Implementing decentralized rural water treatment: passive chlorination and UV disinfection [MSc Thesis, University of Oxford]

Abstract: Critical developments are needed within rural water service delivery models to align with Sustainable Development Goal 6.1. This study focuses on the implementation of passive chlorination and ultraviolet (UV) disinfection for water treatment. Both technologies reduce health risk from microbiological contaminants in drinking water; a key difference is the effectiveness of UV against pathogens like cryptosporidium versus the ability for chlorine residuals to provide continued protection. Based on a synthesis of existing research, an implementation science framework (RE-AIM) was employed to uncover the necessary improvements needed for sustainable long-term implementation. A qualitative content analysis of 26 stakeholders involved in passive chlorinator and UV projects in rural areas in South America, Africa and Asia, revealed key implementation trade-offs. The results identify challenges in securing local supply chains, ensuring financial sustainability, and establishing service delivery models. Recommendations focus on local collaboration, creative financing strategies, and contextualization of technologies.

Causal loop diagram of implementation environment of passive chlorination and UV technologies

CLDs are a form of systems mapping that involve boxes, connections and loops to indicate reinforcing (positive) and balancing (negative) feedbacks in a system (Barbrook-Johnson and Penn 2022: 48–49). This figure presents a CLD of the implementation environment of PC and UV-C LED technologies, where the connections and boxes are color coded according to the five components of RE-AIM: Reach, Effectiveness, Adoption, Implementation and Maintenance/Sustainability. Further, positive and negative feedback loops are indicated by ‘+’ and ‘-’ symbols, respectively.