STUDY ON WATER-DIVERSION OF THE DONGHAI AND XIHAI WATERWAYS

摘要

The river networks and channels of the Pearl River Delta connect mutually. The regulations of the river courses and diversion channels are related to the whole water system. Many floods during the 1990s showed that great changes of current characteristics occurred in the river courses of the Pearl River Delta, which aggravated the disaster situation of the local regions. Among the influencing factors, the variation of the diversion ratios of the main river nodes is the most important one. The flow discharge of the DongHai Waterway directly influences (impacts on) the flood water levels of the downstream river reaches (the lower reaches), such as the Xiaolan Waterway, the Jiya Waterway, and so on, and causes the influence of the backwater on the trunk stream of the Beijing River at the same time. Based on the results of the different physical models and the field data of the discharge in 1997 and 2001, the variation law of the diversion ratio of the Donghai Waterway and the Xihai Waterway and its influence on the water lever of the lower reaches are analyzed. Alternative schemes to adjust the diversion ratio are compared, finally the optimized regulation scheme is proposed.