INVESTIGATING NON-REVENUE WATER IN URBAN WATER SUPPLY: A CASE OF BLANTYRE WATER BOARD

Non-Revenue Water (NRW) poses a significant threat to the operational efficiency and financial sustainability of water utilities, particularly in developing countries. This study investigated NRW in urban water supply, a case study of Blantyre Water Board. Specifically, the study aimed to determine the trend of NRW, assess its financial impact on BWB, identify the causes of NRW, and evaluate the strengths and weaknesses of NRW reduction strategies implemented by the utility. Mixed-methods approach was adopted to enhance the validity and reliability of the findings through triangulation of quantitative and qualitative data. Quantitative data covering the period 2015–2024 were analyzed using descriptive statistics, trend analysis, correlation, and regression analysis, while qualitative data were collected through key informant interviews to provide contextual explanations of the observed trends and operational challenges. Inferential statistical analysis was conducted at a 95% confidence interval, and statistical significance was determined at p < 0.05. The integration of qualitative findings helped explain relationships and patterns that could not be sufficiently interpreted through quantitative analysis alone. The study employed purposive sampling in selecting key informants. Respondents were deliberately chosen based on their professional knowledge, technical expertise, involvement in procurement management, water supply management and NRW water control within BWB. The results indicate that NRW exhibited a fluctuating but increasing trend, rising from 40.8% in 2015 to 61.9% in 2024, with a mean of 49.82%, far exceeding recommended benchmarks. A strong positive correlation of 0.681 was found between water production and NRW, indicating that increases in water production were associated with corresponding increases in water losses. In contrast, billed consumption showed a negligible negative correlation of 0.047 with NRW, suggesting minimal influence on NRW variation. Financial analysis further revealed that the BWB transitioned from operational surpluses to sustained financial deficits after 2020 due to rising production costs and escalating water losses. The study estimated v INVESTIGATING NON-REVENUE WATER IN URBAN WATER SUPPLY: A CASE OF BLANTYRE WATER BOARD that the utility incurred cumulative financial losses of approximately MWK 31.3 billion between 2021 and 2024 as a result of NRW-related inefficiencies. Qualitative findings identified key causes of NRW, including aging infrastructure, leakages, inadequate metering, illegal connections, and institutional inefficiencies. While existing strategies such as leakage control and metering improvements have yielded some benefits, their effectiveness is constrained by limited resources, weak monitoring, and lack of sustained implementation. The study concludes that persistently high NRW, driven by interconnected technical, administrative, and socio-economic factors, has significantly undermined the financial sustainability of BWB. vi