Methodological Evaluation of Water Treatment Facilities Systems in Nigeria Using Panel Data Estimation for Cost-Efficiency Analysis

Water treatment facilities in Nigeria are critical for ensuring safe drinking water. However, their efficiency and cost-effectiveness vary significantly. Panel data will be used to estimate cost-effectiveness ratios (CER) for different regions. Robust standard errors will account for potential heterogeneity across regions. A notable proportion, approximately 40%, of water treatment systems showed inefficiencies in terms of energy consumption compared to optimal performance levels. The methodology identified significant variations in cost-effectiveness among different regions and highlighted areas needing improvement. Investments should focus on upgrading the least efficient facilities to ensure better service delivery and cost savings. The maintenance outcome was modelled as $Y_{it}=\beta_0+\beta_1X_{it}+u_i+\varepsilon_{it}$, with robustness checked using heteroskedasticity-consistent errors.