Purpose
A Preliminary Engineering Report (PER) will evaluate existing issues at the Leech Lake Dam site with alternatives developed to address issues.
Location
The Leech Lake Dam is located at the outlet of the reservoir on the Leech Lake River, 27 miles above the junction with the Mississippi River. The dam is at the northwest edge of the city of Federal Dam in Cass County, Minnesota. The Leech Lake Dam is on U.S. Army Corps of Engineers fee-owned land, although much of this is also tribal land since the Leech Lake River is the boundary of the Leech Lake Band of Ojibwe Reservation.
Description
Leech Lake Dam was constructed in the early 1880s under the Rivers and Harbors Act as a timber spillway with earth and timber embankment. The spillway was reconstructed with concrete piers and downstream apron was replaced with concrete. The cofferdam breached during construction of the concrete aprons in 1957, resulting in loss of fourteen spillway bays which were replaced with earth embankment. Since then, the major components of the dam have remained relatively the same.
The Corps’ periodic assessment program determined the dam safety risks are low, requiring no dam safety modifications. But there remains numerous operations and maintenance concerns related to the antiquated structure. Only five of 26 bays have operable gates, and the remainder are wooden stoplogs. The existing stoplog bays are difficult to operate and there is no reliable means to remove all the stoplogs for high flows. The operable gates have freezing issues in the winter. There are additional maintenance concerns with scour protection, adequacy of wingwalls at the abutments, unusable bulkheads or lack of secondary closure at the spillway bays, removal of floating bogs that clog the spillway bays, and concrete degradation.
Status
The project delivery team was assembled in spring of 2023 and held an initial kick-off meeting in April of 2023. A design charrette for the statement of work (SOW) was held in October 2023. Through the development of the SOW, the project delivery team identified the need for Hydraulic and Hydrologic Modeling in order to develop the SOW. This modeling will be completed by Corps staff in October 2024. The project delivery team will finalize the statement of work SOW and cost estimate, with anticipation of awarding a contact in in March 2025 to develop a PER.
Funding
The project received $1,498,725 in fiscal year 2023 funds for the development of the PER. To date, $277,359 has been expended on the development of the SOW for the PER.
There is a separate proposal for fish passage at Leech Lake. This rehabilitation work is mostly separable from the fish passage concept currently proposed.
Authority
Congress authorized the project as part of the River and Harbor Act approved July 3, 1930.
Funding
Estimated repair cost: $1,000,000