We present a new micro-based approach to evaluate the effect of water- and health related development projects. We collect information from 1.8 million individuals from DHS clusters (Demographic and Health Surveys) in 38 developing economies between 1986 and 2017. By geocodes, we combine cluster information with over 14,000 sub-national projects from the World Bank. We then investigate the impact of the projects employing fixed-effects estimation techniques. Our findings indicate that the time to gather water and child mortality tend to decrease when projects are realized. The quality of drinking water and sanitation facilities are positively affected too by projects. Our data allows us to account for cluster heterogeneity, which is a significant extension to the cross-country literature. Robustness checks, covering data and methodological refinements, supports our main findings.