HYDROCHEMICAL ASSESSMENT OF GROUNDWATER IN IKENYI AREA SOUTHEAST NIGERIA

Abstract

The most resilient and sustainable source of water supply in Ikenyi area is groundwater. Unfortunately, groundwater in the area is plagued by contaminants of geogenic origin which is suspected to be the cause of the frequent occurrence of water borne disease in the area. Hydrochemical analysis of water samples from the area was carried out to identify the key contaminants and their spatial distribution in the area. The work revealed that wells in the area which encountered aquifer between the depths of 16m to 22m are mostly contaminated with heavy metals. The heavy metals with concentration values higher than WHO recommended maximum allowable concentration are Iron, Lead, Zinc, Arsenic and Chromium. While anomalous concentration values for Arsenic and Chromium are recorded in less than 40% of the tested water samples, Iron, Zinc and Lead anomalous concentration values occur in 80% to100% of the samples. Heavy metal anomalies are predominantly in the Northeast of the study area. Water quality index based on the weighted arithmetic index method indicates that the tested groundwater is good to poor in the Southeast, mostly very poor in the west and unfit for consumption in the Northeast. The similarity of the Water quality index map derived from weighted arithmetic index and Heavy metal pollution index demonstrated that the water quality in the study area is driven by the heavy metal anomaly. Given the prevalent heavy metal contamination in the study area, it is imperative to consider a robust water treatment plan in any groundwater development project in the area.