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Ways to permanently reduce non-revenue water levels


High leakage levels, inefficient pipe network maintenance, customer complaints and financial losses are some of the top challenges of water utilities. Many of these troubles can be effectively countered – if you know how to nip the problem at the bud by dealing with the issue of non-revenue water (NRW).

NRW is water that has been produced but cannot be billed. The loss can be the result of leakage or overflow (sometimes referred to as physical losses), theft of water or inaccurate metering (also known as apparent losses), or free use (for example, for firefighting). Calculations suggest that more than US$14 billion is lost every year by water utilities around the world due to NRW. The World Bank recommends that NRW should be less than 25% of the total water produced, while in many countries NRW is up to 60%. High levels of NRW are detrimental to the financial viability of water utilities and pose an extra burden on paying customers.

Water utilities incur substantial financial costs in the treatment and pumping of water, and revenues are lost when water – which could have otherwise been sold – are leaked back into the ground. But it’s not just about financial losses. Another study by the World Bank estimates that the yearly volume of physical water losses amounts to 32 billion cubic metres, half of which occurs in developing countries.

Benefits of control and reduction

The benefits of non-revenue water (NRW) reduction and control are many and interlinked. NRW results in opportunity cost for utilities, cities, the environment and broader economy. For water utilities, it is apparent that a reduction in NRW will produce desirable outcomes such as:

  • Improved water services and customer satisfaction
  • Deferred water development costs
  • Decreased energy needs, OPEX and CAPEX
  • Increased operational revenues
  • Lower financing costs
  • Better credit worthiness

Managing non-revenue water

How do water utilities manage their NRW levels? One of the ways of managing non-revenue water is by using hydraulic models. Hydraulic models identify critical parts of the system and optimise pressure control, including an active and economic leakage management. Reproducing the pipe system, the models help to respond to pipe breaks and leaks and optimise pressure control for sustainable leakage reduction.

Successful and long-term management of leakage levels requires an advanced system with reliable data. When considering a non-revenue water solution, some of the questions that should be asked include:

  • Does the solution enable collaboration with all affiliates, such as network operators, water utility managers and operating staff?
  • Does the solution allow the monitoring of water flow in relatively small parts of the distribution network, to provide a snapshot of the real losses?
  • Will there be access to data from various portals such as SCADA, GIS, invoicing and metering for the best representation?
  • Is the process user-friendly and automated? For example, will the system run all analyses and prepare output automatically at chosen time intervals?

Implementing a non-revenue water solution helps optimise and reduce operational costs, as well as improve water supply reliability. Among other benefits, a well thought out plan helps to optimise the use of the existing supply system as well as water resources, reduce legal liability and insurance cost because of fewer main breaks, and identify illegal connections and non-functional or missing meters in the system.

Find out how top water utilities are reducing their NRW levels permanently, while getting back their investment.