Partitioning non-revenue water for Juru Rural Service Centre, Goromonzi District, Zimbabwe

Abstract

Most water supply utilities in developing countries are faced with challenges of high Non- Revenue Water (NRW). Juru Service Centre water supply system is owned and operated by the Zimbabwe National Water Authority (ZINWA). The study analysed NRW trends from 2012 to 2020 and partitioned NRW according to the IWA Water Balance. Historical data on water production and consumption maintained by ZINWA was used to assess NRW trends. Flow measurement by loggers was used to determine real losses through Minimum Night Flows (MNF) analysis. To assess the impact of meter errors and billing anomalies, meters were tested on a meter testing bench and field meter readings were carried out. Based on historical data, NRW ranges from 7.1% to 35% and an average of 16% for the period January 2012 to May 2020. However, based on primary data collected during the study period in 2020, the NRW was much higher ranging from 31% to 42% and averaged 36%. Real losses were estimated at 83% of NRW and apparent losses were 17%. Leakage on transmission and distribution mains, and service connections contributed 47% and 53% respectively. It was concluded that the main contributing factor to NRW was the real losses. The study also established that the key driver for apparent losses was unauthorised consumption which contributed to 82.5% of Total Apparent Losses (TAPL). Active leak detection and repair along with investigation of illegal consumption is recommended.