Robles Diversion Dam Fish
Screen and Fishway Project

Casitas Municipal Water District

Owned and operated by the Casitas Municipal Water District, the Robles Diversion Dam was substantially modified in 2003. As a result of steelhead rainbow trout becoming federally and state-listed as endangered species within the Ventura River ESU, the Casitas Municipal Water District is augmenting its existing facilities with fish passage provisions for both juvenile and adult migration.

The gravity diversion capabilities of the new diversion control and fish screen structures are designed by Wood Rodgers to accommodate up to 600 cfs. The fish screen features a chevron-configuration, vertical plate design with traveling brush mechanisms and adjustable velocity distribution baffles. The diversion control structure features a 20-foot wide by 10-foot high, single-leaf overshot gate and electronically controlled hoist assembly. A 300-foot vertical slot fish ladder will be constructed to convey a nominal 50 cfs with an auxiliary bypass pipeline to introduce supplemental “attraction” flow at the fishway entrance up to 100 cfs. The fishway also includes a bio-monitoring and trapping facility.