Leech Lake Dam Preliminary Engineering Report (PER)

U.S. Army Corps of Engineers, St. Paul District
Published April 24, 2024
Updated: April 24, 2024


A Preliminary Engineering Report (PER) will evaluate existing issues at the Leech Lake Dam site with alternatives developed to address issues. 


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.


Leech Lake Dam was originally constructed in the early 1880s under the Rivers and Harbors Act as a timber spillway with an earth and timber embankment. Over the history of the dam, 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 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, so no dam safety modifications are justified. 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.


The project delivery team was assembled in spring of 2023 and held an initial kick-off meeting in April of 2023. The project delivery team is developing a statement of work (SOW) and cost estimate, with anticipation of awarding a contact in October 2024 to develop a PER. 


The project received $1,498,725 in fiscal year 2023 funds for the development of the PER. To date, $207,747 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.


Congress authorized the project as part of the River and Harbor Act approved July 3, 1930.


Estimated repair cost: $1,000,000