Big question

How will we achieve zero leakage in a sustainable way by 2050?

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Leaks from underground pipes are a reputational issue for all water companies.  Since 1997, leakage has been reduced by 40 per cent.  Even still, 20 per cent of all the drinking water produced is still lost – from companies’ pipes, homes and businesses.

Customers, regulators and Government expect water companies to reduce leakage much further.  In England and Wales, water companies have already started to reflect those expectations and pledged to reduce leakage by a further 461 million litres per day, or 16%, between 2020 and 2025.

Leakage Innovation Heatmap

This work has been carried out by Jeremy Heath of SES Water, in his capacity as the programme lead for Leakage Big Question. The purpose of this exercise was threefold

  1. To generate a UK industry-wide innovation heatmap for leakage, which captures the current research programmes.
  2. To assist in the development of the UKWIR Leakage Big Question, by identifying those areas where there is little research currently taking place.
  3. To foster collaboration between Companies by highlighting those areas where multiple companies are working on similar projects.

It is important to understand that the projects lists are not exhaustive and inter-company comparison on the levels of leakage innovation are not valid. Some companies have been unable to provide their full project list due to contractual or non-disclosure agreements. Some companies have listed projects separately, whilst others have grouped them together (for example smart networks). This exercise has only sought to capture a small segment of all of the innovative work being carried out by water companies, in order to develop research plans and promote collaboration on leakage innovation.

If water companies wish to initiate contact to discuss the potential for shared projects, they can contact Jeremy direct and he will be able to direct them to the relevant person in the other water company for that particular project. Supply companies, who may wish to discuss the benefit that they can bring to some of these projects, should use the existing channels to contact the relevant Company.

Leakage Innovation Heatmap 


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Achieving Zero Leakage by 2050: Phase 2: Understanding the balance between customer use, supply pipe leakage and plumbing losses in water delivered to household properties

Project Status - Project submitted as Complete

This project will use recently developed flow estimation techniques to investigate these factors across a representative sample of household properties within several water companies.  

The data obtained will be used to provide greatly improved estimates of: 

  • Plumbing losses, which are part of consumption
  • Water running into storage at night, also part of consumption
  • Background leakage on underground supply pipes, which is part of the total leakage KPI


BQ Achieving zero leakage by 2050: Project 1 - Use of smart meters and smart networks for leakage management

Project Status - Project submitted as Complete

Category - Leakage

Modern technology has made it possible to collect much greater quantities of data, and at higher resolution. Leakage analysis methods and leak detection technology have both made many advances in recent years, but data collection and manipulation processes have hardly changed. The basic principle of measuring minimum night flow into a DMA, and then subtracting estimates of household and non-household night use to give leakage, remains unchanged in the past 30 years.

However the recent growth in smart networks, and particularly the use of smart meters for revenue purposes, could offer many new opportunities for better leakage management. It is essential that these opportunities and benefits are identified now, so that water companies can take them into account when making their choices of which smart technologies to invest in.


The impact of reductions in leakage levels on reported and detected burst frequencies

Project Status - Project Completed

Category - Water Mains, Sewers and Services

The Water Industry has very little knowledge of the impact of reducing leakage levels on the numbers of repairs that need to be carried out each year, nor on the relative proportions of visible and invisible leaks.

Introduction of performance commitments and changes in SIM, with associated rewards and penalties, has increased focus on the customer service aspects of burst and leak repairs, whether it is unwanted contacts, interruptions to supply or associated discolouration contacts. Customer Service impact mitigation costs will add to the operational costs for repair and consequential damage.

Historic leakage strategy has focused on Sustainable Economic Level of Leakage (SELL). Leakage strategy now must consider the customer acceptability aspects of leakage. Most customer views are based on the impacts of visible or reported leaks and the impact of repairs on customer service.

Single company data is insufficient to discern any impact due to leakage level as it is masked by weather and relatively static targets. Pooled company data, combined with planned AMP6 reductions should provide a data set to understand any increases in repair frequency, changes in proportions of visible leaks and the time period for change.

Projects coming soon.


Achieving zero leakage by 2050: Leakage detection by acoustic methods

Project Status - Project submitted as Complete

No Further Information Currently Available.


Active Leakage Control efficiency in the SELL calculation Renamed: Active Leakage Control Efficiency

Project Status - Project Commenced

Category - Water Mains, Sewers and Services

Both Ofwat and the Environment Agency (EA) have said recently that they have some concerns with the current Sustainable Economic Level of Leakage (SELL) process for the setting of leakage targets.  The recent EA guidance on leakage for Water Resource Management Planning (WRMP19) says :

There is increased realisation that SELL may not be the most effective way to plan leakage levels.  WRMP19 will be the final time that a leakage figure is derived from SELL.  We expect water companies to evolve and move away from SELL for WRMP24 and to innovate to reduce leakage beyond the current levels”.

 The Ofwat consultation document on outcomes for PR19 (February 2017) expresses a different view :

“Companies should report their SELL in business plans, explain their assumptions on future improvements in leakage reduction efficiency in the SELL, and explain how its Performance Commitment for leakage is appropriate in relation to SELL”. 

 There is a strong feeling amongst companies that leakage targets should continue to be based on a sound economic analysis.  However, the cost of leakage management relationship for SELL modelling is derived from analysis of the company’s own historical leakage management performance data.  It is therefore a valid criticism of this process that if a company has been historically inefficient, then this inefficiency becomes built into the SELL.


BQ Achieving Zero Leakage by 2050: Phase 2 - Hydrant dynamics for acoustic leakage detection PhD

Project Status - Project Commenced

Category - Leakage

No Further Information Available.


Achieving zero leakage by 2050: Project 2 - Incidence and causes of repeat bursts at old repairs

Project Status - Project Commenced

Category - Leakage

Distribution Maintenance staff at water companies know well that many leaks and bursts, once excavated, prove to be at the location of a previous repair, and occur as a result of a failure of the old repair. However it is not known how much data is collected on this, and there is no quantitative evidence of the magnitude or significance of this problem at national level. Nor has there been any study of the reasons for the failures, i.e. whether they are due to deterioration of the clamp or other repair materials over time, or whether they are caused by faulty workmanship at the time of the initial repair.

Many companies do record the types of failure within their records of mains and service bursts. However these descriptions are often very brief (e.g. “pin-hole”), and the fact that the failure was at a previous repair may not be recorded. This project will initially assess the availability of suitable data, in collaboration with participating water companies. The UKWIR National Mains Failure Database may also be a valuable source of data.


Impact of Customer-side Leakage Approaches

Project Status - Project Commenced

Category - Water Mains, Sewers and Services

It is estimated that about 25% of the leakage within a water distribution network is located on a customer's property and occurs within the pipe that is not the responsibility of the Water Companies. However, this is still included in the leakage figures that water companies report to regulators.

The customers can be divided into household and non- household. For household customers, water companies offer a range of solutions from providing free advice to free repairs. There is limited understanding of how these different policies ultimately impact on reported leakage levels and overall cost to the business. For non household customers, water companies don't provide free repair services as a part of their standard customer leakage policy. However, with the opening of retail market, communication with non-household customers has become difficult, slowing down the leak repair and increasing the level of leakage.

Water Companies are also increasingly installing smart metering which identify leaks with very low flowrates. This has challenged the industry to find such small leaks, which are not cost effective to repair, and can be difficult to locate.

Projects coming soon.

Projects coming soon.