The Current Magazine Summer 2015 | Page 17

Restoration to Promote Recovery of Southern California Steelhead in the Santa Clara River Watershed

Santa Paula Creek and its tributary Sisar Creek, together host the most productive steelhead habitat in the entire Santa Clara River watershed (Stoecker and Kelley, 2005). It is imperative that fish have access to this spawning and rearing habitat for the population numbers to improve. The Santa Clara River watershed is not only important on a local level as a Core 1 watershed in the Monte Arido Highlands Biogeograpic Population Group (BPG) , but was named the Southern California regional Salmonid Stronghold for Southern California steelhead (O. mykiss) by the Wild Salmon Center (National Marine Fisheries Service, 2012).

The Harvey Diversion Fish Passage Restoration Project is located 3.6 miles upstream of the confluence of Santa Paula Creek and the Santa Clara River, north of the city of Santa Paula, alongside Highway 150. The California Department of Fish and Wildlife’s Passage Assessment Database lists the diversion as a complete fish passage barrier.

While diversion of water from Santa Paula Creek for agricultural purposes began as early as 1860, the current Harvey Diversion was built in 1910. Over time, the scouring effect of falling water caused the elevation of the creek bed below the Diversion to decline significantly. A concrete and steel, 23 foot “jump box” fish ladder was attached to the Diversion. It was originally constructed in 1939, rebuilt in 1950, and then completely rebuilt as a reinforced concrete fish ladder in 2000. As the creek has continued to erode downstream of the diversion structure, additional steel jump boxes have been added on the downstream end of the ladder. Storms, erosion and sediment have continued to add to the problem.