Abstract: The water supply capacity of a certain water treatment plant in the Central Plains region falls far short of its designed scale, and the quality of the effluent experiences significant fluctuations. As a result, it can no longer meet the local demand for stable water supply, thus necessitating an upgrade and retrofit. Through water quality analysis, the removal of iron and manganese was identified as the primary treatment objective. After on-site inspections and in combination with past engineering expertise, an iron and manganese removal process plan was formulated. It discussed the selection of aeration and oxygenation devices as well as iron and manganese removal filters. Moreover, an iron and manganese removal unit process and an automated control system were designed, followed by the operation and commissioning of the equipment.