A LIFE CYCLE ASSESSMENT OF AN URBAN WATER SUPPLY SYSTEM IN TANZANIA

Abstract

The increase in water demand resulting from population growth is a growing concern in Tanzanian cities, municipalities, and towns. Water utilities are working towards achieving the sixth Sustainable Development Goal (SDG), which aims to provide the general public with safe and sufficient drinking water. Water supply systems in cities, municipals, and towns across Tanzania are being developed, retrofitted, rehabilitated, and extended, causing environmental impacts. Reducing the environmental effects associated with an urban water supply system (UWSS) is essential to safeguarding the health of our community's residents and the ecosystem, although it has not been well explored. Using the Life Cycle Assessment (LCA), this research assesses the environmental impacts of the Iringa UWSS on the supply of 14.5 MLD to the general public. The study strictly followed the structured LCA guidelines set by the International Standards Organization (ISO). The inventory information pertaining to the operational stage falling within the scope of this study was gathered. Four scenarios, with an electricity grid mix, with hydropower electric energy, with solar power, and with natural gas, were analyzed, and results were compared. LCA was carried out using the GaBi Education software and the ReCiPe Midpoint impact method. The findings indicate that the electricity grid mix scenario, which relies on conventional energy sources, has a more significant environmental impact than scenarios utilizing hydropower, solar, and natural gas as sources of electricity. Similarly, in the electricity grid mix scenario, the results showed that the high energy consumption in the transport and distribution stage is a significant factor in the environmental effects, followed by the water abstraction and, finally, the water treatment stages. Based on the results, the hydroelectric power scenario is the most environmentally friendly option for improving the UWSS, as it has been found to reduce the negative environmental impacts by approximately 90% significantly. Therefore, it is recommended that energy be derived from renewable sources, such as solar and hydroelectric power, and energy-saving techniques, such as automation in water pumping.