2017-20672. Record of Decision for Final Supplement I to the Final Environmental Statement, Mississippi River Between the Ohio and Missouri Rivers (Regulating Works), Missouri and Illinois

AGENCY:

Department of the Army, U.S. Army Corps of Engineers, DoD.

ACTION:

Record of Decision.

SUMMARY:

The U.S. Army Corps of Engineers (USACE), St. Louis District, is issuing this notice to advise Federal, state, and local government agencies, affected Tribes, and the public that USACE has signed a Record of Decision (ROD) for Final Supplement I to the Final Environmental Statement, Mississippi River between the Ohio and Missouri Rivers (Regulating Works). The ROD was rendered to declare that, after careful consideration of the purpose of and need for the Regulating Works Project, the analysis contained in Final Supplement I, input from the public, affected Tribes, state and Federal agencies, and other interested parties, and based on the Regulating Works Project's Congressional authority and continued benefit of remaining construction, USACE has determined that the public interest will best be served by implementing the Continue Construction Alternative (hereafter, the Selected Plan).

DATES:

The USACE Mississippi Valley Division Commander, Major General Michael C. Wehr, signed the ROD on August 31, 2017.

ADDRESSES:

U.S. Army Corps of Engineers, Regional Planning and Environmental Division North, CEMVP-PD-P (Attn: Mr. Kip Runyon), 1222 Spruce St., St. Louis, MO 63103-2833.

FOR FURTHER INFORMATION CONTACT:

Kip Runyon, Environmental Planner, Regional Planning and Environmental Division North, at 314-331-8396 or by email at [e-mail].

SUPPLEMENTARY INFORMATION:

USACE is charged with obtaining and maintaining a navigation channel on the Middle Mississippi River (MMR) that is nine feet deep and 300 feet wide with additional width in bends as necessary (commonly called the Regulating Works Project). As authorized by Congress, the Regulating Works Project is obtained by construction of revetment, rock removal, and river training structures to maintain bank stability and ensure adequate, reliable navigation depth and width. The Regulating Works Project is maintained through dredging and any needed maintenance to constructed features. The long-term goal of the Regulating Works Project, as authorized by Congress, is to obtain and maintain a navigation channel at the authorized dimensions and to reduce federal expenditures by alleviating the amount of annual maintenance dredging through the construction of river training structures. The Selected Plan consists of continuing with construction of new river training structures and revetment for navigation purposes until such time as the costs of placing more structures, including costs for any mitigation, are no longer justified by the resultant reduction in repetitive dredging quantities and associated costs. The Selected Plan also involves continuing to dredge as necessary, completing known bankline stabilization work to reduce the risk of a channel cutoff, placing additional revetment, and continuing to maintain existing structures.

The remaining construction associated with the Selected Plan is currently estimated from programmatic analysis to require approximately 4.4 million tons (2.9 million cubic yards) of rock. Dredge quantities are expected to decrease from their current average annual quantity of approximately 4 million cubic yards to approximately 2.4 million cubic yards after construction of new river training structures and any compensatory mitigation is complete. These estimates are based on assumptions of Congressional funding levels, rock prices, dredging costs, sediment loads, mitigation costs, etc. Because these assumptions are uncertain, the estimated quantity of construction could differ from actual implementation.

Environmental impacts of the work associated with the Selected Plan will continue to be avoided and minimized to the extent practicable. Placement of river training structures is expected to increase the acreage of low-velocity habitat that is considered important habitat for many MMR fish species. However, placement of river training structures is also expected to reduce shallow to moderate-depth, moderate-to high-velocity habitat that is important for some MMR fish guilds. Analysis of the impacts of the Selected Plan to main channel border habitat suggests that future construction of river training structures will result in the consideration of compensatory mitigation measures. The specific impacts of each work area and any necessary compensatory mitigation measures will be covered in Tier II Site Specific Environmental Assessments, as appropriate.

The ROD, Final Supplement I, and supporting documentation are available at: http://www.mvs.usace.army.mil/​Missions/​Navigation/​SEIS/​Library.aspx.

Brian L. Johnson,

Chief, Environmental Compliance Branch, Regional Planning and Environmental Division North.