premise: Carneros Creek is a southward flowing stream originating in the Santa Ynez Mountains, in Santa Barbara County, California. It flows to Lake Los Carneros Park, under U. S. Highway 101 where it runs in a man-made channel diverted to the west of Santa Barbara Municipal Airport, until it meets Goleta Slough, from whence its waters flow to the Santa Barbara Channel of the Pacific Ocean.
hypothesis: Carneros Creek is manmade.
reason: Its not clear if it is natural or manmade.