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UMRR Program - Pool 12 Overwintering HREP

Published March 8, 2019

Regional Program Manager
(309) 794-5428

Pool 12, Upper Mississippi River Mile 564.0 - 573.0, Jo Daviess County, Illinois

The Pool 12 Overwintering project area is in Jo Daviess County, Illinois, upstream of Bellevue, Iowa. The project lies generally between the Mississippi River's main channel and the railroad tracks that parallel the river's east bank. The project lands are federally owned.

The project area is comprised primarily of a series of islands, backwater channels, and backwater lakes that are part of the Upper Mississippi River National Wildlife and Fish Refuge.

The goals of the project are to restore and protect off-channel aquatic habitat and restore floodplain forest habitat. The objectives identified to meet these goals are (1) Increase the amount of deep water habitat in the backwater lakes complex of Pool 1,2 as measured by acres, to provide pool-wide overwintering fish habitat; (2) Increase depth diversity in backwater lakes complex of Pool 12, as measured by acres, to provide year round fish habitat; (3) Increase sustainability of aquatic habitat in the backwater lakes complex of Pool 12, as measured by acres, by decreasing the sedimentation in the complex; and (4) Increase areal coverage in acres of forest stands with hard mast-producing trees as a dominant or component species in floodplain forest areas surrounding the backwater lakes of Pool 12.

Project Features:
· Excavate channels in backwater areas
· Construct land and aquatic deflections berms
· Plant hard mast trees on land berms
· Construct rock closure structures

The Recommend Plan would restore backwater habitat at four lakes (Sunfish Lake, Stone Lake, Kehough Slough, and Tippy Lake) by excavating approximately 63 acres of deep backwater channels to a depth of 8 feet below flat pool providing overwintering and year-around habitat for fish in the surrounding 6,942 acres.  The recommend plan would also establish mast-producing tree on approximately 40 acres of land berms.

Following lock and dam construction, river sediments have continued to accumulate in backwater areas of Pool 12.  This sedimentation has reduced the depth and area of historic backwater sites used by fisheries resources for various life-stage needs. Including overwinter survival.  It also has blocked entrances to backwater fishery overwintering areas, which reduces the overall value of otherwise useable fish habitat. Presently, overwintering habitat for fish and backwater habitat for both waterfowl and fish are very limited in Pool 12. Sedimentation of backwater lakes and sloughs has reduced the value of historic overwintering areas. The Iowa Department of Natural Resources has documented that the overwintering habitat in Pool 12 has become a limiting factor for survival of riverine fish.

The final Definite Project Report (now referred to as a Feasibility Report) was approved for all four areas of construction. The construction contract for Stage I (Sunfish Lake) was awarded in August 2013. Construction of Stage I (Sunfish Lake) was completed in May 2016. The construction contract for Stage II (Stone and Tippy Lakes) was awarded in July 2015. It is scheduled to be completed by October 2019. Stage III (Kehough Slough) was awarded in August 2016 and is scheduled to be completed by October 2019.

CG - Construction General

Summarized Project Costs

Estimated Federal Cost   $20,870,000
Estimated Non-Federal Cost N/A 
Estimated Total Project Cost $20,870,000
Allocations Prior to FY 2019 $15,908,000
FY 2018 Allocation $220,000
FY 2018 Total Capability $220,000


Major Work Item Current Year
FY 2019:
Funds are being used to continue Stage II construction of Stone Lake and Tippy Lake and Stage III Kehough Slough construction, and to update the interim operations and maintenance manual for Pool 12 Overwintering HREP project. During construction and post-project monitoring will be applied using active adaptive management principal to inform the placement and design of future HREPs.