Groundwater quality and its suitability for domestic and agricultural uses in Wilberforce island, southern Nigeria

Ks Okiongbo,Ei Ohiman

doi:10.4314/gjgs.v12i1.1

Abstract

Hydrogeochemical analysis of groundwater samples collected from parts of the Wilberforce Island in Bayelsa State, Southern Nigeria has been carried out in an attempt to assess the suitability of the groundwater for domestic and agricultural purposes in the area. The study was based on thirteen groundwater samples collected from domestic boreholes analysed for some physical and chemical constituents including electrical conductance, pH, total dissolved solids (TDS), alkalinity, hardness, Na + , K + , Ca 2+ , Mg 2+ , Fe, Cl - , SO 4 2- , NO - 3 , and HCO 3 . The quality of the groundwater samples was evaluated with reference to WHO standards. The results obtained showed that the concentration of dissolved major cations and anions in the groundwater vary spatially and mass abundance was in the order of: Ca 2+ > Na + > Fe >K + > Mg 2+ for cations and Cl - > HCO 3 - > CO 3 - - > NO 3 - > SO 4 2- for anions. The concentration of these ions as well as such parameters as total hardness and TDS are below the World Health Organisation (WHO) standard for domestic uses of water in over 80% of the samples. However, iron was over 3000% higher than the WHO permissible limits. The groundwater in the area is fresh, high salinity and low sodium in nature. Ca – HCO 3 and Ca – Cl – HCO 3 are the dominant hydrochemical facies of the study area. Alkali earths metals (Ca 2+ and Mg 2+ ) and strong acids (Cl - and SO 4 2- ) are slightly dominating over the alkali metals (Na + and K + ) and weak acid anions (HCO 3 - and CO 3 2- ).

Highlights

The Wilberforce Island in Bayelsa state is the host of the prestigious state owned Niger Delta University, and a fast growing urban centre
Despite the importance of groundwater in the Wilberforce Island, there had been no detailed characterisation of the groundwater quality, and little is known about the natural phenomena that govern the chemical composition of groundwater or anthropogenic factors that presently affect them
Assessment of the groundwater suitability for domestic uses and domestic consumption was evaluated by comparing the hydrochemical parameters of the groundwater in the study area with the prescribed specification of World Health Organisation (WHO 2004)

Summary

Introduction

The Wilberforce Island in Bayelsa state is the host of the prestigious state owned Niger Delta University, and a fast growing urban centre. The Island lacks municipal water supply, groundwater is the major and preferred source of drinking water for over 95% of the residents. This has placed a high demand on the groundwater resource on the Island. Despite the importance of groundwater in the Wilberforce Island, there had been no detailed characterisation of the groundwater quality, and little is known about the natural phenomena that govern the chemical composition of groundwater or anthropogenic factors that presently affect them. The suitability of groundwater for domestic use, industrial and irrigation purposes depends on its hydrogeochemical composition (Singh and Singh 2008), and that can be indicative of its origin and history of the passage through the underground materials with which the water has been in contact (Prasana et al 2011). The interaction of all the factors leads to various water types of different qualities

Methods

Results

Conclusion