How are we tackling leakage?

We try our best to repair leaks on our network as soon as we find them.

  • Our Leakage Team detect an average of 30 leaks each month (unreported and invisible leaks)

We actively encourage customers to repair leaks on their service pipes when we detect them. We do this by giving them advice and helping them to find the leaks at their properties. In some cases we use enforcement action and the powers that we have if a customer is wasting water through leakage and refuses to repair their leaks. On average 30% of detected leaks per month is of a private nature. 

Whenever the Department of Infrastructure are undertaking road relaying/reconstruction we take the opportunity to replace the water mains at the same time.

We have a scheme to install 19 Pressure Management Valves (PMVs) in the network, aiming to manage pressures in the system. Reducing pressures reduces leakage and bursts. We have to do this whilst still meeting customer expectations for water pressures. Find out more about pressure management.

In the last 3 years, our Leakage Team has increased from 3 to 5 engineers and we have improved our leakage equipment and technology, and doubled the area that we can cover. This includes adding specialist microphones to the network which listen for leaks, using AI software to learn the network, upgrading our pressure sensors and logging devices, and establishing a training facility for our Leakage and Networks staff. 

  • Looking at the 2021-2023 financial year leakage figures, our Leakage Team has managed to reduce leakage by approximately 19.2%

You can help us find leaks and save water. If you spot a leak, please let us know

If you spot a leak or see water bubbling out of the ground it may be a burst main, please call us on 687687 to let us know or you can report a leak online; select 'Mains Water Leak (in garden, pavement, street etc)'.

Having leaks reported to us helps and we are always grateful for your call. The earlier we know about a leak the earlier we can fix the problem before it disrupts your supply.

You can also save water in your home by using water wisely and prevent leaks and bursts by protecting your pipes in winter to stop them bursting.

Leaks are where water is escaping slowly but the pipe continues to supply water. Examples include leaking hydrants, boundary boxes and supply pipes. Leakage repairs are not usually as urgent as burst main repairs because customers will often have water, but it is always helpful to report leaks to us so we can assess them and arrange repairs to reduce leakage in the water network. 

Bursts are complete pipe failures where immediate repair is necessary to prevent customers being without water.

If you find a suspected burst water main please report it immediately by calling us on 687687. 

Leakage is lost water – that’s all the water not making its way to customers. Most of this water leaks from ageing pipes, but because we do not meter domestic properties it is impossible to accurately determine how much water customers are using.

Leaks are caused by various things, including:

  • Old or weak pipes
  • Natural wear and tear on pipes
  • Sudden heavy traffic causing movement in the ground
  • Temperature changes, which cause pipes to swell and shrink
  • High pressure or sudden changes in pressure
  • Extreme weather events, like freeze-thaws.

Leaks from customers pipes

If you can hear water moving through the pipes at night, you could well have a leaky joint. This can damage your property, or lead to contamination of your water supply. Other signs include damp or discoloured patches and mould on walls, ceilings or carpets. If you suspect a leak inside your home, you should contact a registered plumber.

If there is a leak from the service pipe into your home, you may well see a damp patch appearing on the ground, or flowers and areas of grass doing rather better than those around them, especially in dry weather. If you suspect a leak outside your home, you should contact a registered plumber.

Leaks from our pipes

It is believed that 95% of leaks are never seen by customers. They’re often smaller, underground and harder to find. Visible leaks – the ones that do reach the surface – are larger, but they don’t lose as much water. This is because they’re reported to us and we start to fix them soon after they appear. If you think you’ve found a leak please let us know by calling us on 687687 or you can report a leak online; select 'Mains Water Leak (in garden, pavement, street etc)'.

If you notice that the external stop tap or boundary box is broken or leaking please get in touch as above; we will take your details and an experienced member of our team will inspect the stop tap and then arrange a repair.


  • turn off the water at the internal stop tap*
  • switch off the central heating and any other water heating installations at the same time to avoid further damage, or even an explosion
  • open all taps to drain the system
  • call for a registered plumber who should be able to isolate the supply
  • if water is coming through the ceiling, collect it in buckets. If the ceiling starts to bulge, pierce the plaster with a nail or screw to let the water through - ensuring a bucket is underneath
  • if your wiring or any electrical appliances have been affected, do not touch them until they have been checked by a qualified electrician. If in doubt, turn off your electricity at the mains
  • If the plumber needs to turn the external stop tap off we can assist with this. Contact us on (01624) 687687

*Your internal stop tap can turn on or off the main water supply to your home, so in the event of a leak you can shut off the supply quickly. The internal stop tap is generally found where the service pipe enters your home. In most instances, this will be under your kitchen sink. Once you have found it, check that it works; clockwise for off, anticlockwise for on. If it's hard to turn, don't try to force it. If it is seized or broken, it should be repaired by a plumber. To prevent a stop tap from seizing, close and open it once or twice a year.

Leakage measurement is an estimate.

Because we do not meter domestic properties it is impossible to accurately determine the exact amount of leakage that we have. We know how much water we put into the system but we do not (and cannot possibly) know what goes out. We use an industry standard method for estimating leakage and this method is used as a performance indicator for us and allows us to compare our performance. The method basically relies on us measuring the lowest flow into the system each 24 hours and subtracting from that number an industry estimate of what average customer usage would be at that time. The method that we use currently reports that our leakage average is 145 litres/property/day in the 2023 financial year. It must be noted that our leakage figure includes losses on our customers own service pipes and plumbing as well as from our own pipes. So if someone has a dripping tap or an overflowing toilet it will show as leakage.

Leakage is reported in three key ways:

  1. Cubic metres per kilometre of water main per day (m³ per km of main/day)
  2. Mega-litres per day lost (Ml/day lost)
  3. Litres/Property/Day (l/prop/day)

One mega-litre is equal to around 12,500 baths, or 40% of an Olympic size swimming pool.

The method by which companies in England and Wales are required to report is leakage in mega-litres/day. Their targets are all set around this figure. This unit of reporting is not easily comparable and is not a measure that we focus on. We report litres/property/day for our Key Performance Indicators.

Our latest leakage figures for financial years (1 April – 31 March) are:

Financial year

m³ per km of main/day

Ml/day lost



















These figures compare favourably to the 2022/2023 performance of Manx Utilities and some water companies in England:

Water Supplier

m³ per km of main/day

Ml/day lost


Manx Utilities




Thames Water




Yorkshire Water




United Utilities




Anglian Water




Northumbrian Water




Data for English water companies from and OFWAT. 

The 2023/2024 leakage data is not available yet for all UK companies.