Impacts of the eastern route of the South-to-North Water Diversion Project emergency operation on flooding and drainage in water-receiving areas: an empirical case in China

摘要

The water levels of lakes along the eastern route of theSouth-to-North Water Diversion Project (ER-SNWDP) are expected to risesignificantly and subsequently affect the processes of flood control anddrainage in corresponding lake basins. However, few studies have focused onthe impacts of inter-basin water diversion on the flood control and drainageof water-receiving areas at the lake basin scale. Using MIKE software, thispaper builds a coupled hydrodynamic model to address the existing literaturegap regarding the impacts of inter-basin water diversion on the processes offlood control and drainage in a water-receiving lake basin, and it considersthe many types of hydraulic structures in the model. First, a floodsimulation model was constructed to simulate the complex movement of watertransferred by the ER-SNWDP, by waterlogging in the lakeside area aroundNansi Lake (NL), and water in NL and its tributaries. The ER-SNWDP was alsoconsidered in the model. Second, the model was calibrated and verified withmeasurement data, and the results showed that the model was efficient andpresented a Nash–Sutcliffe efficiency coefficient (NSE) between 0.65 and0.99. Third, the processes of flooding and draining in the lakeside area ofNL were simulated under different water diversion and precipitation values.Finally, the impacts of the emergency operations of the ER-SNWDP on floodcontrol and waterlogging drainage in the lakeside area of NL were analysedbased on the results from the proposed model, and some implications arepresented for the integrated management of inter-basin water diversion andaffected lakes.