Omaha, NE – A draft supplemental environmental assessment (EA) for operation and maintenance repairs at Middle Decatur Bend is currently available for public review. The draft supplemental EA evaluates the environmental impacts of repairing a water control structure (WCS10) that was damaged during high water in 2018. WCS10 is located along Missouri River Mile 687.25 in Monona County, Iowa and maintains the lake elevations for Decatur Bend Lake located immediately upstream of the structure.
In August 2018, high precipitation caused the Missouri River to flank WCS10. As a result of damage to the structure and resultant change in the river flow pattern near the structure, WSC10 has lost its ability to maintain the lake elevations and poses the potential for damage to dike 739.75, located downstream. The Decatur Bend Project was constructed in 2003 to establish habitat for fish and wildlife that was lost as a result of the Missouri River Bank Stabilization and Navigation Project.
Proposed repairs include placing 175 linear feet (LF) of riprap immediately south of WSC10 to create a dike across the existing outlet, a 190-LF rock core levee across the berm of the outlet and a windrow of stone to tie the dike and berm together to provide protection against potential future overtopping events. The proposed repairs are necessary to ensure WSC10 has the ability to maintain water levels in the Decatur Bend Habitat Project.
The public is encouraged to provide comments on the draft supplemental environmental assessment which is available for download at www.nwo.usace.army.mil/Missions/Civil-Works/Planning/Project-Reports/. Comments can be mailed to: U.S. Army Corps of Engineers, Omaha District; CENWO-PMA-C; ATTN: Middle Decatur Bend Supplemental EA; 1616 Capitol Avenue; Omaha, NE 68102-4901. Comments can also be emailed to: cenwo-planning@usace.army.mil. Comments must be postmarked or received no later than January 28, 2019.
This draft supplemental EA is consistent with the National Environmental Policy Act of 1969 (NEPA), as amended, the Council on Environmental Quality’s (CEQ) regulations for implementing NEPA (40 CFR 1500-1508), the Corps’ regulations for implementing NEPA (33 CFR 325 and Engineering Regulation 200-2-2) and other applicable environmental laws and regulations.
Release no. 18-088