Purpose
The non-structural embankment repair projects at Locks and Dams (LD) 2 through 10 will address restoring embankments to meet current design standards. Most dam embankments are currently protected from the erosive forces of water by a layer of riprap placed along the embankment’s length. When the riprap eventually erodes, the embankment itself will erode if more protection is not added.
Location
Upper Mississippi Locks and Dams 2 through 10.
Description
The U.S. Army Corps of Engineers has designed and placed berms and small islands to assist in reducing wave action and wind fetch within pools created by the locks and dams. Reducing these forces increases the longevity of the embankment protections. An example of this repair is the embankment at Lock and Dam 4 (photo above), where the Corps placed dredge material to create a berm for terrestrial habitat.
Status
For the programmatic review of the non-structural embankments adjacent to structures, the Corps prepared a draft problem appraisal report (PAR). The PAR has three goals:
- Identify programmatic rehabilitation and repair needs,
- Programmatically evaluate and screen alternative measures, and
- Prioritize locks and dams for funding and subsequent repairs.
After the PAR, the Corps completes feasibility reports with integrated environmental assessments for individual projects identified during the PAR.
The Corps initiated the first feasibility report at Lock and Dam 2 in fiscal year 2017 and completed the report in fiscal year 2021. Plans, specifications and a contract award for a protective island upstream of Lock and Dam 2 will be completed early in fiscal year 2023. Contract award for the Lock and Dam 2 island is contingent upon receipt of funds. The estimated cost is $5.6 million.
Additional non-structural embankment repair at the other locks and dams will continue in future fiscal years.
Authority
Congress authorized the Upper Mississippi River 9-Foot Channel Navigation Project as part of the River and Harbor Act approved July 3, 1930.
Funding
Embankment rehabilitation work at the locks and dams is completely funded by the federal government.
FY 2022:
No funds expected