Non-revenue water & leakage

Non-revenue water (NRW) is a serious concern for all water utilities worldwide. Water is an increasingly scarce commodity with an economic cost and losses have economic, environmental, social and health consequences. Where drinking water is obtained from desalination the direct economic costs are even greater. And excessive NRW can have political consequences especially where water is scarce.

Minimising NRW is a major priority and a never-ending activity – leakage is never entirely beaten but it can be reduced to and maintained at optimum and acceptably low levels. Our expertise in NRW focuses on physical losses; leakage on transmission & distribution mains and leakage on service connections up to the point of customer metering. We advise water utilities in many countries on addressing and reducing NRW through system leakage.

 This is achieved through some or all of:

  • Leak and defect detection using internal or external detectors and correlators or direct vibrational technologies.
  • District metering area (DMA) isolation and investigation.
  • Metering & flow monitoring
  • Software for real-time analysis of flow data.
  • Hydraulic modelling.

We aim to answer 3 key questions in system losses:

  • Are there leaks?
  • Where are they?
  • How big are they?

Analysis of the results along with engineering expertise enables Infrastructure Leakage Index (ILI) calculation & targeting and estimation of water balance. Initial operational measures such as pressure management and active leakage control can be implemented and can have significant impact on NRW while  longer-term solutions such as rehabilitation or replacement are planned.

Non-surfacing leak at water main joint
Non-surfacing leak at water main joint
Options for reduction in annual real losses
Options for reduction in annual real losses
Surfacing water main leak
Surfacing water main leak


  • Reduction in non-revenue water
  • Repair & rehabilitation interventions to minimise network losses
  • Operational network optimisation