Abstract: The Middle Route of South-to-North Water Transfer Project (MRP) is a large-scale project benefiting the whole nation, and also a key measure of China's future energy development strategy. This paper describes a classification and grading system of water pollution emergencies in MRP based on a driving-pressure-state-impact-responses (DPSIR) framework. First, we construct an evaluation index system using 16 indicators selected to reflect the driving force, pressure, state, influence and response of different regions, and divide them into a static system and a dynamic system by the characteristics of the indicators. Then, their values are specified through a procedure of standardized assignment that considers the overall conditions and requirements of MRP, and the risk level of water pollution emergencies is determined using an analytical hierarchy procedure and a coordinated social development model. Finally, a classification system is described and verified using a case study of the canal bridge S237.

Key words: Middle Route of South-to-North Water Transfer Project, DPSIR framework, water pollution emergencies, coordinated social development