Emergency disposal of water in earthquake-induced dammed lakes must adequately utilize fundamental data for efficient decision making.This paper presents a comparative study of the rapid estimation of downstream flood risks induced by dammed lakes using the Muskingum and Hydrodynamics methods combined with remote sensing,DEM,hydrologic data,and GIS techniques.Both methods were used to calculate the downstream potential impact area from the Tangjiashan dammed lake when the dam-break water level reached 690 m...