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

Title:	Feasibility Report and Environmental Assessment : Marsh Lake Ecosystem Restoration Project, Minnesota River, Big Stone, Lac qui Parle, and Swift Counties, Minnesota
Authors:	United States. Army. Corps of Engineers. St. Paul District. Minnesota. Department of Natural Resources.
Keywords:	Marsh Lake (Big Stone County-Swift County; Minn.) Restoration ecology Environmental protection Environmental management
Publisher:	United States. Army. Corps of Engineers. St. Paul District.
Abstract:	The purpose of this Feasibility Report and Environmental Assessment is to document the planning process for ecosystem restoration of the Marsh Lake area on the Minnesota River, to provide opportunity for participation in the planning process for river management partners and the public, to meet Corps of Engineers planning guidance and to meet National Environmental Policy Act (NEPA) requirements. The purpose of this project is to restore the aquatic and riparian ecosystems in the Marsh Lake project area. Impoundment of Lac qui Parle and Marsh Lake, diversion of the Pomme de Terre River into Lac qui Parle, and river regulation have significantly altered the ecosystem state. Aquatic ecosystem restoration is a primary mission of the Corps’ Civil Works program, and is defined as achieving a “return of natural areas or ecosystems to a close approximation of their conditions prior to disturbance, or to less degraded, more natural conditions“(EP 1165-2-502.) In some circumstances, as at Marsh Lake, a return to pre-disturbance conditions may not be feasible. In those instances, “the goal is to partially or fully reestablish the attributes of a naturally functioning and self regulating system.” The goal of this project is to return the Marsh Lake area ecosystem to less degraded, more natural conditions by restoring natural functions and processes. The original construction of the Marsh Lake Dam was intended to serve as a flood damage reduction measure as well as a recreational feature to the region, primarily through the creation of a static pool on the river. The intended flood damage reduction benefits provided by the Marsh Lake Dam are minor due to effectiveness of the Lac qui Parle Dam downstream. Marsh Lake is a popular recreation destination in the region as shown by visitor numbers. As with many projects constructed at the time, a full understanding of the ecology of the system was not of primary concern. Since impoundment, Marsh Lake has undergone significant degradation of aquatic habitat due to a number of stressors including high sediment and nutrient loading, a fixed crest dam that prevents low seasonal water levels, high turbidity from wind-driven sediment resuspension, and abundant common carp that increase turbidity and graze off submersed aquatic vegetation and macroinvertebrates. Although Marsh Lake provides an open water area for migratory waterfowl to rest and islands for nesting colonial waterbirds, degradation of the aquatic ecosystem there limits habitat suitability for many species of fish and wildlife. The underlying purpose and need for this project is to restore the degraded Marsh Lake ecosystem. The stated goal of Marsh Lake Ecosystem Restoration Project is to “return the Marsh Lake area ecosystem to a less degraded and more natural condition by restoring ecosystem structure and functions.” The intent of the Marsh Lake ecosystem restoration project is to increase variability in ecosystem processes, restore a more natural water level regime, aquatic habitat connectivity, and a vegetated lake ecosystem state.
Description:	Feasibility Report and Environmental Assessment
Rights:	Approved for Public Release; Distribution is Unlimited
URI:	https://hdl.handle.net/11681/36933
Size:	234 pages / 8.99 MB
Types of Materials:	PDF/A
Appears in Collections:	Environmental Documents