how to save water

Your bill and our charges

Leakage responsibilities, allowances and costs

Leakage on water supply pipes can be a problem for all of us.

Depending where a leak occurs on the water pipe it can affect one or many customers through reduced water pressure, property damage, repair costs, and potentially increased bills.

There are some steps we can all take to prevent leakage, but when it happens it is important to understand what your responsibilities are, and what costs you are liable for, or allowances you may be entitled to.

As always though, prevention is better than cure so please take precautions against leakage, especially in cold weather.
Remember when water freezes it expands, and that can cause pipes to split and crack. The following steps can help:

  • Make sure pipes are deep enough in the ground. A water supply pipe should be at a depth of 750mm (2½ feet) from the surface. This can protect it from accidental damage from ploughing or digging the ground, or from freezing in cold weather.
  • Insulate all exposed pipework. This will help slow down any freezing in prolonged cold weather.
  • Fit stop tap on supplies that you know you won’t be using for long periods so you can drain the pipes when they are not in use. Place these on your section of the supply pipe as close as possible to the boundary.
  • Fix any drips or slow leaks you know about. A slow run of water freezes faster than still water in a pipe because of the way the ice builds up. Keeping a tap running slowly will show if you still have a water supply, but it is wasting water, and it can just make things worse.

There is a leak on the pipe supplying water to my home or business; who is responsible for fixing it?

It depends where the leak occurs. The simple diagram below illustrates which part of the pipe is the responsibility of NIW and which is yours as the customer.

Pipe responsibilities single supply

You can download an information and advice leaflet on What to do next when you suspect a leak depending on whether your supply is in an agricultural or business setting.  

Agricultural Setting

Business Setting

Regardless of where the stop tap is installed once the pipe enters your property you are responsible for maintaining it. Anything on the public side of the boundary is up to us to look after. This means you are also responsible for any leakage on your section of pipe. Once you become aware that you have a leak, you must take steps to repair it. If you don’t you could be wasting water, and if we know about it we can serve a legal notice on you requiring you to make the repair. A cracked or damaged pipe can lose thousands of litres of water per day.

If you do not own your property, your landlord may be responsible for fixing the leak, but the bill payer will still be liable, even if the leak is on a shared supply pipe within the property. If necessary you should ask your landlord, or the property owner to carry out the repair.

What will I have to pay for?

If the leak is on a section of pipe that is your responsibility then you will have to pay for the repair.

If the leak occurred on a section of pipe that is our responsibility to look after, or it is as a result of damage caused by us or our contractors, we will repair it and you will not have to pay any additional costs because of water that leaked.

If you are a domestic customer you do not have to pay for any water lost through the leak.

If you are a metered non-domestic customer you will also have to pay for all water supplied through the meter. If you do not tell us that the water leaked, we will also charge you for sewerage based on all the water measured by the meter.

Can I get my bill reduced? (measured customers only)

Under some circumstances we can reduce the amount on your bill. However this depends on where the leak occurred and how quickly it was dealt with.

In order for us to review your account following a leak on your supply, you must apply for a Leakage Allowance. Depending on the location of the leak within your property and what your supply serves, you may be entitled to a reduction on your bill. In order for us to review your account, you must complete a Leakage Questionnaire. This is available by calling us on Waterline 03457 440088, or Billing Line 03458 770030. Alternatively you can download a copy of the form and return it to us by post or by email:

Leakage Allowance Application Form


Northern Ireland Water
PO Box 1026

Email: customer[DOT]billing[AT]niwater[DOT]com

Can't find what you're looking for? Visit the Need our Help section