Quality Assessment of Harvested Rain Water Collected From Corrugated Iron Rooftops in Mubi Metrapolis, Adamawa State, Nigeria

Abstract

This study comprehensively evaluates the quality of harvested rainwater collected from corrugated iron rooftops in Arahan Kunu and Chandal within Mubi Metropolis, Adamawa State, Nigeria. Rapid urbanization and chronic municipal water supply deficits have forced these communities to rely heavily on harvested rooftop rainwater for daily domestic needs. Nine seasonal rainwater samples and corresponding ground-level controls were collected during May, July, and September to systematically assess the direct impact of catchment surfaces on water safety. Essential physicochemical parameters, including pH, temperature, dissolved oxygen, and biochemical oxygen demand, were measured alongside total coliform bacterial counts using standard laboratory protocols. Trace heavy metal concentrations, specifically zinc, lead, cadmium, nickel, manganese, and chromium, were carefully quantified using Atomic Absorption Spectrophotometry following a comprehensive microwave-assisted sample digestion method. The investigation focuses on characterizing localized chemical contamination pathways driven by atmospheric deposition, dry-season dust, animal droppings, and rooftop material leaching via accelerated corrosion. By modeling toxicological suitability and microbial risk profiles, this paper successfully establishes a critical baseline for domestic water safety. The ultimate goal is providing empirical data to guide localized first-flush diversion practices and essential public health interventions within water-scarce sub-Saharan semi-urban environment landscapes.