ABSTRACT
This study was carried out to investigate the physicochemical quality of the roof harvested rainwater based on roofing material with a primary focus on its potential as a sustainable water source for household purposes. Rainwater from roof types; asbestos, aluminium, zinc was harvested during peak rainy season, analysed for water quality parameters and compared with non-roof harvested rainwater. The harvested rainwater samples were analysed for water quality parameters (acidity, alkalinity, bicarbonate, sulphate, calcium, magnesium, potassium, sodium, iron, lead, chromium, pH, total dissolved solids (TDS), and electrical conductivity (EC) using standard procedures. The results obtained from the study showed that asbestos and zinc roof harvest rainwater had a high concentration of lead (0.05 mg/l) and high acidity 4.5 compared to other roof types as well as non-roof harvested rainwater. Zinc roof-harvested rainwater had a high concentration of sulphate (0.15 mg/l), lead (0.005 mg/l), iron (0.059 mg/l), and chromium (0.02 mg/l) compared to other roof types and non-roof harvested rainwater. The result of the analysis also showed that asbestos roof-harvested rainwater had alkalinity (19.83) and high concentration of bicarbonate (16.25 mg/l), lead (0.05 mg/l) as well as essential elements; calcium (5.932 mg/l), magnesium (1.264 mg/l), potassium (0.709 mg/l) and sodium (0.973 mg/l) compared to other roof types and non-roof harvested rainwater. The study revealed that though the roof harvested rainwater quality parameter were within the permissible limit of the World Health Organisation the concentrations of the parameters were more compared to that of non-roof harvested rainwater in the study area.
