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I I I I I I I I I I I I I I I I I I I oats blue joint reed grass big bluestem indiangrass sweet clover Avena sp. Calama~rostis canadensis AndrQPo~on 2erardi Sor~hastrum nutans Melilotus sp. Alternative C is the only alternative for which reforestation is proposed. Two different habitat types, riparian and bottomland hardwoods, would be established. On the 246 acres that would be reforested in bottomland hardwoods the following speCies would be planted: gray dogwood swamp white oak sycamore basswood silver maple boxelder greenash Cornus foemina racemosa Quercus biocolor Platanus occidentalis IililI americana ~ saccharinum ~ negundo Fraxinus pennsylvanica Of the 105 acres that would be planted in riparian forest, only two species would be utilized, black willow fSalix ~ and cottonwood (Populus deltoides), a. Alternative A - Flow-Through Chute: This alternative consists of constructing a pilot channel through the Langdon Bend right overbank area, This would allow a portion of the main channel flow to be diverted across the inside of the river bend and through the existing historic chute area. The pilot channel would have active flow most of the year, except during periods of extremely low river flow, below approximately 18,000 cfs. The pilot channel is intended to assist in restoring large river fIsheries habitat by developing into a wide shallow chute, with lower velocities, that will meander through the overbank to some extent. Three pilot channels, with bottom widths oflO, 25, and 50 feet and side slopes of2H to IV, were evaluated. The 25- and 50-foot widths were evaluated as potential methods to accelerate the development of the ultimate chute channel. Inlet and outlet channel structures would be constructed to allow water flow and fIsh and other aquatic species to pass into and out of the chute. Existing river revetments and closure dikes would be lowered as necessary, and grade control structures would be constructed along the pilot channel flow path to prevent excessive scour and deposition. The grade control structures would also help to prevent excessive lateral migration of the chute channel. Excavated material from construction of the pilot channel would be disposed of adjacent to the pilot channel. None of the material would be hauled off-site or disposed of on the landward side of the Federal Levee, As the pilot channel scours during the development of an ultimate chute channel, some of the scoured material would be washed out to the Missouri River, and some would be deposited in the chute channel itself in the form of sand bars, The disposal area along 26