Please use this identifier to cite or link to this item:
Title: Upper Mississippi River System Environmental Management Program Definite Project Report and Integrated Environmental Assessment Project #114844 : Harpers Slough Habitat Rehabilitation and Enhancement Project, Pool 9, Upper Mississippi River, Allamakee County, Iowa and Crawford County, Wisconsin
Authors: United States. Army. Corps of Engineers. St. Paul District.
Keywords: Restoration ecology
Environmental protection
Environmental management
Mississippi River
Publisher: United States. Army. Corps of Engineers. St. Paul District.
Abstract: The Harpers Slough Habitat Rehabilitation and Enhancement Project is located on the Iowa side of the Upper Mississippi River in lower Pool 9, near Lynxville, Wisconsin. The proposed project is part of the Upper Mississippi River System Environmental Management Program. The site lies within the Upper Mississippi River National Wildlife and Fish Refuge. The overall recommended plan is to protect approximately 46 acres of existing islands and construct 52 acres of new islands at an estimated first cost of $17,427,000 (including sunk general design costs). The average annual equivalent of these costs equals $823,400. In addition to these costs, there will be additional annual O&M costs of $11,100 and annual monitoring costs of $38,200 for a total average annual project cost of $872,700. The project would protect, restore and/or create about 98 acres of islands and produce an estimated 618 average annual habitat units. Annual project cost per annual habitat unit amounts to $1,400. The habitat concerns within the study area center around the general degradation of habitat quality in lower Pool 9. This degradation is the result of the loss of islands, declining bathymetric diversity, and a decline in aquatic vegetation, mainly emergent vegetation, over the past few decades. However, submersed vegetation has rebounded in the last 20 years. The study area lies within the Upper Mississippi River National Wildlife and Fish Refuge and is considered critical habitat for migrating waterfowl and other water birds. The decline in migration habitat quality is of great concern to the U.S. Fish and Wildlife Service and State resource management agencies. The planning process focused on the protection and restoration of islands and river processes to restore habitat diversity within the approximately 3,500-acre study area. Because it is not possible to restore or create ideal habitat conditions for all forms of fish and wildlife, measures were designed and evaluated primarily to improve conditions for State and Federal natural resource agencies’ priority communities: migratory waterfowl and native fish species. However, once the basic island layouts and designs were developed, they were modified to benefit other fish and wildlife wherever possible. Islands were positioned to maintain and/or encourage flowing channels for riverine fish and/or to provide protected deepwater habitat for overwintering centrarchid fish such as bluegills, crappie, and largemouth bass. Measures such as emergent wetlands/mudflats were incorporated into the island designs to provide habitat for shorebirds and wading birds. To identify alternatives, measures were combined in various logical combinations and constraints were imposed to minimize impacts to native mussels. The resulting six identified alternatives (including the no-action alternative) were evaluated in detail for the Harpers Slough HREP. The U.S. Fish and Wildlife Service’s 1980 version of Habitat Evaluation Procedures was used to quantify and evaluate the potential project effects and benefits. In addition to the base project of protecting the existing island complex, two action alternatives were considered “Best Buy” in evaluation of cost effectiveness and incremental cost using the Institute of Water Resources economic analysis program called IWR-Plan. Based on the incremental analysis and other factors, Alternative 2, is recommended for implementation. Under Alternative 2, the acreage of emergent and rooted floating aquatic vegetation is expected to increase by over 50 percent and submersed aquatic vegetation is predicted to more than double when compared to the no action alternative, which is synonymous with the future without project conditions. Given the low rates of sediment deposition in this reach of the Upper Mississippi River, the project area will continue to be aquatic habitat throughout the 50-year life of the project, and the project features will continue to enhance this habitat. Project construction would likely be initiated in 2015 and be completed in 2018. 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 and Integrated Environmental Assessment
Rights: Approved for Public Release; Distribution is Unlimited
Size: 165 pages / 7.69 MB
Types of Materials: PDF/A
Appears in Collections:Environmental Documents

Files in This Item:
File Description SizeFormat 
HarperSloughDPR.pdf7.69 MBAdobe PDFThumbnail