Non-revenue Water Management for Intermittent Supplies (IWS)

In many world regions Intermittent Water Supply (IWS) systems are prevalent. IWS systems can be defined as piped water supply service that is available to consumers less than 24 hours per day. In an IWS situation, the consumers usually secure their water supply through the use of ground or roof tanks, where water is stored during the length of time that the supply is provided.

Although there is a generic approach for quantification and management of NRW based on IWA best practices, their application to intermittent water supply systems poses great challenges to practitioners.

The numerous problems associated with management and operation of distribution networks under IWS as well as the critical challenges entailed in moving to 24/7 forms the core objectives of the Task Group. The work that will be undertaken by the Task group will help to better understand what the root causes of intermittent supply are and how to apply, in a simple and practical manner, the existing NRW body of knowledge to utilities with intermittent water supply and to document in a structured manner cases that were successful to move to continuous supply.

A manual of best practice for managing NRW for Intermittent Supplies including practical diagnostic and remediation tools and case studies. These to be followed later by an impact assessment survey to establish on-the-ground outcomes and ascertain the degree of true change that was brought about. During the period of preparing this report, mainstreaming of deliverables and knowledge products will be presented through the organisation of workshops at key international and regional IWA events to report on progress and content of best practice manual, and through raising awareness about the work on intermittent supply amongst key players such as governments, utilities, regulators, IFIs, donors, etc. The final result will be presented at the  IWA World Water Congress, 2016.