Practical challenges in estimating and managing non-revenue water in Indian cities

Non-Revenue Water (NRW) refers to the volume of water that does not generate revenue to the utility. In this study, we examine three key challenges in NRW estimation in Indian cities. Firstly, the Indian Service Level Benchmarking (SLB) performance indicator for NRW utilizes the Standard International Water Association Water Balance (SIWAWB), which estimates the NRW as the sum of apparent losses, real losses, and unbilled authorized consumption. SIWAWB does not account for the unpaid water bills, which highlight a sizable portion of revenue not recovered by the utilities in India and other developing countries. The Modified International Water Association Water Balance (MIWAWB) framework estimates NRW as the difference between the system input volume (SIV) and the billed and paid-for volume. The assessment of NRW levels for 17 Indian cities of varied sizes and regions showed that median MIWAWB NRW is 59.78%, whereas the SIWAWB NRW is 23.26%, with a median difference of 35.73%. Secondly, we identify that unbilled authorized consumption is high in Indian cities, which also includes the residential use from public taps and standposts. By analyzing the SLB data for five Indian cities, we found that unbilled authorized consumption exceeds the recommended 1% of SIV in four cities, Kanpur (16.28%), Agra (6.69%), Jhansi (3.01%), and Vijayawada (2.12%). Thirdly, flat-rate bills are issued in several Indian cities due to low metering levels and shortage of staff required for meter reading. These challenges highlight the need to revisit the NRW estimation approaches in Indian context. • Lower efficiency in collecting water charges increases the volume of water that does not generate revenue to the municipalities • Unpaid water bills result in higher revenue losses to the municipalities than the apparent and real losses, and unbilled authorized consumption • Flat-rate billing underestimates water usage in Indian cities, necessitating increased metering levels • Indian cities have high unbilled authorized consumption, which contribute significantly to NRW