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-, ~, _ , Temperature emergencies Temperature emergencies have been the norm on California's developed rivers, particularly the Trinity. These emergencies occur in part because there is insufficient water dedicated to the river to moderate the natural warming during the late summer when the Trinity salmon eggs incubate. Drought periods - common in recent years - result in ever lower flows that exacerbate the late summer temperature problems. Lethal temperatures at these critical times not only destroy a year's stock of young salmon, they effectively waste all of the water that has been allocated to fishery maintenance during the preceding water year. Trinity River Basin, California From its headwaters in the impressive Salmon-Trinity mountains in northwestern California, the Trinity River flows 200 miles to the Pacific Ocean, draining over 2,900 square miles of mountainous and forested land. Historically, the Trinity River supported one of the premier anadromous fisheries in the United States. A tributary to the Klamath River, the Trinity contributed half to one-third of the total number of salmon originating from the Klamath-Trinity River Basin, California's top steelhead-producing region and second-largest salmon-producing region after the Sacramento River basin. The Hoopa, Yurok and Karok tribes occupied lands along the river and de- pended on the fishery for their subsistence. In the late 1800s, the estimated annual run. of chinook salmon adults was between 150,000 and 200,000, with an additional 50,000 steelhead and 5,000 coho salmon. This natural phenomenon ended after the turn of the century. The exceptional fishery was reduced to a mere remnant by human activities, such as the canning industry that peaked in 1919, mining and logging, and most importantly, federal water diversions by the Central Valley Project (CVP). The CVP ensured 24 that the Trinity basin would be forever changed. The construction of Trinity and Lewiston Dams forty years ago eliminated 109 miles of anadromous fish habitat, including 59 miles of chinook salmon spawning and rearing habitat. The river lost 80% of its flow and 90% of its anadromous fish production to out-of- basin diversions amounting to 1,000,000 acre-feet of water annually, to irrigate drylands in the Central Valley farming region of California. Basin of Origin Water In 1990, the Natural Heritage Institute (NHI) began assisting Trinity County, as its special counsel, in developing a pro- gram for repairing the fishery resources of the Trinity River watershed. The broad objective of the project was to demonstrate an effective means for impoverished rural communities in the West, such as Trinity County, to obtain priority access to the waters that originate in their basins and are critical to their long-term environmen- tal protection and economic growth. The Trinity River watershed is just one of the economically depressed and water- dependent local economies in the western United States whose future depends upon