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2. United States Army Corps of Engineers (USACE)
3. Mississippi Valley Division
4. St. Paul District
5. Environmental Documents

Title:	Upper Mississippi River System Environmental Management Program Definite Project Report/Environmental Assessment (SP-24) : Pool 8 Islands Phase III Habitat Rehabilitation and Enhancement Project, Pool 8, Upper Mississippi River, Vernon County, Wisconsin and Houston County, Minnesota
Authors:	United States. Army. Corps of Engineers. St. Paul District.
Keywords:	Restoration ecology Environmental protection Environmental management Wetlands Mississippi River
Publisher:	United States. Army. Corps of Engineers. St. Paul District.
Abstract:	The Pool 8 Islands Phase III Habitat Rehabilitation and Enhancement Project is located in the lower portion of pool 8 of the Upper Mississippi River. The study investigated habitat conditions and concerns over a 3,000-acre area of the open, lake-like portion of lower pool 8. The habitat concerns within the study area center around the general degradation of habitat quality in lower pool 8. This degradation has been the result of the loss of islands, declining bathymetric diversity, and a decline in aquatic vegetation over the past few decades. Most of the study area lies within a closed portion of the Upper Mississippi River National Wildlife Refuge and is considered critical habitat for migrating waterfowl and other water birds. This decline in migration habitat quality is of great concern to the U.S. Fish and Wildlife Service and State resource management agencies. Due to its size, differing site conditions, and differing habitat goals and objectives, the study area was subdivided into five smaller areas for ease of planning. This allowed the planning of habitat restoration to be more efficient and to better meet the habitat needs within each of these areas. The planning process focused on the restoration of islands and river processes to restore habitat diversity within the study area. Because it is not possible to restore or create ideal habitat conditions for all forms of fish and wildlife, features were designed and evaluated primarily to improve conditions for migratory waterfowl. However, once the basic island layouts and designs were developed, they were modified to benefit other fish and wildlife wherever possible. For example, islands were positioned to maintain and/or encourage flowing channels for riverine fish or to provide protected deepwater habitat for overwintering Centrarchids. Features such as mudflats were incorporated into the island designs to provide habitat for shorebirds and wading birds. The focus in the 550-acre Three West area was on the restoration of migration habitat for dabbling ducks and the maintenance of flowing channel habitat. Eight island restoration alternatives were developed and evaluated for this area. The recommended plan is to construct six islands, with two mudflats incorporated into the island designs. The estimated construction cost of the plan for the Three West area is $5,185,000. Planning in the 470-acre Three North area also focused on the restoration of migration habitat for dabbling ducks. In additions, islands were designed to enhance flowing channels and to provide overwintering habitat for Centrarchids. Five island restoration alternatives were developed and evaluated for this area. The recommended plan is to construct four islands, with a mudflat incorporated into one island's design. In addition, four small seed islands are recommended in an area where river forces should then cause sediment deposition to form larger islands. The estimated cost of the plan for the Three North area is $3,420,000. The 1,600-acre Three Central has deeper water and is more open (no remnant islands) than the two previously discussed sub-areas. The focus in this area was on the restoration of migration habitat for diving ducks, along with enhancing flowing channels and providing oveIWintering habitat for Centrarchids. Eight island restoration alternatives were developed and evaluated for this area. The recommended plan is to construct seven islands, with a mudflat incorporated into one island's design. The estimated cost of the plan for the Three Central area is $6,100,000. The Three East area is located along the Wisconsin side of the floodplain, near Stoddard, Wisconsin. Planning in this area addressed concerns with maintaining the delta of Coon Creek, a mosaic of wetland habitats. The recommended plan is to construct three rock breakwaters to protect the delta from river currents and wind-induced wave action. This will protect the delta habitat and encourage the growth of the delta. The estimated cost of the plan for the Three East area is $645,000. The Three Northwest area is located along the Minnesota side of the floodplain, near Brownsville, Minnesota. Study in this area looked at the effects of sediment deposition from Wildcat Creek on wetland habitats. Two alternatives for rerouting the mouth of Wildcat Creek were evaluated. The conclusion is that sedimentation from Wildcat Creek in not having unacceptable adverse effects on the wetland habitats and therefore, no action is recommended at this time. Resource management agencies will continue to monitor the situation The overall recommended plan is to construct seventeen islands, four seed islands, and three breakwaters at an estimated cost of $15,714,000 (including sunk general design costs). The project will restore and/or create about 123 acres of islands, nearly doubling the amount of island acreage that was remaining in lower pool 8 in 1989. The addition of these islands would bring the total island acreage in lower pool 8 to over 300 acres, approximately the amount present in 1961. The islands recommended for construction will protect about 1,000 acres of aquatic habitat from large wind fetches, improving conditions for the growth of aquatic vegetation. This constitutes about 10 percent of the lake-like portion of lower pool 8. Substantial habitat benefits to shorebirds and wading birds are expected to accrue due to the creation of about 80,000 linear feet of sandy shoreline and four mudflats totaling about 22 acres. The sandy shorelines of the islands will also provide a substantial amount of area available for turtle nesting. The 123 acres of islands created will provide habitat for terrestrial and semiaquatic species of wildlife. This type of habitat is nearly non-existent in the areas where the islands would be constructed. The islands will help maintain about 20,000 linear feet of submerged channel, which will contribute to aquatic habitat diversity in this area, primarily for riverine fish species and mussels. Two protected deepwater areas about 60 and 40 acres in size, respectively, will be created that will provide overwintering habitat for Centrarchids and other backwater fish species. This type of habitat is of critical importance in the project area where overwintering habitat is almost non-existent. Project construction is scheduled to begin in 2005 and be completed in 2009. Construction of the Three West and Three North area islands would take place first, to be followed by construction of the Three Central area islands. Construction of the Three East area breakwaters would occur whenever it could be optimally fit into the construction schedule. The entire project lies within the Upper Mississippi River National Wildlife and Fish Refuge. Once completed, the project would be turned over to the U.S. Fish and Wildlife Service for operation and maintenance.
Description:	Definite Project Report with Integrated Environmental Assessment
Rights:	Approved for Public Release; Distribution is Unlimited
URI:	https://hdl.handle.net/11681/36775
Size:	205 pages / 28.6 MB
Types of Materials:	PDF/A
Appears in Collections:	Environmental Documents