Assessment of Influent–Effluent Water Quality and Operational Practices at Kibuye Referral Hospital Wastewater Treatment Plant, Rwanda

Abstract

Hospital wastewater contains organic and inorganic pollutants as well as potentially hazardous biological and pharmaceutical constituents. This descriptive case study evaluated selected physicochemical indicators and operational practices at the wastewater treatment plant serving Kibuye Referral Hospital, Karongi District, Rwanda. Three occasions of influent and effluent sampling (April–May 2026) were supplemented by interviews with seven hospital and plant personnel. Ratios of reported mean influent and effluent concentrations were used to estimate apparent concentration reductions. Effluent means were 101.9 mg/L for five-day biochemical oxygen demand (BOD₅), 265 mg/L for chemical oxygen demand (COD), 66.0 mg/L for total suspended solids (TSS), 1,104 mg/L for total dissolved solids (TDS), and 40.7 mg/L for total nitrogen (TN); pH was 7.28. BOD₅, COD and TSS exceeded the respective 50, 250 and 50 mg/L screening values reproduced in Rwandan environmental guidance, whereas TDS was below its upper comparison value and pH was within the specified screening range. Apparent concentration reductions were 20.7% for BOD₅, 20.7% for COD, 62.6% for TSS and 41.6% for TDS. The TN estimates were indicative because the inlet series and analytical procedure were incompletely documented. Five of seven informants reported the absence of written inspection procedures, and six reported no wastewater-treatment training. The short sampling period and unmeasured hydraulic conditions preclude conclusions about longer-term treatment performance or permit compliance. Improved analytical traceability, routine monitoring and targeted process diagnostics are priority measures.