The monitoring of aquatic ecosystems including important rivers, often limited in the African setting, is essential for the sustainable provision of aquatic resources. Mohokare River, a major tributary of the Senqu-Orange River, is under threat of pollution from Maseru City, the most industrialised area in Lesotho. This study investigated the impact of Maseru City on Mohokare River by assessing the situational physico-chemical, biochemical and microbiological quality of the river. The study employed standard methods to assess nitrate and phosphate concentrations, total suspended solids, total dissolved solids, electrical conductivity, turbidity, pH, temperature, dissolved oxygen content, biochemical oxygen demand and coliforms. Overall, all water quality indicators, except pH, changed significantly along the river. Turbidity, phosphate and coliforms were above the expected levels. The findings indicate that the water quality is affected by anthropogenic activities associated with industries, agriculture and settlements of the Maseru City. Water from the assessed segment and downstream of the river can be a potential threat to human health, animals and aquatic life. To protect the ecosystem integrity of Mohokare River, the implementation of environmental policies should be strengthened. This study can provide valuable information to municipal water providers in the riparian communities, policy makers, aquatic ecosystem researchers and public health researchers.
