自20世纪30年代起,美国陆军工程师团建设并运行哥伦比亚河及斯内克河下游的8座梯级水电站,这些水电站通过各种工程措施维持鱼类洄游通道。
Since 1930s the US Army Corps of Engineers has built and operated a string of 8 hydropower stations along the lower Columbia and Snake River and adult and juvenile salmon passages are maintained with various measures .