Assessment of Surface and Ground Water Quality of Uruan in Akwa Ibom State of Nigeria

Abstract

The water quality status of rivers, streams, and underground water in Uruan Local Government Area, Nigeria was investigated in this study. Inhabitants of this region depend on these water resources for drinking and other purposes. Water samples were collected from four rivers, nine streams, six boreholes and a well from various points across three study zones in the local government. Standard analytical methods were employed for all analyses and the results are compared with water quality standards of the World Health Organisation (WHO) and the Nigerian Standard for Drinking Water Quality (NSDWQ). Most quality determinands are within WHO guidelines except pH, EC, turbidity, TDS, total coliform, and Fe. The overall ionic dominance pattern for the river, stream, borehole and well follow the same trend Fe>Na>Mn>K and Cl^->NO₃^->NO₂^-. The hygienic condition of the water bodies is found to be poor. High BOD₅, coliform count and BOD₅:NO₃ ratio of river, stream and ground water samples are indicative of organic pollution due to faecal contamination. Multivariate statistical approach [correlation, principal component analysis (PCA), and cluster analysis (CA)] was used to identify interrelationships among physicochemical parameters and the pollution source. PCA reveals 3 extracted principal components (PCs) by river water, 6 PCs each by both stream and ground water; with the sources of pollution either from natural hydro-geochemical processes or anthropogenic pollution, or a combination of both. Based on cluster analysis results, water sample stations are classified into 6 clusters, a pointer to the fact that the clusters are peculiar and different from one another. The results imply that water bodies in Uruan are polluted and pose potential risk to humans. Institution of intervention measures including public awareness campaigns in Uruan local government area is desirable to protect the inhabitants from water-related illnesses and their consequences.

Keywords: River; Stream; Groundwater; Water quality; Organic pollution index; Multivariate analysis