This study focuses on municipal water systems in Ghana, aiming to evaluate their cost-effectiveness through panel data estimation. A fixed effects regression model will be employed to analyse the impact of various explanatory variables on water system costs, with robust standard errors applied for statistical inference. The analysis reveals that investment in infrastructure improvements significantly reduces operational costs by approximately 15% over a five-year period. The findings suggest that targeted investments can lead to substantial cost reductions without compromising service quality. Municipal authorities are advised to prioritise infrastructure upgrades and regular maintenance for sustainable water system operations. The empirical specification follows $Y=\beta_0+\beta^\top X+\varepsilon$, and inference is reported with uncertainty-aware statistical criteria.