Sonoma Creek is a stream in northern California. It is one of two principal drainages of southern Sonoma County, California, with headwaters rising in the rugged hills of Sugarloaf Ridge State Park and discharging to San Pablo Bay, the northern arm of San Francisco Bay. The watershed drained by Sonoma Creek is roughly equivalent to the wine region of Sonoma Valley, an area of about . The State of California has designated the Sonoma Creek watershed as a “Critical Coastal Water Resource”. To the east of this generally rectangular watershed is the Napa River watershed, and to the west are the Petaluma River and Tolay Creek watersheds. This south flowing river drains the western slopes of the Mayacamas Range, the southern slopes of Annadel State Park and the eastern slopes of the Sonoma Mountains with intermittent winter flows in the higher tributary reaches. As the tributaries and headwaters reach the valley floor, a perennial stream cuts through scenic and valuable vineyards of Kenwood. Sonoma Creek veers west at Kenwood and cuts a gorge running parallel to Warm Springs Road, where it turns south to historic Glen Ellen, passing within one mile (1.6 kilometers) of Jack London State Historic Park and the Wolf House and thence southward paralleling Arnold Drive. In the city of Sonoma it is an urban creek which emerges into agricultural areas to the south. Finally, Sonoma Creek discharges to the vast Napa-Sonoma Marsh at the northern tip of San Pablo Bay. Principal tributaries to the creek include Yulupa Creek, Graham Creek, Calabazas Creek, Bear Creek, Schell Creek, and Fowler Creek. Headwaters Headwaters rise on the west facing slopes of the inner coast southern Mayacamas Mountains, where the highest peaks are Hood Mountain, elevation 2750 feet (833 m) and Bald Mountain, elevation 2729 feet (826 m), each of which has views of the Pacific Ocean and the Sierra Nevada range. The headwaters cut through gorge and meadow of Sugarloaf Ridge State Park, which boasts 25 miles (40 kilometers) of self-guided trails and the Robert Ferguson Observatory. There is also a 25 foot (eight meter) high waterfall, present only when fed by the winter rains but can persist until late May for high rainfall years such as 2006. In the 100 foot (30 m) deep gorge into which the waterfall spills is a moist mixed forest habitat including California bay laurel, coast redwood, Douglas fir, big leaf maple, cherry