Contact us:
Choose language:
Follow us

IWA Water Balance

The major challenge facing water utilities and municipalities is how to deal with high levels of Non-Revenue Water (NRW). To most water utilities, the level of NRW is a key performance indicator of efficiency. However, most utilities tend to underestimate NRW because of institutional and political pressures, as well as a lack of knowledge to properly determine the NRW level.

Quite simply, Non-Revenue Water (NRW) is the difference between the volume of water you produce and the volume of water you sell (billed).

High levels of NRW reflect huge volumes of water being lost through leaks (real/physical losses), water not being invoiced or not being accurately measured (apparent/ commercial losses) or both.

Only by quantifying NRW and its components, calculating appropriate performance indicators, and turning volumes of lost water into monetary values, can the NRW situation be properly understood and the required actions taken.

The first step in reducing NRW is to develop and establishing a water balance, which process helps utility managers to understand the magnitude, sources, and cost of NRW. The water balance typically traces the flow of water from the site of water withdrawal or treatment, through the water distribution system, and into customer properties.The water balance  usually exists in the form of a worksheet or spreadsheet that details the variety of consumption and losses that exist in a community water system. 

The water balance tells us how much of each type of loss occurs and how much it is costing the water utility. The key concept around this method is that all water is quantified – via measurement or estimate – as either a form of beneficial consumption or as wasteful loss. 

The International Water Association (IWA) has developed a standard international water balance structure and terminology that has been adopted by national associations in many countries across the world (Figure 1) 

Figure 1. IWA Water Balance (All data in volume for the period of reference, typically one year)

Aquasave is using water balance software to collate and present the water balance data and results in a standardised format recommended by IWA. The software is designed to aid the user in making sense of the overwhelming quantity of data that is generated by a comprehensive water balance. The software incorporates the calculation of an extensive range of key performance indicators including ILI (infrastructure leakage index).

Let Aquasave lead you in your IWA Water Balance and ensure that your water loss reduction goals are achievable, cost effective and successful. Contact us at: