ABSTRACT
Ovia River serves different domestic purposes for inhabitants of the area which includes drinking, bathing, and waste disposal. Despite this, the river constantly receives input from human as a result of anthropogenic activities that take place in the catchment area. To assess the level of pollution of the river, three sampling stations were surveyed for physico-chemical characteristics of water and phytoplankton abundance from October to December 2021. Results of the physico-chemical parameters of the study were 28.89±0.25°C, 7.01±0.70, 42.33±16.23µS/cm, 7.80±0.35mg/L, 3.95±0.13mg/L, 81.39±7.61mg/L, for water temperature, pH, electrical conductivity, dissolved oxygen, biochemical oxygen demand and total alkalinity respectively. While other parameters such as calcium, sulphate, total hardness, colour, total dissolved solids and total suspended solids ranged from 2-12±1.42mg/L, 1-11±0.47mg/L, 10-35±5.33mg/L, 2-37±4.70PtCoU, 14-54±9.15mg/L and 3-49±5.71mg/L respectively which fell within the acceptable limits of WHO and SON. Phytoplankton studies revealed a total of 107 taxa among four divisions in the order: Bacillariophyta> Chlorophyta> Cyanophyta> Euglenophyta, with Bacillariophyta accounting for 52.3%, of the flora. Chlorophyta, Cyanophyta and Euglenophyta contributing 33.64%, 11.21% and 2.80% respectively. Using Palmer’s algal pollution index, about 72% of the index fell within the range of less organic polluted species, while 11% and 17% fell within moderate and no organic pollution range respectively.
