Non-Revenue-Water Assessment in Urban Water Supply

Supplying hygienic and adequate drinking water has become crucial in India. Water losses in water distribution network is an important issue and challenge for water utilities in urban water supply. In India 50 to 60 percentage of treated and supplied water is lost during transmission from water service reservoir to customer service connections. Non-Revenue-Water (NRW) is the portion of water placed by a water utility into the distribution system but could not generate revenue for utility. It consists of sum of Un-Billed Metered, Un-Billed UnMetered consumption, Real Losses and Apparent Losses. Water utilities are losing revenue because of these high levels of NRW and in turn affecting their financial viability. The main objective of water utility is to deliver wholesome water to consumers in sufficient quantity at adequate pressure, continuity and maximum coverage by reducing losses. In this regard a study was conducted in Vijayawada city water utility by using water audit software Water Balance developed by International Water Association (IWA). This study implemented District Metered Area approach by isolating a small area of water distribution network and conducted Minimum Night Flow Analysis to determine the flows of water. This paper provides a review on assessment of present levels of NRW and a strategy to be implemented for reducing NRW. This paper also discusses about the necessity of targeting appropriate performance indicator which is a benchmark for any water utility