We have so far invested over £650m in improving London's water mains.

As well as our planned work to replace ageing water mains, we also continue to fix leaks and bursts as and when they happen.

On average, we fix a leak every eight-and-a-half minutes.

• Find out more about how we are tackling leakage

The meters will give us a much better idea of when and how often our customers use water, and will also show how much water is leaking from customers' privately-owned pipework.

We work closely with other utility companies whenever we can.

This way, we can often halve the disruption caused, particularly during diversions, road closures and parking suspensions.