The concept of Background Leakage originated in the UK in the early 1990s and is an essential element of the Burst and Background Estimates (BABE) component analysis methodology. It is embedded in the UARL formula used to calculate the Infrastructure Leakage Index (ILI), in economic level of leakage (ELL) calculations, and in assessments of the minimum achievable levels of leakage in DMAs. However, for more than a decade there have been concerns that Background Leakage may not behave as originally defined, and recent research — including the UK Ofwat-funded “Managing Background Leakage” project — has shown a clear need to update our understanding.

The initiative will summarise current knowledge, collect and analyse DMA leakage data to review minimum achieved and minimum achievable leakage levels, gather international case studies on intensive leakage control, and document techniques for tackling background leakage. Its primary objective is to update the understanding of Background Leakage with data and experience from around the world. Following the project kick-off in 2026, a draft report is planned for September 2027, with final publication targeted for the Water Loss 2028 conference.

The standard IWA Water Balance, first published in 2000 by the first IWA Water Loss Task Force and the Performance Indicators Task Force, is now used and recommended by utilities, consultants, regulators and international funding agencies in an ever-increasing number of countries. Over the past two decades, however, water balance software and national practice have introduced enhancements not reflected in the original standard — such as separating System Input Volume into Water from Own Sources and Water Imported, and treating Water Exported as a distinct component, which is essential for systems, zones and DMAs with both inlets and outlets.

This initiative will review a selection of existing international water balance formats (IWA and AWWA based), evaluate their advantages and disadvantages, and propose updates to the standard IWA Water Balance that address these enhancements. It will also consider how any changes would affect the calculation of standard NRW and Real Losses performance indicators. A draft White Paper and webinar are planned for June 2027, followed by an implementation timetable and action plan by December 2027 and final publication at Water Loss 2028.

Launched in June 2023 and run in collaboration with the IWA Benchmarking, Performance Assessment and Regulation Specialist Group, the Global Water Loss KPI Initiative addresses the growing international demand for reliable, comparable water loss performance data. The initiative has three main objectives: to assess current practices in the use of water loss KPIs across different countries; to collect a global set of water loss KPIs, assembled with careful regard to data quality; and to prepare Guidance Notes on best practices and challenges in the use of water loss KPIs.

Work to date has included a country-by-country review of organisations developing or using water loss KPIs, an international questionnaire, and global data collection using structured country and utility datasets. The Guidance Notes will cover KPI definitions, the applicability of individual indicators in different contexts, uncertainty and sensitivity analysis, and approaches to target setting. Data analysis includes an estimate of the global NRW volume, and the results of the initiative are being presented at the Water Loss 2026 conference in Rio de Janeiro, with completion of the remaining outputs to follow.

The service pipe connects the customer property to the distribution network. In many regions this pipe is owned by the customer, yet it is prone to leakage and often forms part of the utility’s reportable leakage figures. Nuanced ownership models make these leaks difficult for utilities to find and repair, leaving a significant share of water loss relatively uncontrolled, particularly at unmetered properties. Management practice differs widely both nationally and internationally, and there is limited understanding of best practice.

The initiative aims to quantify the level of service pipe leakage internationally in the context of different management strategies, and to establish a best practice service pipe leakage management model. Activities include building an understanding of service pipe materials and asset condition, analysing regional differences in leakage levels and measurement approaches, comparing ownership and management models, examining the economics of service pipe repair, and reviewing state-of-the-art technologies for service pipe leak detection and repair. An international benchmarking database has been developed, and work is continuing on enhancing the database and completing the second phase of the analysis. Deliverables include a position paper and best practice guidance.

The New Technologies Initiative brings together global experts to explore, classify and share information about innovative technological solutions for reducing NRW in urban water distribution systems. It responds to the growing pressure on utilities to deliver efficient, sustainable services in the face of ageing infrastructure, limited resources and increasing demand. To keep the work focused on truly new and transformative solutions, the initiative has developed clear criteria for what qualifies as a “new” technology and organises solutions into six strategic categories: advanced sensing and monitoring; data-driven decision support; innovative leak detection and repair; smart infrastructure and pressure management; pipeline rehabilitation and asset management; and customer engagement and water use efficiency.

Launched in April 2024, the initiative is compiling a categorised, searchable Technology Database with technical documentation and use cases — the first version of which was finalised in September 2025 — and has prepared the first New Technologies Guide, published in March 2026. Alongside the database and guide, the initiative delivers a position paper, conference presentations and a platform for international knowledge exchange, serving as a reference hub for technology selection by utilities, regulators, funders and industry stakeholders.

View the publications.