Matilija Dam, located in the Ventura River watershed on Matilija Creek north of Ojai, is a concrete arch dam built in 1947. Infamous for the scissors painted on the dam by graffiti artists in 2011 that have become an iconic symbol for dam removal, it was originally designed for water storage and flood control. … The Problem: The reservoir behind Matilija Dam is nearly completely clogged with sediment, significantly reducing storage capacity to the point that the dams is rendered non-functional. With no fish ladder or bypass structure present, it is a complete barrier to the migration of endangered Southern California steelhead.