Enhancing Water Management in the City of Umhlathuze Local Municipality in Kwazulu Natal by Analysing its Historic Metering Data

Abstract

This study examines historical metering data from March 2016 to September 2020 for billed residential areas within the City of uMhlathuze Local Municipality to identify trends in residential water consumption and provide insights into sustainable water management. Understanding consumption patterns among billed customers is critical in assessing the extent of excessive water consumption and its implications for water resource sustainability. By analysing these trends, this research enables comparative assessments with other municipalities, offering valuable insights into the effectiveness of existing water management strategies and proffering recommendations to improve water usage. The study employs Change Point Analysis and Water Demand Models, incorporating linear, log-log, and semi-log regression techniques. Change Point Analysis is utilised to detect significant shifts in water demand driven by policy interventions such as the introduction of drought tariffs, seasonal variations, and socio-economic factors. The analysis reveals that residential water consumption in the municipality remained relatively stable, averaging 23,190 kl/d between March 2016 and September 2020. Further, the Water Demand Model analysis identifies the log-log model as the most representative of the municipality’s water usage trends, with an R-squared value of 70%, indicating a relatively strong fit. The number of service connections emerges as a key determinant of water demand, with a statistically significant P-value of 0.01, emphasising its impact on consumption patterns. Non-revenue water (NRW) accounts for 27% (or 88 L/c/d) of the total system input volume (327 L/c/d). The study found that excessive residential water consumption is not currently a significant concern, with an average residential per capita consumption of approximately 143 litres per person per day, which is categorised as excellent water use management. The resulting total Revenue Water figure of 239 L/c/d reflects the total system's efficiency in billing all sectors (residential, commercial and industrial). However, network inefficiencies due to aging infrastructure remain. Addressing these inefficiencies requires infrastructure upgrades, improved metering accuracy, and enhanced leak detection measures. Additionally, incorporating unauthorised users into the billing system can contribute to reducing NRW and improving revenue generation. The study recommends a series of targeted interventions, including infrastructure maintenance, smart metering deployment, public awareness campaigns, and optimisation of industrial water use. Implementing these measures will strengthen water conservation efforts, ensure long-term sustainability, and promote equitable water distribution within the municipality.