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US Army Corps of Engineers St. Paul District Mississippi Valley Division
Feasibility Report and Environmental Assessment
Marsh Lake Ecosystem Restoration Project
Big Stone, Lac qui Parle, and Swift Counties, Minnesota
Photo by Ron Bolduan
Completed in conjunction with the Minnesota Department of Natural Resources
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Summary Introduction This report was prepared in response to the study authorization contained in a
Resolution of the Committee on Public Works of the U.S. House of Representatives,
May 10, 1962. The resolution reads as follows:
Resolved by the Committee on Public Works of the House of Representatives, United
States, that the Board of Engineers for Rivers and Harbors be, and is hereby, requested
to review the report of the Chief of Engineers on the Minnesota River, Minnesota,
published as House Document 230, 74th Congress, First Session and other pertinent
reports, with a view to determining the advisability of further improvements in the
Minnesota River Basin for navigation, flood control, recreation, low flow augmentation,
and other related water and land resources.
In response to the study authority the reconnaissance phase of the study was
completed in December 2004 (USACE 2004) and approved in January 2005. The
reconnaissance study resulted in the finding of Federal interest in and potential solutions
to several existing water resources problems that warrant feasibility studies, including
ecosystem restoration at Marsh Lake.
The Minnesota Department of Natural Resources (DNR) as the non-Federal
sponsor, and the U.S. Army Corps of Engineers, St. Paul District (Corps) initiated the
feasibility phase of the study on February 2, 2006. The feasibility phase study cost was
shared equally between the Corps and the sponsor.
This summary is intended to describe the major factors which were considered in
the investigation and influenced the decisions and recommendations documented in this
Planning Process and NEPA Starting in November 2000 through 2002, the DNR conducted a planning
process with interagency coordination and public participation to identify ways to restore
the Marsh Lake ecosystem.
In collaboration with the DNR and making use of the information generated from
the DNR's earlier planning for Marsh Lake, we identified the problems and opportunities,
set project objectives, identified and evaluated a number of alternative measures for
Marsh Lake ecosystem restoration, formulated alternative plans, assessed the costs,
benefits, environmental and social impacts of the alternative plans, coordinated with
agencies and the public, recommended a plan and documented this planning process in
this draft integrated Feasibility Report and Environmental Assessment (FR/EA).
This FR/EA has been prepared to meet Corps of Engineers planning guidance
and National Environmental Policy Act (NEPA) requirements. Following agency and
public review, a final FR/EA will be prepared. The St. Paul District Commander will
consider signing a Finding of No Significant Impact for the Marsh Lake Ecosystem
Restoration Project to conclude the National Environmental Policy Act (NEPA) process.
This planning process has been subject to Value Engineering Review, Agency
Technical Review; review by interested agencies and the public, and review by the
Corps of Engineers Mississippi Valley Division and by Corps Headquarters.
Major Conclusions and Findings Planning Objectives The investigation of the problems and opportunities led to the establishment of
the following planning goals and objectives for ecosystem restoration in the Marsh Lake
Goal: A return of the Marsh Lake area ecosystem to a less degraded and more natural
and functional condition
1. Reduced sediment loading to Marsh Lake over the 50-year period of analysis
2. Restored natural fluctuations to the hydrologic regime of Marsh Lake over the 50-year
period of analysis
3. Restored geomorphic and floodplain processes to the Pomme de Terre River over the
50-year period of analysis
4. Reduced sediment resuspension within Marsh Lake over the 50-year period of
5. Increased extent, diversity and abundance of emergent and submersed aquatic plants
within Marsh Lake over the 50-year period of analysis
6. Increased availability of waterfowl habitat within Marsh Lake over the 50-year period
7. Restored aquatic habitat connectivity between Marsh Lake, the Pomme de Terre
River and Lac Qui Parle over the 50-year period of analysis
8. Reduced abundance of aquatic invasive fish species within Marsh Lake over the 50-
year period of analysis
9. Increased diversity and abundance of native fish within Marsh Lake and the Pomme
de Terre River over the 50-year period of analysis
Alternatives A wide range of alternative measures were identified to address the planning
objectives. Alternative plans were formulated. Alternative measures evaluated as a part
of this study are as follows:
Modifications to the Marsh Lake Dam to enable passive and active water level
Provide for fish passage between Lac qui Parle Lake and Marsh Lake and the
Pomme de Terre River. Restore the Pomme de Terre River to its former channel
near its confluence with the Minnesota River. Construct a bridge over the
Pomme de Terre River to maintain access to the Marsh Lake Dam.
Construct rock wave-break islands in Marsh Lake to reduce wind fetch, wave
action, and sediment resuspension to restore aquatic vegetation.
Reconnect the abandoned fish rearing pond next to the Marsh Lake Dam with
the upper end of Lac qui Parle.
Install gated culverts in the Louisburg Grade Road to enable water level
management in upper Marsh Lake.
Modify the Reservoir Regulation Plan for the Lac qui Parle Flood Control Project
to include growing season drawdowns of Marsh Lake as needed to restore
aquatic vegetation in years when river discharge allows.
Construct recreational and educational features including a trail bridge over
Marsh Lake Dam to connect with the Minnesota State Trail, fishing access on
Marsh Lake, canoe access on the Pomme de Terre River, and an improved
recreation area at Marsh Lake Dam.
Monitor the ecological effectiveness of the Marsh Lake ecosystem restoration
features to provide information for future adaptive ecosystem management.
Local Support The non-Federal sponsor, the Minnesota Department of Natural Resources, has
expressed the desire for implementing ecosystem restoration and sponsoring project
construction in accordance with the items of local cooperation that are set forth in this
report. The financial analysis indicates that the non-Federal sponsor is financially
capable of participating in the project.
The Recommended Plan recommended for implementation is Alternative Plan 4
which consists of the following:
Restore the Pomme de Terre River to its historic channel
Breach dike at abandoned fish pond
Construct drawdown structure
Construct Louisburg Grade Road gated culverts
Modify the Marsh Lake Dam, construct fishway
Through the planning process outlined in this report, it was determined that Alternative
Plan 4, consisting of the measures noted above, provided the greatest increase in
benefits, addressing each planning objective, at the least cost. The Recommended Plan
will provide an increase of approximately 8400 Habitat Units at an average annual cost
of $474,000. In addition, a number of recreation features will be constructed (highlighted
in Section 7.2) that will provide approximately $225,000 of economic benefit at an 8.6
benefit-cost ratio with an average annual cost of $26,000. The total project costs of the
ecosystem and recreation features equals $9,967,000 with an annualized cost of
$500,000. The costs and benefits of the Recommended Plan are summarized below:
8400225,000$ Total Annual Benefits (Recreation)
Breakout of Total Project Costs and BenefitsMarsh Lake Ecosystem Restoration - Recommended Plan
Total Project First CostsInterest During Construction (4.125%)Present Worth of Investment
Annualized Total Project CostsAnnual Operations and Maintenance Costs
Total Annual Benefits (Habitat Units)
Rounded to nearest $1000
Ecosystem Restoration Features of the Recommended Plan
Recreation Features of the Recommended Plan
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