Physiochemical characteristics and heavy metal levels of water from hand dug wells in Ikiran-Ile, Akoko Edo Local Government Area, Edo State, Nigeria

Abstract

Groundwater is water beneath the surface of the earth. The primary source is precipitation from rain, snow, and hail. Groundwater commonly occurs as water that fills pore spaces between mineral or rock grains in sediments and sedimentary rocks. This study is to evaluate the physiochemical characteristics and selected heavy metal levels of Water from Hand Dug Wells in Ikiran-Ile in Akoko Edo Local Government Area of Edo State, Nigeria. A total of twenty (20) water samples were collected in very clean containers from twenty (20) locations in Ikiran-Ile village, and taken to the laboratory immediately for physical, chemical and heavy metal analysis using standard laboratory techniques. Results from the study, shows that the ground water is odorless and tasteless, soft to moderately hard, contains free carbon oxide and alkalinity is due to bicarbonate ions. Sodium (Na), chloride (Cl), Iron (Fe) bicarbonates (HC0₃) calcium (Ca²⁺) potassium (K⁺), and Magnesium (Mg²⁺) are the most abundant of the dissolved cations in the water, while lead (Pb), chromium (Cr) and zinc (Zn) have high concentration levels. These cations exceeded the W.H.O recommended limits. Dissolved solids in the samples are below recommended maximum limits by W.H.O. Samples also showed high bacteria load which primarily originated from effluent discharge from pit toilets and waste dumps and can constitute health risk on ingestion. Highly populated areas have groundwater with high concentration of dissolved ions and the converse for areas of low population. From the results of the analysis, conclusion is drawn to the fact that, the groundwater chemistry in the study area has been influenced greatly by human activities than the bedrock geology of the area. It is therefore recommended that well location should be at least, 30m away from any source of contamination such as soak-ways, adequate treatment must be given to well water such as chlorination, boiling to destroy any bacteria and filtration to remove all unwanted/undesirable constituents that may be present, and a policy on land use planning and urban development to guard against indiscriminate setting of wells within the centre of the village should be established. This study has been able to enhance sustainable water development, since the health of inhabitants in a community depends to a large extent on the quality of groundwater supply.

Keywords: Groundwater, Physiochemical, Heavy metals, Ikiran-Ile