Comparative analysis of rainwater quality from rooftop harvesting systems in a university staff residential buildings

Abstract

Access to clean water is a pressing global issue, with millions of people relying on rainwater harvesting as a supplementary water source. However, the quality of harvested rainwater is often compromised by contaminants from roofing materials, posing serious health risks to consumers. This study assesses the quality of rainwater captured from galvanized steel, aluminum, concrete, asbestos, and thatch roofs in Taraba State University's Jalingo staff quarters, with a focus on essential physicochemical and bacteriological characteristics. Key water quality metrics were investigated, demonstrating considerable impacts from roofing materials. Lead levels in galvanized steel and asbestos roofs (0.015 mg/L and 0.020 mg/L) surpassed WHO guidelines, while fecal coliform counts in thatch and asbestos roofs (9-10 CFU/100 mL) made the water unsafe to drink. Aluminum and concrete roofs produced superior results, with lead levels below 0.01 mg/L and turbidity below 3.0 NTU, however microbiological contamination remained. The findings emphasize the need of using proper roofing materials and water treatment technologies to improve the safety of captured rainwater for home usage. The study concluded that, while rainwater collection is a sustainable water supply, it requires adequate roofing materials and water treatment procedures to ensure water safety. These findings are useful for improving water resource management in areas that rely on rainwater gathering.