Legacy Foundations
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Shimmick has a long history of completing complex water projects, ranging from the world’s largest wastewater recycling and purification system in California to the record-setting Hoover Dam. In January 2021, we began operating as an independent company under new private ownership, at which time we began a transformation to re-envision our strategy to meet the nation’s growing need for water and other critical infrastructure.

Shimmick completes work at the world’s largest wastewater purification system in California, delivering Orange County’s Groundwater Replenishment System Expansion.

Shimmick secures new contract at the Antioch Desalination Plant to add a new reverse osmosis (RO) treatment train. This work will enable the plant to continue to provide a drought-resistant water supply, reduce reliance on imported water, enhance water reliability, support agricultural needs, and contribute to the overall water security and sustainability of the region San Joaquin Delta System and surrounding areas.

Shimmick is named the nation’s largest Dam and Reservoir builder and third largest builder of Water Supply by Engineering News Record for the first time in company history.

As an independent company under new ownership, Shimmick began a transformation to re-envision its strategy to meet the nation’s growing need for water and other critical infrastructure.
The new Shimmick entity, comprised of legacy companies Morrison Knudsen, Washington Group Companies, and legacy Shimmick, among others, is ranked the third largest dam contractor in the U.S. by Engineering News Record. Shimmick is ranked among the top 20 contractors in transportation, highways, bridges, mass transit and rail, water supply and water treatment.

Shimmick wins first build-finance project, the $260 million Gilcrease Expressway project, in Tulsa, Oklahoma.

Shimmick opens the Gerald Desmond Bridge, the first cable-stayed vehicular bridge in California.
Steve Richards, who started his career with Morrison Knudsen and served in various leadership positions within legacy companies Washington Group, is appointed President of AECOM’s civil construction division (now Shimmick).
AECOM purchases Shimmick and merges it with the existing Civil Construction & Mining group, doubling the size of the civil construction division.

Shimmick company Rust Constructors continues work at Black Thunder Mine to build infrastructure for the largest open pit coal mine in North America. Our work at Black Thunder dates back to 1993, when Washington Group International acquired Fuller Construction.

URS is acquired by AECOM for $5.3 billion and creates a Construction Services Division, within which the Civil Construction & Mining group now operates.
Shimmick expands geographic footprint to Washington State constructing water, electrical and large light rail projects in the Seattle metro area.

Shimmick starts a foundation group to perform work throughout the western United States and Hawaii. This work includes some of the most technical and challenging large diameter drilled shaft foundation projects in the U.S.

Shimmick wins a $140 million contract to construction the San Vicente Dam Raise, the tallest dam raise in the U.S. Shimmick continues to win additional major projects, including the $897M BART Extension to San Jose.

Washington Group is acquired by URS for $2.6 billion.
Shimmick legacy company Washington Group wins the contract to build the Olmsted Dam, the largest civil works project by the USACE.

Legacy Shimmick company Washington Construction Company acquires Raytheon Engineers and Constructors, changes name to Washington Group International.
In addition to highway and transit projects, Shimmick enters the water resources market, building dams, water and wastewater treatment plants throughout California.

Washington Construction Co. acquires Morrison Knudsen, a designer and contractor of major infrastructure throughout the world and one of the consortium of firms that built Hoover Dam, San Francisco–Oakland Bay Bridge, the NASA Vehicle Assembly Building, the Trans-Alaska Pipeline, and many other large projects of American infrastructure.


Shimmick, operating at the time as 21st Century Rail, wins the contract to design, build, operate and maintain the Hudson-Bergen Light Rail Extension in Jersey City, the nation’s first DBOM project.

Washington Companies merges with Kasler Corporation, a civil construction company operating primarily in Southern California.

Shimmick is founded in California.

Shimmick legacy company is established by Denny Washington as the Washington Construction Company in Missoula, Montana. Over the next three decades, the company expands throughout the region.
Shimmick legacy company Morrison Knudsen builds the Hoover Dam.