A major tributary of the Middle Eel, the Black Butte River was added to the federal system by Congress in 2006, with the passage of the Northern California Coastal Wild Heritage Act, which also protected more than 265,000 acres of wilderness. The protected segments include 19.5 miles of the Black Butte River to its confluence with the Middle Eel, and 1.5 miles of its tributary, Cold Creek. The Black Butte River possesses outstandingly remarkable fish and Native American cultural values. The river provides important spawning and rearing grounds for resident trout and anadromous fish, including critical habitat for threatened and endangered coho salmon and steelhead. Cold Creek is an important source of cold water for the river’s fisheries. The river also possesses some of the most concentrated and significant Native American cultural values on the Mendocino Forest.