Amount awarded:£2,363,132
Led by: Dwr Cymru Welsh Water
Partners: Affinity Water, Anglian Water, Severn Trent Water, Portsmouth Water, University of Sheffield, HWM, Invenio Systems
Water companies in England and Wales have Ofwat targets to reduce leakage by 15% in the current planning period to March 2025. Customers and regulators seek a downward trend in leakage which is seen as wasted water; but more importantly wasted power and chemicals for treatment and distribution, adding C02 emissions, impacting the challenge of achieving net-zero carbon, and adding to environmental water abstractions impacting ecology. The problem is c.50% of leakage is due to Background Leakage; defined as the sum of small leaks below a detectable threshold; generally accepted that it can’t be reduced. However, we believe some Background Leakage comes from old long-running leaks, not detected by current methods. This project aims to redefine the detectable limit of leakage to help pinpoint and repair hidden leaks and other factors contributing to background leakage. This benefits customers by creating more sustainable ways of reducing leakage, avoiding increased environmental water abstractions if future leakage targets can’t be met by current means.
Managing Background Leakage is advancing from Phase B to Phase C. Phase B showed a lot of variation in the amount of background leakage on water company assets (mains and communication pipes) and customer side (losses from underground supply pipes and internal plumbing) in different DMAs, from zero in DMA netA2 to 89.1% in DMA netD1, of the Minimum Night Flow level (computed as an average over the time of the field work). Ten DMA’s was a small data set and it is difficult to draw any reliable conclusions. For this reason, during Phase C the field work will be carried out in 15 DMAs, and the rolling average leakage values will be observed to see whether there are any trends to note. Phase C will also try new methods of estimating customer night consumption in order to provide a more reliable estimate of total loss in a DMA. Phase B has indicated that even with the goal of deploying Stop.Watch loggers to every service connection there are practical issues that stop us from achieving 100% coverage. Therefore, some degree of data infilling is needed. In Phase C we will examine different methods using a scaled back level of logging along with other methods to find a practical and economic method for future surveys on completion of the current project.
Field survey work in the 10 Phase B DMAs is now complete. Consumption and customer side leakage data has been analysed. Modeling to localize any probable network leaks is well advanced, and a meeting is planned for 30th October to agree follow up survey work. Field survey work has commenced in the first of the 15 Phase C DMAs. Work has also commenced on the Phase D uncertainty analysis
In this strategically important project for the water industry, we will challenge accepted wisdom regarding the nature of leakage in distribution systems. If we are successful in finding long-running leaks that have avoided detection, we potentially create new sustainable ways of meeting long-term aspirations to halve leakage at lower cost.
