Fuzzy Logic Modelling of the Effects of Pollution on Domestic Roof-Harvested Rainwater Quality in Residential and Industrial Environments

This study presents the effects of environmental pollution on the quality of domestic roof-harvested rainwater (DRHRW) using fuzzy comprehensive assessment (FCA). Seven metals (Cu, Cd, Pb, Zn, Fe, Ca, and Mg) and six water-quality parameters (Acidity, PO4 (3-), SO4 (2-), NO3 (-) (,) Cl-, and pH) were investigated in DRHRW sampled from 12 sampling points each from Ibadan (residential) and Lagos (industrial) environments, Nigeria. The results of these parameters were formulated into membership function fuzzy matrices based on four contamination classifications of high, marginal, low, and poor qualities using regulatory limits as criteria. The products membership function matrices and weight matrices generated indices that classified the degree of anthropogenic activity impact on the sites. Results of FCA classified the DRHRW from residential environment as between high and marginal quality, whereas DRHRW from industrial environment is classified between marginal and low quality. Lead and Cd were major contaminants of concern found in these harvested water.