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I I I I I I I I I I I I I II ,I I I I I investigated on a case-by-case basis for their technical feasibility, and may be modified as further planning and design occurs, b. Selection Process: The Hamburg Bend area was selected as the first acquisition/development project in the state of Nebraska after an evaluation of the site, aerial photographs and plans, After preliminary engineering feasibility studies indicated the potential for chute development, the Nebraska Game and Parks Commission (NGPC) nominated and ranked the site as its first choice for planning, design, and construction. Real estate for the project has been obtained from willing sellers, 3. AFFECTED ENVIRONMENT The Missouri River Bank Stabilization and Navigation Project authorized channelization of the Missouri River from Sioux City, Iowa to the confluence with the Mississippi River in 1935, The majority of the work was completed between 1945 and 1965, Rock revetments and pile dikes were used to reduce the wide cross-section of the river by cutting off side channels and shallow sand-bar complexes, Previously wet areas silted in with sediment, and the channel eventually stabilized into a narrow corridor about 600 feet (183 meters) wide. Channelization has altered overbank flooding patterns, isolated the floodplain from the river, and increased water velocities in the channel (Fredrickson and Reid 1990), Prior to channelization, the Missouri River was uncontrolled and meandered across the river valley causing erosion, deposition, and accretion. The channel "consisted of numerous islands, channels, chutes, sandbars, and back-water areas supporting vegetation in various stages of succession. The meander belt consisted of a 606,000-acre area adjacent to the natural channel. This area consisted of successional wetlands and various types of herbaceous and woody habitats, as well as some form of agricultural use. It is estimated that over 500,000 acres of aquatic and terrestrial habitat will have been eliminated from the natural channel and meander belt by the year 2003." (U,S, Army Corps of Engineers 1990). The Missouri River system in its natural state provided a diversity of habitats for fish and wildlife, Historically, it contained large populations of fishes and a diversity of species. These have been affected by the loss of water surface area and habitat. The Missouri River and associated habitats support many mammals, reptiles, amphibians, songbirds, shorebirds, and waterfowl. Channelization has resulted in a general reduction in wildlife numbers due to changes in habitats, An assessment of the existing environment has been completed for this DPR. This assessment included research of existing reports, maps, and aerial photographs, as well as field investigations of Current site conditions. Results of the various investigations are summarized below. a. Physiography and Topography: The Hamburg Bend site is located in the floodplain of the Missouri River and is comprised of alluvial material. This region of Nebraska is part of 7