Purpose
A Preliminary Engineering Report (PER) will evaluate existing issues at the Leech Lake Dam site and provide alternatives developed to address these 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 (USACE) 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 an earth and timber embankment. The spillway was reconstructed with concrete piers, and the 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 an earth embankment. Since then, the major components of the dam have remained relatively unchanged.
USACE’s periodic assessment program determined the Leech Lake Dam safety risks are low, requiring no dam safety modifications. However, numerous operations and maintenance concerns related to the antiquated structure remain. 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 a 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 2023 and held an initial kick-off meeting in April 2023. A design charrette for the Scope of Work was held in October 2023. The project delivery team has determined that the PER Scope of Work should be split into two phases. Phase 1 will focus on the gates and bays and will be conducted in-house by USACE staff. Phase 2 will be completed through an architect/engineer contract and will focus on structural elements such as the wing walls, apron and concrete. USACE staff are currently working on Phase 1 are expected to complete Phase 1 in June 2026 and award an architect/engineer contract for Phase 2 in October 2026.
Authority
Congress authorized the project as part of the River and Harbor Act approved July 3, 1930.
Funding
The project received $1,498,725 in fiscal year 2023 for the development of the PER. To date, $437,128 has been expended on the development of 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.