In 1948, over many objections and reservations, construction of a dam on the Ventura River was completed. It's stated purpose was water storage and flood control. Even from the conceptual stage, it was not clear that the dam would serve those ends. However, what became painfully clear soon afterward, were two environmental tragedies: disastrous decline of steelhead fisheries and starvation of beaches normally fed by sediments of the Ventura River.
Now, half a century later, the capacity of the Matilija Reservoir has been reduced by over 90%, a result of the entrapment of six million cubic yards of sediment. With its crumbling concrete and silt filled reservoir, Matilija Dam no longer serves any beneficial purpose. The Ventura River sleeps behind the dam. With its removal, ocean-going fish will again be able to use the river to spawn, and the beaches will be able to feast on sediments transported down the river from the steep canyons of Matilija Creek. The time has come to undo the damage of that bad idea. It's time to take it down.
At almost 200 feet, Matilija is the largest dam ever considered for removal. There are many lessons to be learned. Preliminary studies have determined that although deconstructing the dam itself is fairly straightforward, the huge quantity of sediment filling the reservoir presents a much bigger challenge. If released all at once, the river downstream would suffer devastating floods. How and where to transport the sediment is the big question, and several options are being considered. Initial estimates range from $20 to $180 million. Further studies are needed to ensure that the complete removal of the dam is carried out in a safe and environmentally sound manner.
There is overwhelming support for removing Matilija Dam, and a broad coalition of local, state, federal, and private agencies are working to secure the funding and congressional support needed to complete the project. Click Here for the latest updates.