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I I I I I I I I I I I I I I I I I I I I e. Resource Problems and Opportunities: The California Bend State Wildlife Refuge (herein referred to as the "project site" or "site") comprises approximately 410 acres of land located three miles northeast of Blair, Nebraska, in Harrison County, Iowa along the left bank of the Missouri River. The main channel of the Missouri River, Miles 649.5 to 651.0, borders the project site on the west. The site consists of vegetated wetlands, backwater areas, and uplands. The lands required for this project are currently owned by the State of Iowa. Historically, the Missouri River at California Bend was much wider and significantly more diverse than the present day morphology. The pre-channelization and pre-dam river was characterized by multiple channels which were separated by sand bars, mud flats, willow bars, and timbered islands. A diverse morphology was maintained by annual periods of high discharge. The cross-section of the Missouri River at California Bend was much wider in the 1920's. This pre-control cross-section provided a diverse and rich environment which was important to adjacent terrestrial habitats and to the spawning, feeding, and rearing of native riverine fish and waterfowl. Subsequent to construction of the Missouri River Bank Stabilization and Navigation Project, the overbank and secondary channels were hydraulically cut off from the main channel by the construction of closure dikes, spur dikes, and revetments. Channelization of the river narrowed the width of the active channel to approximately 600 feet. The overbank area west of the Federal Levee is now hydraulically disconnected from the main channel except for the existing backwater area at the south end of the site. This situation is a direct result of the construction, operation, maintenance, and management of the channel stabilization project. Observation of historic maps shows that the course and morphology of the Missouri River naturally changed over time. Present day evidence of the historical river bed is seen in the form of low-lying vegetated wetlands and open water areas which are located along the left overbank at California Bend. The California Bend site currently holds water in low elevation areas during most of the year, and the entire site would be inundated during high stage events. There are currently no flow-through chute channels to provide for large river fisheries habitat or spawning areas. The potential may exist to provide a hydraulic reconnection to the Missouri River for fisheries habitat or to enhance the existing backwater areas for migratory waterfowl habitat. f. Project Goals and Objectives: This component of the Missouri River Fish and Wildlife Mitigation Project would enhance the value of the floodplain adjacent to the main channel at California Bend for migratory waterfowl. Historically, chutes, wetlands, backwater areas, sandbars, and other features contributed greatly to the entire river ecosystem. The project objective is to determine an alternative mitigation procedure that most closely resembles or maximizes preconstruction habitat values. Within this objective, the primary goal is to enhance migratory waterfowl habitat. This could be accomplished by establishing a more permanent backwater area in the California Bend floodplain area, thereby providing for waterfowl habitat and wetlands enhancement. The selected alternative should also optimize cost and minimize adverse social, economic, and environmental impacts. 3