UMRR Program – Lower Pool 13 – Phase II HREP

USACE Rock Island District
Published Aug. 30, 2024
Mississippi River - Lower Pool 13

Mississippi River - Lower Pool 13

Location

Pool 13, Upper Mississippi River Miles 522.5 to 529.0, Carroll & Whiteside Counties, Illinois and Clinton County, Iowa.

Description

The Lower Pool 13 Habitat Restoration and Enhancement Project – Phase II, part of the Upper Mississippi River Restoration program, is located approximately three miles upstream of the city of Clinton, Iowa. The project features would be located entirely on federally owned land that forms part of the Upper Mississippi River National Wildlife and Fish Refuge. The area consists of backwater lakes, sloughs, flowing channels, and impounded water residing over historically flooded islands and remnant islands. The lower section of Pool 13 is located in a valley that is 1.5 to 4.5 miles wide and contains few land masses.

The goals are to maintain, enhance, restore, and emulate natural river processes, structures, and functions to promote a sustainable ecosystem; and to maintain, enhance, and create quality habitat for all native and desirable plant, animal, and fish species. The objectives identified to meet these goals are (1) enhance altered hydraulic connectivity; (2) improve water clarity, nutrient loading levels, and sediment loading/resuspension levels; (3) restore sediment transport regime for geomorphic pattern regulation, channel and floodplain features, and floodplain topography diversity; (4) restore habitat connectivity, riparian habitat, aquatic off-channel areas, terrestrial floodplain areas, and channel areas; and (5) enhance the diversity and population of native aquatic vegetation communities (Submerged Aquatic Vegetation, Emergent Aquatic Vegetation, Rooted and Floating), native floodplain forest and prairie communities, native fishes communities, native mussel communities, native bird communities, and amphibian and reptile communities.

Potential project features include the following:

  • Island restoration and stabilization
  • Backwater dredging
  • Water Level Management (Pool Drawdowns)
  • River structures (chevrons, rock mounds)

Background

Pre-impoundment, Pool 13 consisted of permanent and seasonal lakes, forested wetlands, bottomland forests, braided islands, wet meadows, and main channels and sloughs. Lock and Dam 13 began operation in the late 1930s; the implementation resulted in the inundation of several thousand acres of floodplain in lower Pool 13. Connectivity of backwater and off channel areas within the Project area changed from seasonal discharge related events to year-round connectivity. The resulting constant inundation has contributed to island/landmass erosion, sedimentation, and resuspension of sediments due to wave action.

Forecasted future conditions anticipate continued backwater sedimentation of fine materials. Wave resuspension of sediments in the Project area will continue to affect the sustainability of aquatic vegetation due to influences of the Elk River, ambient turbidity levels, and wind fetch. Fisheries resources in the Project area are expected to continue to degrade due to a lack of structure, habitat diversity, and overwintering habitat. Migratory water bird habitat will continue to be variable, primarily dependent on the stability levels of year-to-year aquatic plant production. A variety of physical, chemical, and biological stressors individually and cumulatively affect the quantity and quality of habitat for biota in the Project area.

Status

The feasibility report was initiated in 2022. The report is scheduled for completion in 2026.

Additional Information

Authority

Water Resource Development Act (WRDA) of 1986 under Section 1103 (33 U.S.C 2201 et seq.; P.L. 99-662, 1986) 

CG - Construction General

Summarized Project Costs

Estimated Federal Cost

$20,000,000

Estimated Non-Federal Cost

$0

Estimated Total Project Cost

$20,000,000

Allocations Prior to FY 2024

$381,586

FY 2024 Allocation

$600,000

FY 2025 President’s Budget

$600,000

FY 2025 Total Capability

$600,000

 

Major Work Item Current Year

FY 2024: The Project moved forward with the feasibility report and pre-project monitoring.

Major Work Item Next Fiscal Year

FY 2025: If funded, the feasibility report and pre-project monitoring will continue.