Arroyo Sausal is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. The National Map, accessed March 10, 2011 northwest-flowing stream in Marin County, California. Its confluence with Salmon Creek is the start of Walker Creek which flows to Tomales Bay and thence to the Pacific Ocean.
History Arroyo Sausal is named for the Spanish 'grove of willows'. The watershed was part of the historical Rancho Soulajule, a Mexican land grant given in 1844 by Governor Manuel Micheltorena to José Ramón Mesa.Ogden Hoffman, 1862, Reports of Land Cases Determined in the United States District Court for the Northern District of California, Numa Hubert, San Francisco
Watershed and Course
Arroyo Sausal drains northwest through Canada Pomponio then west through Hicks Valley. After entering Soulajule Reservoir, it flows north to its confluence with Salmon Creek, and forms the beginning of the Walker Creek mainstem. The 310 acre Soulajule Reservoir drains a watershed of and its perennial outflow is maintained to benefit salmonids.
Ecology Historically, Arroyo Sausal's headwaters supported half of the Walker Creek watershed's coho salmon (Oncorhynchus kisutch) and steelhead trout (Oncorhynchus mykiss). These two salmonid species are federally endangered Central California Coast coho salmon evolutionary significant unit (ESU) and federally threatened Central California Coast steelhead trout distinct population segment (DPS) populations. However, an earthen dam built by a rancher in 1960s and then replaced in 1979 by construction of Soulajule Dam and reservoir (pronounced "Soo-la-HOO-lee") blocked these anadromous salmonid runs, eliminating of spawning habitat in upper Arroyo Sausal.
See also Tomales Bay Walker Creek List of rivers in California
References
External links Marin Water (formerly Marin Municipal Watershed District)