Restoring Resilient and Connected Riparian Stream Corridor Habitat on the Santa Clara River

The Santa Clara River (SCR) flows through northern Los Angeles and Ventura Counties, at the junction of 5 Bioregions, retains much of its hydrological integrity, and sustains over 18 federally listed species. However, the SCR faces numerous ecosystem stressors, including habitat loss and inputs from intensive agriculture and urbanization, and invasion by numerous non-native plant and animal species. The project area is approximately 16 river miles within the floodplain of the SCR in Ventura County roughly between the confluences of Sespe and Santa Paula Creeks. The Santa Paula-to-Sespe Conservation Area geographic scope includes the area from the SCR upwelling zone upstream of Fillmore to just below the Freeman Diversion in Saticoy. This reach of the SCR is designated as Critical Habitat for southern steelhead trout and the Sespe reach is also identified as a Wild & Scenic River.

This project will restore 334 acres of riparian habitat on conservation properties throughout the middle Santa Clara River, Ventura County, CA. The Santa Clara River is considered one of the four largest rivers with a significant contribution to Southern California anadromous steelhead populations and thereby is important to regional and species resilience and a Core 1 priority for restoration and recovery (National Marine Fisheries Service 2012). This work will build on recent and ongoing restoration efforts to create large, contiguous tracts of high-quality and diverse riparian and instream habitat to benefit wildlife, ecosystems, and humans. The project is focused on the restoration and enhancement of migratory corridor habitat supporting the recovery of Southern California steelhead (DPS) including active river channel, off-channel wetlands, artesian surface water features and riparian forest. Objectives include invasive vegetation (Arundo donax) removal, active riparian forest restoration, and land conversion from agriculture to riparian forest to facilitate the reconnection of artesian surface water features to the active river channel. The project will use management of invasive plants and revegetation to reestablish habitat complexity of a variety of endemic riparian habitat types. The project sits between two steelhead barrier removal projects in advanced planning on the Santa Clara River and tributaries. The Freeman Diversion fish passage improvement project and Multiple Species Habitat Conservation Plan (United Water Conservation District) and the Harvey Diversion Fish Passage Remediation Project (Caltrout) will enhance access to migratory and spawning habitat significantly enhancing recovery opportunities for Southern steelhead in the Santa Clara River and tributaries. This project takes advantage of natural flood disturbance during the winters of 2023, 2024 to reclaim and increase high quality riparian habitat, enhance resilient instream flows, build-in climate resilience and enhance habitat refugia for aquatic and riparian dependent terrestrial species.

Initial restoration has been completed on over 1200 acres of high-quality riparian habitat. A feasibility study is underway for the transition of floodplain agricultural land to riparian habitat and the enhancement and creation of emergent wetland habitat. The project will focus on final planning and implementation of constructed wetland features.