Spatial and seasonal variations in physico-chemical parameters and the water quality index at the Okhuaihe River in Ikpe Community, Edo State, Nigeria

Abstract

The scarcity of clean water in rural Nigerian communities leads to dependence on streams and rivers which are often polluted by domestic and industrial activities distorting the quality of water. Freshwater ecosystems, which are important for global biodiversity, are constantly burdened with threats from environmental changes as well as human misuse. This study was aimed at investigating the spatial and temporal variations of physico-chemical parameters and the water quality index (WQI) of the Okhuaihe River in Ikpe, Edo state, Nigeria, used for different domestic activities. The study assessed parameters like air and water temperature, pH, electrical conductivity, flow rate, total dissolved solids, phosphate, chloride, iron, zinc, and manganese at four stations over a six-month period. Samples such as air and water temperature and pH were collected and measured in situ, while others were collected using polyethylene bottles and a 250 ml amber bottle for biochemical oxygen demand (BOD5). Results indicated that while some physico-chemical parameters like the width, the flow rate, and phosphate showed considerable differences, most did not differ significantly. Temporally, there were significant seasonal variations in air temperature, electrical conductivity, total dissolved solids, chloride, iron, zinc, and manganese. The WQI calculations showed that the water quality at all stations was within safe limits for human consumption and supported aquatic life. Despite some fluctuations due to seasonal changes and anthropogenic activities, the overall quality remained suitable for domestic use. This underscores the importance of constant monitoring and management of water resources to allay pollution and ensure sustainable water supply in rural communities.