Dams Snake River

many factors have influenced construction of dams along snake river. total of fifteen dams have been constructed along snake river multitude of different purposes, headwaters in rocky mountains mouth on lake wallula, slackwater reservoir formed behind mcnary dam on columbia river. dams on snake can grouped 3 major categories. headwaters beginning of hells canyon, many small dams block snake provide irrigation water. between here , hells canyon, first dam on snake, swan falls dam, built in 1901. in hells canyon, cascade of dams produce hydroelectricity river s lofty decrease in elevation on comparatively small distance. finally, third cascade of dams, hells canyon mouth, facilitates navigation. many different government , private agencies have worked build dams on snake river, serve important purpose people living in snake s drainage basin , trade of agricultural products pacific seaports.

the minidoka irrigation project of u.s. bureau of reclamation, created passage of reclamation act of 1902, involved diversion of snake river water snake river plain upstream of shoshone falls in order irrigate approximately 1,100,000 acres (4,500 km) in snake river plain , store 4,100,000 acre feet (5.1 km) of water in snake river reservoirs. first studies irrigation in plain conducted united states geological survey in late 19th century, , project authorized on april 23, 1904. first dam constructed project minidoka dam in 1904; power plant began operating in 1909, producing 7 mw of electricity. capacity revised 20 mw in 1993. however, minidoka dam not dam constructed project. far upstream jackson lake in wyoming, jackson lake dam built in 1907 raise lake level providing additional water storage dry years. american falls dam, upstream of minidoka, completed in 1927 , replaced in 1978. dams constructed above shoshone falls, historical upriver limit of salmon , total barrier boats , ships, no provisions made fish passage or navigation. several other irrigation dams built - including twin falls dam , palisades dam.

brownlee dam, uppermost dam of hells canyon project

the hells canyon project built , maintained idaho power company starting in 1940s, , second of 3 major water projects on river. 3 dams of project, brownlee dam, oxbow dam , hells canyon dam, located in upper hells canyon. 3 dams power generation , flood control, , not have fish passage or navigation locks. brownlee dam, upriver dam, constructed in 1959, , generates 728 mw of power. oxbow dam, second dam in project, built in 1961 , generates 220 mw. dam named 3-mile-wide (4.8 km) bend in snake river, shaped oxbow, although not oxbow lake. hells canyon dam last , downriver of three, constructed in 1967 , generates 450 mw.

downriver of hells canyon lower snake river project, authorized rivers , harbors act of 1945, created u.s. army corps of engineers create navigable channel on snake river mouth beginning of hells canyon. these dams are, in downstream order: lower granite lock , dam, little goose lock , dam, lower monumental lock , dam, , ice harbor lock , dam. dredging work done throughout length of navigation channel facilitate ship passage. these dams form cascade of reservoirs no stretches of free-flowing river in between. below ice harbor dam lake wallula, formed construction of mcnary dam on columbia river. (mcnary dam not part of lower snake river project.) above lower granite dam, river channel lewiston johnson bar, below hells canyon, maintained jet-boats section rugged ships. these dams have been proposed removal, , if removed, largest dam removal project ever undertaken in united states. removal has been proposed on grounds restore salmon runs lower snake river , clearwater river , other smaller tributaries. idaho s snake river once teemed sockeye salmon. however, there no wild sockeye salmon left in river due number of factors.

there many reasons why sockeye salmon in snake river reduced in number. 1 reason river runs through 3 different states, , on 1,000 miles (1,600 km) long. salmon swimming upstream in river faced predators , dams. snake river has fifteen dams , extremely difficult salmon access because of hydroelectric dams. hell s canyon dam blocks passage entire upper snake river. grand coulee dam blocks spawning grounds famous june hogs (legendary chinook salmon weighed on 100 pounds [45 kg]).

between 1985 , 2007, average of 18 sockeye salmon returned idaho each year. serious conservation efforts wildlife biologists , fish hatcheries have captured few remaining wild sockeye salmon, collected sperm , eggs, , in laboratory, have them spawn. instead of spawning naturally, these sockeye begin lives in incubator in fishery biologist s laboratory. these baby salmon transported ship, bypassing dams. (the dams can hurt juvenile baby sockeye salmon powerful tides , currents, suck baby salmon down.) conservation effort has helped salmon recover, destruction of old, outdated dams, such lewiston dam on clearwater river, tributary of snake. after destroying dam, salmon populations noticeably recovered.

another interesting recovery method conservationists , biologists using called fish transportation. since many juvenile salmon perish @ each dam while swimming out ocean, massive ships filter , collect these baby salmon size , take them out ocean ride, can guaranteed make alive saltwater. method raises controversy effectiveness , costs, since method extremely expensive, costing $15 million. similar method transport fish across dams fish gun method. engineers @ whooshh innovations have developed whooshh fish transport system literally collects salmon , shoots them above dam @ high speed in effort them across dams.

overall, these combined efforts have had success. in summer of 2006, snake river reportedly had 3 sockeye salmon returned spawning grounds. in summer of 2013, more 13,000 sockeye salmon returned spawning grounds.

the little goose lock , dam