Robles Diversion Modifications

The Robles Diversion and Fish Passage Facility (Robles or Facility) is located on the Ventura River 2.3 miles downstream of the Matilija Dam. The Facility includes a 10-foot high diversion dam, forebay, fish ladder, intake screens, control gates, and the top section of a 4-mile long concrete channel known as the Robles-Casitas Canal.

Robles conveys water through the Canal from the upper Ventura River into storage in Lake Casitas for subsequent distribution to agricultural and municipal water users by the Casitas Municipal Water District. According to consumption reports, between 35-45 percent of Casitas’ users are agricultural users (this varies by year). Most of the water provided to consumers (83 percent) comes from Lake Casitas, and on average roughly one-third of that water comes from the Ventura River.

Originally constructed by the U.S. Bureau of Reclamation (USBR), two preferred alternative designs chosen by Robles Working Group stakeholders are currently being evaluated through a collaborative planning effort that includes consideration of options for enhanced maintenance, modernized infrastructure, and other agreed-upon upgrades to the Facility to support improved sediment transport before, during and after dam removal. The modifications will also address associated water supply and fish passage needs, as well as flood protection at Robles and for the nearby community of Meiners Oaks. A physical model based on the 10% design plans is being constructed by the USBR to assist in the further development and evaluation of the alternatives.