Abstract:The 8.0-magnitude Wenchuan earthquake triggered huge landslides that blocked rivers and created more than 34 quake lakes including the Tangjiashan one on the Jianjiang River in Beichuan County.More than 17 quake lakes were in moderately dangerous situations and needed to be tackled in emergency for hazards relief.The Digital Watershed Model(DWM) and hydrodynamic models developed at Tsinghua University were adopted for quickly forecasting the incoming flow discharge and dam-breach processes of the Tangjiashan Quake Lake.Dam break scenarios of typical quake lakes were also simulated for outburst flood routing in downstream rivers and the simulation results were used for the design of emergency treatment plans.To meet the need of emergency forecasting and treatment of quake lakes in areas with limited data,it is desirable to set up an integrated modeling system that functions as hydrological forecasting,dam breach analysis,inundation analysis,and optimal decision of engineering measures.