Taking the hydropower development Sandaogou river mainstream for example,the paper explored the impact of dewatering section on the living of local residents and the surrounding ecological environment, and finally proposed a more reasonable program. Through analyzing the influence of eighth grade hydropower station and thirteenth Jiajiayingzi second grade hydropower station on the living of local residents and the surrounding ecological environment, it presented a technical feasible, economic rational alternative program.The result can provide reference for the development of similar projects.