The Santa Ynez River Watershed drains approximately 896 square miles. The river originates in the Los Padres National Forest and drains the northern slope of the Santa Ynez Mountains and the southern slope of the San Raphael Mountains.
It runs about 92 miles to the Pacific Ocean near Lompoc, California. Southern California steelhead trout were abundant in the river prior to the completion of the Gilbratrar Dam in 1920, which blocked passage to the upper watershed.
The Bradbury Dam (forming Cachuma reservoir) built in the early 1950′s, further impeded the return of the steelhead. Rainbow trout source populations still do exist above the Bradbury Dam.
Aside from barriers, water quality is also an issue on the river.