Study on Impact of East Route Project of the South-to-North Water Diversion in China

Due to uneven rainfall patterns, water scarcity is plaguing China especially in North China. The South-to-North Water Diversion (SNWD) project is the biggest hydraulic project ever designed worldwide. The East Route's (ER) mission is to withdraw water from Jiangdu at downstream section of Yangtze River. Under the Sino-Italy cooperation framework in the field of environmental protection, the SWIMER project — the Sustainable Water Integrated Management of the East Route of SNWD was implemented from 2004 to 2006. This paper briefly introduces the general technical framework of the SWIMER project and focuses on the tasks of ROW AS model — Rules-based Objected-oriented Water Allocation Simulation Model. The core work of SWIMER is to develop an integrated water management tool for the water supply area of the East Route by coupling water allocation model, socio-economic model and climate change model. Through iterate application of the ROWAS model, various allocation scenarios of diverted water are provided to the socio-economic model for optimization. The coupling approach is innovative and successfully applied in the study. The major conclusions are: 1) the implementation of the SNWD East Route project will largely contribute to reduce water stress in the area; 2) the water shortages will diminish and water savings will be realised from the exploitation of the groundwater resources; 3) the optimized allocation of the diverted water resources is compatible with the structural and operational constrains of the water diversion network under average and extreme drought conditions; and 4) an integrated management of the East Route project needs a centralised instrument capable of controlling the diverted water resources, that could be built on the basis of the models developed under the SWIMER project.