Study on the proportion and flow path of Yangtze River water diversion into Taihu Lake

Abstract The purpose of this study is to quantify the proportion and flow path of the water diversion from Yangtze River (YRD) into Taihu Lake. Based on the analysis of rainfall and data of Taihu basin in the recent 30 years, a 1-D hydrodynamic model of the main inflow river network area of Taihu basin was constructed, coupled the convection-diffusion model with conservative material, the characteristics of YRD and the water inflow into Taihu Lake (WITL) in three typical years were calculated. The results show that the YRD has shown a significant upward trend in the past 30 years, accounting for 26.4, 35.6 and 42% of the total WITL in three typical years of wet, normal and dry conditions respectively. From the perspective of space, Taige River is the largest river in the western part of the lake that is affected by the river diversion (35%–72%), and Wuxi River is the smallest (1–3%). In addition, the primary flow path of YRD to Taihu Lake was through the Wuyi River and Lake Gehu from the water diversion station west of the Zao River.