and most downriver of the three. It was constructed in 1967 and generates 450 MW. Downriver of Hells Canyon is the Lower Snake River Project, authorized by the Rivers and Harbors Act of 1945 for the U.S. Army Corps of Engineers to create a navigable channel on the Snake River from its mouth to the beginning of Hells Canyon. These dams are, from upstream to downstream: Lower Granite Lock and Dam, Little Goose Lock and Dam, Lower Monumental Lock and Dam, and Ice Harbor Lock and Dam. Dredging work was also done throughout the length of the navigation channel to facilitate ship passage. These dams form a cascade of reservoirs with no stretches of free-flowing river in between. Immediately below Ice Harbor Dam is Lake Wallula, formed by the construction of the McNary Dam on the Columbia River. (McNary Dam is not part of the Lower Snake River Project.) Above Lower Granite Dam, the river channel from Lewiston to Johnson Bar, just below Hells Canyon, is also maintained for jet-boats as this section is too rugged for ships. These dams have been proposed for removal, and if they were to be removed, it would be the largest dam removal project ever undertaken in the United States. The removal has been proposed on the grounds that it would restore salmon runs to the lower Snake River and the Clearwater River and other smaller tributaries. Idaho's Snake river once teemed with sockeye salmon. However, there are almost no wild sockeye salmon left in the river due to a number of factors. Sockeye Salmon are reduced in number on this river that runs through three different states and is over long. Salmon swimming upstream in this river are faced with predators and dams. The Snake River has fifteen dams and is extremely difficult for salmon to access because of hydroelectric dams. Hells Canyon Dam blocks passage to the entire upper Snake River. Between 1985 and 2007, only an average of 18 sockeye salmon returned to Idaho each year. Serious conservation efforts by wildlife biologists and fish hatcheries have captured the few remaining wild sockeye salmon, collected their sperm and eggs, and in a laboratory, have them spawn. Instead of spawning naturally, these sockeye begin their lives in an incubator in a hatchery. These baby salmon then are transported by ship, bypassing the dams. (The dams can hurt juvenile baby sockeye salmon with their