Walla Walla District, U.S. Army Corps of Engineers

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US Army Corps of Engineers

Walla Walla District Website

A step towards navigable waters: A history of McNary Lock and Dam

Today, McNary is an essential part of the river highway that was envisioned before the formation of the Walla Walla District. It sits as the midpoint, the last lock on the Columbia before the mouth of the Snake River. With its 14 generator units, McNary is also an incredible source of hydropower, capable of producing 980-megawatts or enough electricity to power about 686,000 homes.

Lucky Peak Dam became the first dam to be designed and constructed by the new Walla Walla District. Since its construction, Lucky Peak is estimated to have prevented over a billion dollars of flood damage.

Guarding the Treasure Valley: A history of Lucky Peak Dam

Every year, snowmelt from the surrounding mountains flows into creeks and streams that join the Boise River. When flows reach 7,000 cubic feet per second or higher, the river is considered at flood stage.

The Mill Creek Project is over 80 years old, older than the Walla Walla District, which will be celebrating its 75th Anniversary on Nov. 1, 2023. Since construction was completed in 1942, at least $300 million in potential flood damages have been prevented by the Mill Creek Project’s combined storage and channel operations.

Through fair or foul weather: A history of the Mill Creek Project

In 1931, a torrent of brown water roared down Mill Creek, with water levels rising at a rate of one foot per hour. The water escaped the confines of the riverbanks and rushed through the City of Walla Walla, destroying homes, roads and bridges. Born in the wake of this disastrous event, the Mill Creek Project now stands to protect the city from floods like this.

NWW PRT members at the Generator Staging Base (GSB) in Ponce.

Keeping the lights on: Walla Walla Temporary Power Team installs generators in the wake of Hurricane Fiona

On September 19, the day after Hurricane Fiona made landfall near Punta Tocón, members of the U.S. Army Corps of Engineers, Walla Walla District Planning and Response Team (PRT) boarded a plane in Atlanta and flew to Puerto Rico. The team landed in San Juan at 8 p.m., on a mission to install generators and provide temporary emergency power to the island.

Welcome to the Walla Walla District!

The Walla Walla District constructs, operates, maintains, and secures multipurpose infrastructure to energize the economy, reduce flood risk, and serve as stewards of water resources for the Snake River Basin and the Nation.

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