Watershed Drainage By 13StarsManager - February 16, 2017 0 539 FacebookTwitterPinterestWhatsApp The watershed drainage area above the Rindge Dam covers about 110 square miles in Los Angeles and Ventura Counties. It is the largest coastal watershed in the Santa Monica Mountains. Share this: Share on Facebook (Opens in new window) Facebook Share on X (Opens in new window) X Like this:Like Loading... Related