The Mitchell Act was enacted in 1938 to provide for conservation of anadromous (salmon and steelhead) fishery resources of the Columbia River. The program has evolved into three primary components:

• Operation of 18 fish hatcheries (from a high of 25 hatcheries and major rearing ponds) releasing 63.6 million juvenile anadromous fish in Oregon and Washington.
• Construction, operation and maintenance of more than 700 fish screens at irrigation diversions to protect juvenile salmon and steelhead in Oregon, Washington and Idaho.
• Ongoing operations and maintenance of 90 fishways enhancing adult fish passage to nearly 2,000 miles of stream habitat in all three states.

Historically, production from the program has provided fish for tribal treaty fisheries in the Columbia River, and for ocean and in-river recreational and commercial fisheries. Renegotiation of the Columbia River Fish Management Plan per U.S. v. Oregon includes this program.

With application of the ESA throughout the Columbia River Basin, substantial changes have been, and will continue to be required of the Mitchell Act Program. Overall hatchery production has been reduced from more than 100 million to 63.3 million fish. An environmental impact statement (EIS) is being prepared to evaluate the effects of the funding and operation of Mitchell Act hatcheries. Hatchery reprogramming efforts are under way to revitalize restricted fishing opportunities by creating selective fisheries for marked hatchery fish, and terminal fisheries on hatchery-only fish.