INCREASING THE IMPACT AND SUSTAINABILITY OF SAFE DRINKING WATER SUPPLY IN RURAL BANGLADESH: RANDOMIZED EXPERIMENTS WITH INTERVENTIONS IN THE PROJECT LIFE CYCLE

Access to safe drinking water is a global challenge, as reflected in Sustainable Development Goal 6. In Bangladesh, bridging the gap between those with safely managed drinking water and those with improved sources is a pressing issue. This study estimates causal relationships between interventions in the project life cycle and their impact on sustainable access to safe drinking water in rural areas. A series of Randomized Control Trials (RCTs) were conducted across different regions of Bangladesh over 15 years of tubewell construction programs to provide arsenic free safe drinking water. The RCTs evaluated changes to decision-making processes, contribution requirements, and maintenance practices. Community participation in decision-making processes can enhance the impact and sustainability of safe drinking water programs. Requiring communities to contribute financially or through labour does not necessarily increase program impact, and it can lead to reduced take-up, and decreased cost-effectiveness though it may increase sustainability. Community water sources are less effective than expected due to contamination introduced during collective use and issues related to transport and storage: they help to mitigate arsenic exposure but do not effectively address faecal contamination. Disinfecting tubewells with a weak chlorine solution reduced faecal contamination. Caretakers standard cleaning practices do not generally, adhere to best practices and may worsen water quality. However, training caretakers in best practices proved highly effective in reducing Escherichia coli contamination, significantly improving water quality. Despite some imperfections in caretakers' recall and compliance, these results highlight the crucial role of proper cleaning and maintenance practices in reducing exposure faecal contamination in rural Bangladesh, ensuring access to safe drinking water. The study highlights the power of RCTs in addressing complex causal questions related to safe drinking water access. While valuable insights have been gained, the study emphasizes that numerous unanswered questions remain, underscoring the ongoing need for research in this critical field. In summary, this study provides important evidence about how to improve project design and thereby increase access to safe drinking water in rural Bangladesh.