Assessment of Nutrients Levels in Groundwater within the Lower Pra Basin of Ghana

M K Dorleku,D Nukpezah,A O Affum,C K Tay

doi:10.4314/gjs.v60i1.3

Abstract

The level of concentration of nitrates, phosphates, and sulphates was determined in groundwater within the Pra Basin to ascertain the degree of anthropogenic influence via the application of fertilizer and other agro-chemical to farmlands by farmers. Sixty-five (65) boreholes in forty-five (45) communities were analysed between January and April 2012 to cover the dry season and between June and October 2012 to cover the wet season. The results show that nitrate for both seasons range between 0.011 mg/l and 5.01 mg/l and therefore within the WHO (2006) guideline value of 10 mg/l, whilst that of phosphate range between 0.01 mg/l and 3.08 mg/l and therefore outside the USEPA guideline value of 2.5 mg/l. Sulphate recorded a range between 1.60 and 96.2 mg/l and therefore within the WHO (2006) guideline value of 250 mg/l. The concentration levels of the two nutrients of the parameters, nitrates and phosphate were correlated against borehole depth and the results show a weak positive and negative correlation for nitrate and phosphate respectively. There was thus, an indication that the levels of all parameters, nitrate, phosphate and sulphate are not yet a threat to groundwater in the basin.

Highlights

The safety and quality of water are essential, especially to human health, agriculture, aquaculture, industry and all forms of life
The results show that the mean concentration of the parameters as compared to the WHO(2006) guideline values are low and do not pose an immediate threat to human health
Natural geologic sources might have a greater influence on concentrations in groundwater than anthropogenic sources

Summary

Introduction

The safety and quality of water are essential, especially to human health, agriculture, aquaculture, industry and all forms of life. Aquifer characteristics Borehole depths of the study area are generally shallow ranging between 30 to 96 metres, with a mean value of 44.42m. Borehole yield is generally low and largely variable, ranging from 0.4 to 51.7 m3h-1 and mean value of 4.55 m3h-1 with schist and granite aquifers having relatively higher yields (Tay et al, 2013, Dorleku 2013).

Results

Conclusion