Non-revenue water reduction through pressure management in Kozani's water distribution network: from theory to practice

During the last few years, many water utilities are facing difficulties with the high non-revenue water (NRW) levels. Among the NRW management strategies, water pressure management (PM) is the most popular towards the goals of effective and efficient water use. In an effort to improve the level of services provided to consumers, minimize its operating expenses and reduce water leakage and pipes' bursts, water utilities rely on water PM although it is one of the most expensive methods. This study analyses a methodology of calculating economic benefits and revenue losses caused due to the reduction of a system's operating pressure. The reduction of System Input Volume causes direct benefits (e.g. reduced energy costs), while the reduced burst frequency causes direct (e.g. maintenance cost reduction) and indirect potential benefits (e.g. reduction in personnel, insurance and vehicle operation costs). The revenue losses are caused mainly due to the reduction of pressure-dependent water consumption. In the case of Kozani city in Greece, the economic impact of dividing its water network in District Metered Areas and applying 5 PM interventions based on installing Pressure Reducing Valves is calculated, using the system's hydraulic model.