Watershed Drainage By 13StarsManager - February 16, 2017 0 421 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: Click to share on Facebook (Opens in new window) Facebook Click to share on X (Opens in new window) X Like this:Like Loading... Related