The U.S. Army Corps of Engineers, Rock Island District (District), requests your review of the Integrated Feasibility Report and Environmental Assessment titled, Green Island Habitat Rehabilitation and Enhancement Project, dated September 20, 2023. The Rock Island District is interested in your review and comments regarding the alternative analysis and project outcomes. The District is also letting the public know how the District plans to meet its environmental compliance requirements. The plan can be found at the following link: https://www.mvr.usace.army.mil/Missions/Environmental-Stewardship/Upper-Mississippi-River-Restoration/Habitat-Restoration/Rock-Island-District/Green-Island/
The public is invited to submit comments regarding the alternative analysis and proposed alternative for this project through October 21, 2023.
Comments can be submitted through email at: PublicInvolvement@usace.army.mil, or by writing to the address below.
To request a paper copy or CD, contact the District’s Environmental Compliance Branch at 309-794-6104, email PublicInvolvement@usace.army.mil, or write to:
Department of the Army
US Army Corps of Engineers, Rock Island District
Attn: Bales (PD-P)
Clock Tower Building
P. O. Box 2004
Rock Island, IL 61204-2004
Project Information
Green Island Project (Project) is located near Green Island, Iowa. The Project lies within the Green Island Wildlife Management Area (WMA) which is managed by Iowa Department of Natural Resources. The Green Island WMA is located in Pool 13 of the Upper Mississippi River (UMR) below the confluence of the Maquoketa River.
The Project area is a 4,000-acre wetland complex that includes shallow lakes, emergent vegetation and managed moist soil areas, and braided channels surrounded by degrading riparian timber.
The goals are to maintain, enhance and restore quality habitat for all native and desirable plant, animal and fish species and maintain, enhance, restore and emulate a natural river process, structures and function for sustainable ecosystem. The objectives identified to these goals are (1) Restore the historic hydraulic cycle considering current infrastructure; (2) Improve sediment management across the Green Island study area, reduce sedimentation impacts on existing habitat, and reduce the loss of water storage capacity due to sedimentation; (3) Restore Green Island aquatic ecosystems for fish and other aquatic organisms by increasing the quality and quantity of aquatic habitat available; (4) Restore the quality, and diversity of vegetation within the Green Island study area, including emergent, submerged aquatic, and forest vegetation; and (5) Restore bathymetric and topographic diversity within the Green Island study area.
Habitat and cost benefits were estimated by the PDT for each measure. Habitat benefits were estimated using Habitat Evaluation Procedures. Cost effective & incremental cost analyses were conducted by the PDT to identify cost-effective plans and reveal changes in cost for increasing levels of environmental output.
Proposed Alternative
Alternative 6 Balance Water Level Management - this will restore quality habitat in the project area. This plan includes constructing a pump station with two multidirectional pumps that can pump water into and out of the area, allowing for a more natural hydrologic cycle. In addition to constructing a pump station, several existing water control structures will be replaced to further increase the ability to manipulate water within the project area. Several areas will be dredged to restore overwintering habitat for fish and other aquatic species. The dredged material will be used to increase the topographic diversity of the area. Dredging will improve connectivity to water bodies within the project area and berms to help break up wind-driven waves. This will allow water and wildlife to move more freely through the area. A ridge and swale area will be constructed to increase topographic diversity for native plants and animals. Timber stand improvement techniques such as tree thinning, tree and shrub planting, and invasive species treatments will be implemented to restore the wetland forest habitat. Lastly, an in-channel sediment trap will be created to capture and control the sediment coming into Green Island.