Project Reports

Draft Supplemental EA - Middle Decatur Bend (Phase III)

Published Dec. 31, 2018
Expiration date: 1/28/2019

Summary: 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.

Geographic Scope: Missouri River Mile 687.25 in Monona County, Iowa

Decision/Date: Made following close of public comment period