The U.S. Army Corps of Engineers, Rock Island District (District), requests your review of the Environmental Assessment (EA) titled Channel Maintenance Dredging, Duck Creek Cut, Mississippi, Pool 13, River Mile 554.3, and Deadman’s Light Cut, Mississippi River, Pool 12, River Mile 568.5 and public notice for the proposed discharge of dredged material as required by Section 404 of the Clean Water Act.
The purpose of this channel maintenance dredging project is to restore the navigation channel back to standard operating standards. Restoring the channel would allow commercial navigation to continue with a reliable and safe navigation channel depth and width. The public is invited to submit comments regarding the alternative analysis and preferred alternative for this project through September 30, 2021.
Comments can be submitted via this online COMMENT FORM, through email at: PublicInvolvement@usace.army.mil, or by writing to the address below.
To request a paper copy or CD, contact the Rock Island District at 309-794-4200, email: PublicInvolvement@usace.army.mil, or write to:
Department of the Army
US Army Corps of Engineers, Rock Island District
Attn: Davi Michl (PD-P) Clock Tower Building
P. O. Box 2004
Rock Island IL 61204-2004
PROJECT INFORMATION
In order to maintain the 9-foot navigation channel, dredging needs to be performed at various locations on the Upper Mississippi River within the U.S. Army Corps of Engineers, Rock Island District (District). There is currently a need to dredge the navigation channel between river mile 554.1-555.0, referred to as Duck Creek, and between river mile 568.5-568.8, Deadman’s Light. Dredged material is removed from the channel by hydraulic or mechanical dredging. The District has not dredged Duck Creek since 1962 with placement on the left descending bank line between RM 554.3-554.7 and the right descending bank line between RM 554.3- 555.4. Deadman’s Light Cut has not been dredged since 1969 with placement on the right descending bank line between RM 568.5 – 568.9. Surveys estimate approximately 15,000 CY at the Duck Creek cut, and approximately 39,000 cubic yards (CY) at the Deadman’s Light cut needing to be dredged. Dredging quantities will likely change due to river conditions. The On Site Inspection Team (OSIT) and the District met on site in both reaches to evaluate potential placement options for natural resources impacts for the pending dredging event in both reaches.
ALTERNATIVES CONSIDERED
- No Action
- Dredge and place material on bank line of Site 1, Duck Creek, RM 554.3 (OSIT preferred placement site).
- Dredge and place material on bank line at Site 6 Deadman’s Slough, RM 567 (OSIT preferred placement site).
- Dredge and place material on bank line at site Site 7, Deadman’s Light, RM 569.
PREFERRED ALTERNATIVE
The District determined Alternative 2 (Site 1) is the preferred alternative for the Duck Creek Reach in Pool 13 and Alternative 3 (Site 6) is the preferred alternative for the Deadman’s Light Reach in Pool 12. Site 1 and Site 6 were selected by the District based on its low potential for environmental impacts. Dredged material would be placed up to but not exceeding the OHWM of 588.32 ft NAVD88 for Site #1, and 593.31 ft NAVD88 for Site #6. Dredged material on the bank line (to an elevation of 588.32 ft NAVD88 for Site #1, and 593.31 ft NAVD88 for Site #6) has no impact on flow velocity and provides a stable location for the dredged material. Placement of dredged material at these sites would present no-rise in the water surface elevations at this site or upstream of this site. This alternative also provides the ability for the District to use the sites in the future if the need arises and there is capacity available.