This dataset represents the average level of advanced treatment at tap water treatment plants in Guangdong, 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, and also covering advanced treatment stages such as activated-carbon adsorption, ozone oxidation and membrane filtration. 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.