FLOOD04472

• County: Statewide
• Community: Nemaha County Nebraska
• Stream Name: Missouri River Miles 532.4-528.9
• Basin: Statewide
• Title: Langdon Bend Habitat Restoration/Preservation Project Volume 1
• Date: 6/1/1995
• Prepared For: US Army Corps of Engineers
• Prepared By: Greenhorne & O'Mara, Inc.
• Floodplain - Doc Type: Project

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e. Resource Problems and Opportunities: Langdon Bend is located east of the
Town of Nemaha in Nemaha County, Nebraska, along the right bank of the Missouri River. It
is comprised of approximately 921 acres of land purchased by the Corps and a 133-acre easement
owned by the Nebraska Public Power District (NPPD). The area included in this study (herein
referred to as the "project site" or "site") comprises 725 acres located east of the Federal Levee.
The main channel of the Missouri River, Miles 532.4 to 528.9, borders the project site on the
east. The site consists of fannland, vegetated wetlands, and uplands. Most of the lands required
for this project are currently owned by the Corps.

Historically, the Missouri River at Langdon Bend was much wider and significantly more
diverse than the present day morphology. The pre-channelized 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 Langdon Bend was much wider in the 1930' 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. Alteration of the natural hydrograph
also occurred due to the regulation of water flow at upstream dams along the river and its
tributaries. The overbank area east of the Federal Levee is now hydraulically disconnected from
the main channel except during periods of very high river stage, The project site is dry most of
the year and the majority has been farmed, This situation is a direct result of the construction,
operation, maintenance, and management of the channel stabilization project, and the upstream
dam projects.

Observation of historic maps shows that the course and morphology of the Missouri River
naturally changed over time. Present day evidence df the historical flow paths is seen in the form
of predominantly dry chute channel beds which are located along the right overbank at Langdon
Bend. The Langdon Bend site currently holds water in low elevation areas during and after high
stage events on the Missouri River. The chute channels do not currently provide for large river
fisheries habitat or spawning areas. A high potential exists to provide a hydraulic reconnection
to the Missouri River for fisheries habitat, and to ensure a more permanent and consistent water
supply to the project site.

f. Project Goals and Objectives: This component of the Missouri River Fish and
Wildlife Mitigation Project is intended to restore large-river habitat and associated chutes, and
wetlands in the floodplain adjacent to the main channel at Langdon Bend. Historically, chutes,
wetlands, backwater areas, sandbars, and other features were important components of the entire
river ecosystem. The project objective is to determine an alternative mitigation procedure that
most closely resembles or maximizes preconstruction habitat values. At Langdon Bend this would
be accomplished by establishing a hydraulic connection to the Missouri River and the floodplain,

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