Malibu Creek Ecosystem Restoration Feasibility Study
Draft Integrated Feasibility Report (IFR) with Environmental Impact Statement/ Environmental Impact Report and Appendices
A Draft Integrated Feasibility Report (IFR) that includes an integrated Environmental Impact Statement/Environmental Impact Report (EIS/EIR) has been prepared by the U.S. Army Corps of Engineers (USACE) and the California Department of Parks and Recreation (CDPR) for the Malibu Creek Ecosystem Restoration Feasibility Study. The EIS is being filed with the Environmental Protection Agency and is being made available to interested parties for review and comment pursuant to regulations of the President's Council on Environmental Quality for implementing National Environmental Policy Act (NEPA) (40 CFR Parts 1500-1508). The Draft EIR has been prepared jointly with the EIS and notice is hereby given, in accordance with the California Environmental Quality Act (CEQA) [Public Resources Code §21000, et seq.] and the 2015 State CEQA Guidelines [California Code of Regulations §15000, et seq.]. The USACE is the Lead Agency for NEPA and the CDPR is the Lead Agency for CEQA.
The study has identified several problem areas.
- Loss of connectivity to good-to-excellent quality aquatic spawning and rearing habitat for migratory species, and disturbances to adjacent riparian habitat due to the construction of Rindge Dam and other upstream road crossings and small dams, isolating reaches of Malibu Creek and tributaries in the watershed.
- Disruption to historic migratory paths for mammals due to the construction of Rindge Dam and other upstream road crossings and small dams, isolating reaches of Malibu Creek and tributaries in the watershed.
- Reduction of natural sediment delivery during storms to reaches of Malibu Creek and tributaries, the Malibu Lagoon, Pacific Ocean shoreline, and nearshore environments for over 90 years due to the construction of several water supply and recreational dams in the watershed.
- Changes to the natural creek slope in the vicinity of Rindge Dam as a result of dam construction and associated sediment deposition have lowered base flow velocities, altering vegetation types and raising water temperatures, adversely affecting the aquatic habitat quality by adding stressors to native species.
The purpose of the study is to establish a more natural sediment transport regime from the watershed to the Southern California shoreline in the vicinity of Malibu Creek within the next several decades, reestablish habitat connectivity along Malibu Creek and tributaries in the next several decades to restore migratory access to former upstream spawning areas for indigenous aquatic species and allow for safe passage for terrestrial species from the Pacific Ocean to the watershed and broader Santa Monica Mountains National Recreation Area, and restore aquatic habitat of sufficient quality along Malibu Creek and tributaries to sustain or enhance indigenous populations of aquatic species within the next several decades. Alternatives have been developed to identify what the USACE and CDPR partnership wants to achieve with the alternatives and accomplish with a plan.
Study Area/Project Area
The Malibu Creek watershed is located approximately 30 miles west of downtown Los Angeles, California. Approximately two-thirds of the watershed is located in northwestern Los Angeles County and the remaining one-third is in southeastern Ventura County. The watershed drainage area is approximately 110 square miles and includes areas of the Santa Monica Mountains and Simi Hills. Elevations in the watershed range from over 3,100 feet at Sandstone Peak in Ventura County to sea level at Santa Monica Bay. It is the largest coastal watershed in the Santa Monica Mountains, and is encompassed by one of the largest areas of protected open space left in southern California, the Santa Monica Mountains National Recreation Area, managed by the National Park Service.
The study area includes Malibu Creek and tributaries, and shoreline and nearshore locations outside of the watershed. Malibu Creek runs along a generally southern route through the watershed for about 10 miles before draining into Malibu Lagoon and the Pacific Ocean. Primary tributary flows into Malibu Creek in the lower portion of the watershed are from Las Virgenes Creek and Cold Creek. A variety of streambed modifications are evident throughout the watershed, particularly in the upper, urbanized areas. However, the majority of the streambed in the study area remains unimproved (i.e., is not armored with stone or concrete on bank or bed), though at times natural meanders of the creeks are constricted by roads and other development.
Malibu Canyon Road/Las Virgenes Road runs generally parallel to Malibu Creek through the watershed, from Pacific Coast Highway (PCH) past Interstate Highway 101. This road is one of the only major traffic arteries through the Santa Monica Mountains, connecting coastal route (PCH) to the San Fernando Valley.
Potentially Significant Effects
The Draft IFR identifies potentially significant environmental effects in the following areas: traffic, water quality, air quality, biological resources, cultural resources, aesthetics, and noise. No hazardous sites subject to Section 65962.5 of the California Government Code are known or expected to be in the project area.
The lead federal agency for this study is the USACE, Los Angeles District, in coordination with the non-Federal study Sponsor, the CDPR. Multiple other agencies have and continue to contribute to this study effort.