Water & Wastewater

Project Description: IMCO is constructing a new headworks facility in partnership with Keller. The facility will include new influent pumping, screening, grit removal, and associated infrastructure. The Nampa WWTP Project Group G New Headworks project will also finalize site-wide...

IMCO is constructing a new eight million gallon prestressed and partially buried concrete tank to store the City of Everett’s drinking water. The current tank is susceptible to seismic damage and this new structure will provide an upgraded system...

IMCO Construction and designer Carollo are partnering to replace sewer utilities for the City of Tacoma, performing preconstruction services, evaluating options to determine the best alignment for new large-diameter pipe and a strategy for the re-use of existing pipeline...

This project provides improvements to the existing lift station and force main pipes to provide adequate pumping capacity to facilitate future sewage conveyance at the Roeder Lift Station. The improvements consist of construction of a new sanitary sewer lift...

The City of Everett owns and operates a water filter plant and regional water distribution system that serves more than 675,000 customers daily. The water filter plant was originally constructed in 1983 and now has aging infrastructure elements in...

Upon the successful completion of a new water treatment facility, IMCO Construction was hired to manage and operate the new facility for Rio Tinto. Holden Mine is a remote location near Holden Village, accessible by ferry, followed by a...

The Boise Project Board of Control (BPBC) awarded the New York Canal Lining project to IMCO in May 2024. IMCO replaced one linear mile of canal lining in downtown Boise’s New York Canal to enhance the canal’s integrity, improve...

IMCO teamed with Stantec on this design-build project to convey water from the Snake River up to a new water treatment plant at the Mountain Home Air Force Base. An intake in the Snake River with three vertical turbine...

On January 18, 2023, the City of Lewiston’s 100-year-old potable water reservoir ruptured. The escaping water caused considerable damage to the earthen berm, sloped concrete liner, and cover structure. The City reached out to IMCO and Stantec to design and perform...

IMCO Construction was contracted hired by General Contractor Hensel Phelps to perform the earthwork, water and wastewater utilities, and pond liners for a client’s datacenter in Kuna, Idaho. The East Kuna Off-Site Infrastructure scope of work includes construction of...

IMCO was contracted by The Boeing Company to replace the Everett manufacturing facility’s primary stormwater treatment system in response to updated Department of Ecology discharge standards requiring a higher level of treatment prior to releasing water into the adjacent...

Over multiple contracts, IMCO made significant upgrades to Darigold’s Boise wastewater treatment plant. In early 2022, Darigold selected IMCO for a design-build contract to construct a new dissolved air flotation (DAF) system to further treat and improve the plant’s...

In February 2021 the existing bulkhead wall at the Foss Maritime shipyard in Seattle began deflecting into the ship canal. The uplands behind the wall were excavated and large concrete blocks were used to hold the wall back to...

This project involved the rehabilitation of 2,500 linear feet of the Tolt Pipeline No. 1 using 54-inch HDPE pipe installed by slip-lining. The scope included connections to an existing 66-inch pipeline, installation of blowoff valves and chambers, construction of...

Perpetua Resources, headquartered in Boise, Idaho, has been working on the Stibnite Mine Gold Project since 2010. This historic site includes one of the highest-grade, open pit gold deposits in the U.S. Perpetua has created a plan for this...

IMCO Construction brought improvements to the industrial wastewater treatment plant at Darigold’s Caldwell butter plant to allow discharged waste to remain compliant with environmental requirements. Construction crews demolished an existing storage building and constructed a new dissolved air flotation...

The Lewiston water treatment plant retrofit project has been recognized by the DBIA with a National Award of Merit in the water/wastewater category. IMCO’s progressive design-build team used a creative approach to construction, employed the benefits of the progressive...

Located in the beautiful foothills northwest of Boise, the town of Eagle is experiencing rapid growth and expansion. IMCO expanded the existing wastewater treatment system with two new aerated lagoon cells and two new settling lagoon cells, resulting in...

The Skagit River Pipeline Replacement and Clearwell Construction project included the construction of a new raw water pipeline and a new water storage tank (clearwell). IMCO crews installed a 42-inch diameter pipeline up to 50 feet below the riverbed...

This project involves the demolition of the water pollution control facility (WPCF) final effluent north (FEN) sodium hypochlorite storage and feed facility, and construction of a new facility to replace it. Construction of the new facility includes modifications to...

IMCO Construction provided extensive upgrades to the existing wastewater treatment plant for the City of Priest River, Idaho. The project brought the facility up current environmental standards and included influent lift station upgrades with screw pump replacement and the...

IMCO constructed a new mine water treatment plant at the site of an abandoned copper mine in remote central Washington, near Lake Chelan. IMCO’s client, global mining giant Rio Tinto, is responsible for the clean up of the mine...

The Priest Rapids Hatchery Renovation project provided extensive upgrades to an existing hatchery to improve reliability and ease operation, maintenance, and monitoring of Chinook salmon rearing.   All construction work had to be strategically phased to avoid impacts to the...

IMCO was the general contractor and construction manager (GCCM) working with Carollo Engineers to add nearly 30% plant capacity. The facility treats wastewater from the cities of Everett, Mukilteo, Alderwood, and Silver Lake to keep the local rivers, lakes, and...

The project provided extensive improvements and upgrades to Arlington’s existing treatment facility. Work included relocation of utilities, new electrical, natural gas, and water services, demolition of existing buildings and structures, the placement of 5,000 cubic yards of structural concrete,...

IMCO used innovative methods to reuse existing infrastructure in order to construct a new combined sewer overflow project for the City of Port Angeles. The Project was part of the City’s approved CSO Reduction program to increase storage capacity...

This project constructed a new 42 million gallon per day water treatment plant for the City of Anacortes.  The new treatment facility treats water from the Skagit River and serves the 56,000 customers in the City of Anacortes, La...

The project included construction of a new storm water conveyance and storage system in the Madison Valley basin in Washington Park.  Designed to greatly reduce the potential for flooding, the new storage system in Washington Park holds approximately 1.3 million gallons of storm water...