Water treatment facilities in Tanzania face challenges related to system reliability due to varying economic conditions and operational environments. A multilevel regression analysis will be employed to model the influence of economic conditions (at the district level) and operational environments (at the facility level) on water treatment system reliability in Tanzania. The study will use a dataset comprising over 50 facilities across 10 districts, with data collected through surveys and official records. A significant proportion (34%) of surveyed facilities reported maintenance issues related to financial constraints at district levels, highlighting the need for integrated economic support strategies. The multilevel regression analysis confirmed that both economic conditions and operational environments significantly impact water treatment system reliability in Tanzania. The study provides a novel methodological framework for evaluating such systems. Policy makers should prioritise financial assistance to districts with lower maintenance levels, while also improving monitoring and maintenance protocols at facility level to enhance overall system performance. water treatment facilities, multilevel regression analysis, reliability, economic conditions, operational environments The maintenance outcome was modelled as $Y_{it}=\beta_0+\beta_1X_{it}+u_i+\varepsilon_{it}$, with robustness checked using heteroskedasticity-consistent errors.