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Trout hatcheries are important elements in the maintenance of productive trout fisheries in habitats where fishing pressure exceeds the natural productivity or where otherwise productive areas lack the spawning conditions essential to fulfillment of the complete life cycle of the fish. Man-made lakes, such as some of the reservoirs to be constructed in the Pacific Southwest Water Plan, will develop waters of a temperature suitable for the growth of trout. Releases from the lower depths of reservoirs will create flows of cool water in the streams below dams which may be ideal for growth of trout. However, these waters may lack the conditions necessary for natural reproduction by these stream-spawning species. In such instances, high quality trout fishing may be attained through stocking young fish or larger catchable-sized ones where exceptionally heavy pressure may be encountered. Exceptionally fine trout fishing new exists in the Colorado River below Lake Mead and below Lake Mohave. The cold waters released from Lake Mead make possible a good trout fishery only in the upper and lower reaches of Lake Mohave. Warmwater species predominate in the lake proper between Eldorado Canyon, where the cold waters slide under the warmer surface waters, and the lower reaches of the lake, where the cold density current from Lake Mead is forced upward along the face of the dam. Without trout stocking, these waters would not be as productive as they are today. The new coldwater fish hatchery to be located at a site yet to be determined in the Lower Colorado River Basin will be designed to help maximize opportunities for good trout fishing in suitable waters of the basin created by the Pacific Southwest Water Plan. Its estimated cost is $1,200,000. The precise location and other physical characteristics will be determined following authorization of the Plan and prior to construction. If the Helena Reservoir is eventually constructed on the Trinity River, it is proposed to convert the existing Trinity River salmon and steelhead hatchery to trout production. This hatchery, built by the Bureau of Reclamation to mitigate effects of Trinity River Division, Central Valley Project, and operated by the State of California under contract, will no longer be adaptable to its present use once Helena Dam and Reservoir are built. Capacity is included in the proposed Helena Hatchery to replace the production of anadromous fish now carried out at Trinity River Hatchery. 44Epson Perfection 4870 Photo, 400 dpi, 8 bit, 13,961,216 byte