It is crucial that a strategic NRW reduction programme is managed and understood from the highest level of the organisation to the lowest. NRW reduction must be an agreed strategy for the entire organisation, based on a holistic NRW master plan.

The first step is to conduct a water audit that includes an assessment and analysis of the performance of the water distribution system, as well as identifying and quantifying areas for improvement. The outcome of the water audit is then used as essential input for the following steps of the NRW master plan that will serve as the basis for expansions, rehabilitations and investment plans as well as their projected returns.

The most important outcome of the water audit is the component analysis of the International Water Association’s Water Balance, setting a baseline for the NRW level. The analysis details the magnitude of each component that make up the total NRW divided into real losses and apparent losses.

Implementing the NRW master plan

The water audit should be implemented as a recurring (annual) event to continuously quantify the effects of the implementation of the NRW master plan on the water balance, and consequently enable the utility to add any required modifications or corrective actions to the master plan. Once completed, the NRW master plan will provide the following information:

Using the right KPIs for NRW

NRW is commonly indicated and reported in high-level reporting as a percentage of system inputs into the system. This approach is acceptable for NRW levels above 20 percent, as the NRW will be high no matter how it is measured. However, NRW as a percentage is primarily a financial indicator that can be affected by many factors and parameters, so it does not give an accurate picture of system performance. For the water utility staff charged with implementing NRW-reducing strategies and activities, the NRW and leakage levels should be reported by specific indicators using cubic meters/kilometres of pipe/day and cubic meters/connection/day.

The International Water Association has further defined the Infrastructure Leakage Index (ILI), which reports actual real losses against expected unavoidable real losses for the system. This is calculated by taking the service pressure, the number of connections and the length of the pipeline into account. By using these additional performance indicators, the utility can target NRW-reducing activities far more effectively in physical areas and water balance components with the shortest and highest payback.

Ensuring the highest return on investments

The key is to identify where the ROI will be highest. Utilising the ELL framework, which is calculated as part of the master plan, will provide the answers. It considers cost-benefit analyses relating to each element of NRW, as provided by the water audit. It also considers the forecasted influence of the reduction in NRW on future investments in treatment plants, raw water abstraction, pumping stations etc., as well as the potential effects on revenue generation and energy savings.