Signatures of contamination, corrosivity and scaling in natural waters from a fast-developing suburb (Nigeria): insights into their suitability for industrial purposes

Abstract

Ojoto and its environs are a fast-growing suburb with many emerging industries. In this area, inhabitants and industrialists exclusively rely on both surface and groundwater for their domestic and industrial purposes such that there is the need to assess the drinking quality, corrosivity and scaling coefficients of the water resources. This need formed the focus of this current work. Water samples from springs, streams, hand-dug wells and boreholes were subjected to physicochemical, corrosivity and scaling examinations. Temperature was in the range of 23–29 °C. pH analysis revealed that the samples are acidic in nature. Values of Ca, Cl, HCO3, SO4, TDS, EC, TH and Zn were below their respective maximum allowable limits for drinking water. However, Fe and Pb contaminations were observed in some samples. Based on integrated water quality index, all the samples are classified as unsuitable for drinking. However, synthetic pollution index revealed that about 50% of the samples are suitable for human consumption. Corrosivity and scaling evaluation indices such as chloride–sulfate mass ratio, Revelle index, Larson–Skold index, Ryznar stability index, Langelier index, aggressive index and Puckorius scaling index indicated that the majority of the samples have low to insignificant scaling potentials. Nevertheless, majority of the indices indicated that the natural waters have very significant corrosive tendencies and as such portend further deterioration of both domestic and industrial water quality and distribution systems in future.