Decentralized UV disinfection systems in rural areas or low-resource contexts: a case study compilation

Abstract

Water disinfection using ultraviolet (UV) light is an emerging tool for improving access to safely managed drinking water in rural areas and low-resource regions. However, there is little information comparing existing UV systems in those contexts, towards improving the effectiveness of future UV systems. This work presents 19 case studies of small, decentralized UV water disinfection systems being used during the last 30 years to improve water access. The case studies cover a wide range of project types, including schools, hospitals, communities, households and healthcare facilities, spanning four continents. A variety of energy sources, water sources and social environments are also reviewed. In general, the use of UV immediately improved the microbiological quality of the water; however, long-term tracking of system performance is largely missing. UV system effectiveness was limited by several factors, including the potential for recontamination after UV disinfection, insufficient maintenance, and the absence of regulatory frameworks that allow the more widespread adoption of UV disinfection compared to more conventional disinfectants. This paper is intended to be supporting evidence for the utility of UV technologies for improving safe water access in low-resource settings, and to support practitioners in improving UV system design and implementation.