This dataset represents the average level of conventional treatment at tap water treatment plants in Jilin, covering the full production process of tap water from raw water abstraction to plant effluent, specifically including water abstraction, coagulation and sedimentation, filtration, disinfection, water storage and water conveyance, as well as other conventional treatment units. The dataset focuses on documenting the use of chemicals such as coagulants, disinfectants and sludge-treatment agents, as well as electricity consumption, water-plant construction and maintenance, and related items. The data are sourced from statistical yearbooks.