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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-13) : Long Lake Habitat Rehabilitation and Enhancement Project, Pool 7, Upper Mississippi River, Trempealeau and La Crosse Counties, Wisconsin
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 Long Lake project area is a 15-acre backwater lake situated among several other backwater channels and lakes in the same vicinity. Long Lake is located in pool 7 on the Wisconsin side of the main channel of the Mississippi River immediately downstream of lock and dam 6, This backwater area provides above average habitat for fish of the families centrarchidae, perchidae, and ictaluridae except for one limiting factor, periods of severe dissolved oxygen depletion in the late summer and winter months. The plan formulation process considered several alternatives that could improve dissolved oxygen to the lake. This assessment process primarily revolved around investigating sources of water having adequate dissolved oxygen that could be diverted into Long Lake, Most water bodies adjacent to Long Lake either proved to be an unreliable source of dissolved oxygen or there was the potential that other areas would be adversely affected by the diversion of this water. Only two viable alternatives remained following the original evaluation of options. These were two routes that would bring water in from the Mississippi River. The costs of the two alignments were essentially the same, Therefore, the recommended alignment was selected on the basis of habitat gains and avoidance of the need to acquire. The selected plan calls for excavation of a channel approximately 620 feet in length between the Mississippi River and Long Lake. It is estimated that 10,200 cubic yards of material would be removed to create the channel. A 48-inch-diameter reinforced concrete pipe with sluice gate would be placed along the channel to control inflow into the lake during periods of high flow. By introducing direct flow into Long Lake, minimum dissolved oxygen levels of 5 mg/l would be provided on a year-round basis to a majority of the lake area, Habitat unit gains have been projected to increase by over 800 percent in Long Lake from the with-out to the with-project condition. Improvement of the dissolved oxygen should lead to increased use of the area by fish throughout the year. Total direct construction costs of the selected plan are $139,900. Indirect costs for engineering and design work and construction supervision and administration bring the cost to $212,700. During the general design phase of this project, $50,000 was expended. Average annual operation and maintenance costs of the project are estimated to be $4,000 and would be the responsibility of the U.S. Fish and Wildlife Service, in cooperation with the non-Federal sponsor, the Wisconsin Department of Natural Resources.
Description:	Definite Project Report with Integrated Environmental Assessment
Rights:	Approved for Public Release; Distribution is Unlimited
URI:	https://hdl.handle.net/11681/36879
Size:	121 pages / 3.3 MB
Types of Materials:	PDF/A
Appears in Collections:	Environmental Documents