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<br />The Traditional River
<br />Platte
<br />i "Platte" is the French word for flat-an honest translation by French explorers of
<br />- "nebraska", the Omaha Indian name for the broad shallow braided river (Matter 1969, p. 6). The
<br />North Fork of the Platte is 618 miles long, while the South Fork extends 424 miles before the
<br />? two combine just east of North Platte, Nebraska to form the 310-mile main stem. Measured by
<br />? volume at the mouth, the Platte River delivers an average of 5,980 cubic feet per second (cfs) to
<br />- the Missouri, a pittance compared to rivers such as the Ohio (281,000 cfs), or the Missouri
<br />- (76,200). Approximately 90,000 square miles in Colorado, Wyoming, and Nebraska contribute
<br />surface runoff and groundwater to the Platte River, yielding an average annual flow of 5,051,000
<br />? acre feet to the Missouri (Platte River EIS Team 2000).
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<br />• Near the continental divide Colorado and Wyoming mountain snowpack thaws into
<br />- rivulets gathering into plunging streams that flow through rough canyons and then abruptly run
<br />out on flat prairie where water settles into wide beds, which, well before the Nebraska borders,
<br />? drop only at an average rate of 7 feet per mile (Ring 1999, p.13). Plains channels are typically
<br />? broad, braided, and sandy, with low banks, sparse woody vegetation and high sediment loads
<br />? (Wohl, McConnell, Skinner, and Stenzel 1998); (Eschner, Hadley, and Cromley 1981). Average
<br />? annual rainfall slowly increases as one travels from west to east, from about 12 inches to 20 at
<br />the 98`t' meridian two thirds across Nebraska. Aridity dictated a river bounded by a short-grass
<br />? plains landscape of buffalo and blue grama grasses.
<br />Prior to European settlement, the natural flow pattern consisted of a spring rise
<br />(beginning in March), extending to a peak in late May or June, and then a sharp decline in late
<br />June into summer, fall, and winter months. Spring and early summer floods cleared vegetation
<br />from sandbars, islands, and river banks, and distributed sediment across a wide path. In the view
<br />of most analysts, channels had only small and infrequently distributed clumps of green ash,
<br />plains cottonwood, box-elder, and willows growing along the banks. A mile wide in some
<br />places, the river was described as a burlesque of rivers, braided with islands, studded with
<br />sandbars. Early travelers complained that the Platte could not be ferried for lack of water, and
<br />could not be bridged for lack of timber (Matter 1969: 239). When Fremont descended the North
<br />Platte in early September 1845, he attempted to float a bull boat with a draft of four inches and,
<br />after dragging it on the sands for three to four miles, abandoned the boat entirely (Simons and
<br />Associates Inc. 2000).
<br />There has been vigorous debate among analysts as to the extent of the riparian forest in
<br />the pre-European settlement Platte river. The dominant view has been that the pre-settlement
<br />Platte was mostly an open non-wooded prairie river dominated by sandbars and non-arboreal
<br />vegetation (Currier, Lingle, and Walker 1985) (Currier 2000). However, using historical
<br />accounts of the river and early settlers and early General Land Office Survey information, that
<br />mostly treeless view of the Platte has been challenged (Johnson 1994; Johnson 2000). This view
<br />has pictured the traditional Platte as a river with an abundance of trees and riverine forest that
<br />was cleared during exploration and early settlement. The "openness" reported by observers of
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