Water treatment facilities play a critical role in ensuring safe drinking water supply in Uganda, yet their effectiveness is not fully understood. A mixed-method approach combining quantitative analysis of facility performance data with qualitative interviews to assess system maintenance practices and user satisfaction. Analysis revealed a significant reduction (p < 0.05) in microbial contamination levels post-treatment, with confidence intervals indicating robustness of the findings. The replication study supports the efficacy of existing water treatment facilities in mitigating health risks from contaminated water sources. Further research should explore long-term sustainability and socio-economic impacts to inform policy decisions. The maintenance outcome was modelled as $Y_{it}=\beta_0+\beta_1X_{it}+u_i+\varepsilon_{it}$, with robustness checked using heteroskedasticity-consistent errors.