FAQs — MALIBU CREEK ECOSYSTEM RESTORATION PROJECT

The Malibu Creek Ecosystem Restoration Project (MCERP) involves the removal of the decommissioned Rindge Dam along Malibu Creek, removal of approximately 780,000 cubic yards of sediment behind the dam, and modification/removal of eight upstream barriers along Las Virgenes and Cold Creeks within the Malibu Creek watershed. When completed the project will restore creek ecosystem functions and increase habitat connectivity, including opening 15 additional miles of stream habitat for the endangered southern California steelhead (Oncorhynchus mykiss), improve climate resiliency, and restore natural sediment transport processes that will nourish our beaches with vital sand.
The project is currently funded through 90% of the total cost by appropriations from the California State Legislature. The construction phase of the project is not currently funded. The previous study estimated the construction cost to be $280 million, but this estimate will be reevaluated and updated in the current design phase of the project.
Phase II is the pre-construction, engineering and design phase of the restoration project that includes technical studies for sediment transport analysis, surface flow modeling, preparation of the engineering plans for barrier removal or remediation, logistics planning, environmental planning and permitting, and public outreach.
Over the next three years, State Parks will lead Phase II with completion of the phase slated for March 2026.

Malibu Creek was once abundant with Southern steelhead. After the 18-mile waterway is restored, state and federal agencies and regional experts on steelhead will establish a steelhead management plan to consider active reintroduction of the species or monitoring for potential passive recolonization. Dam removal will greatly advance their recovery in the watershed.
Post dam removal, all species will benefit with a more resilient ecological habitat and improved migration corridors. Endangered species, such as Southern steelhead, red-legged frog, and pond turtle, will have improved habitat for breeding.
Although there is native, riparian vegetation immediately above the dam such as sycamores, removing the dam and its sediment and opening up 15 additional miles of habitat for aquatic and terrestrial species outweigh loss of existing riparian vegetation as re-establishment and reconnection.
Enhancing natural sediment transport processes as well as lagoon and river ecosystem function are objectives of the project. The project will incorporate preparation of monitoring and adaptive management plans for the creek, lagoon and beach.

Analysis of flooding is a critical part of the current phase of the project. Currently, the dam and upstream barriers proposed for removal do not provide significant flood attenuation or retention of sediment. Due to the low slope of the stream near Malibu and lack of sediment retention at the dam, sediment will continue to be deposited downstream with or without dam removal.
Low sloping areas prone to flooding will factor into the design process as well as evaluating bank stabilization for these areas, particularly in residential areas.
While the dam and upstream barriers currently do not provide significant flood attenuation, an analysis of flooding in commercial and residential areas and their access points is a critical part of the current project phase.

Sediment removal, transport, and beneficial distribution options were defined in the Locally Preferred Plan approved in 2020. We will also review whether more material of various grain sizes can be deposited in the nearshore environment than previously assumed.
Phase II includes evaluating effects of sediment deposition and future accretion at the beach and impacts to the surf break. Enhancing natural sediment transport processes are objectives of the project.
Impacts to vegetation and habitat as a result of dam removal will also be considered. The current phase of the project will also evaluate effects of sediment beneficial re-use options along the lower creek and lagoon, as well as biodiversity in the lagoon. Both the Malibu Creek Lagoon and Adamson House are public lands and protecting them is a significant part of the design phase, including finding ways to bring more erosion protection to the Adamson House and more ecological resiliency to Malibu Lagoon.

Sediment removal, transport, beneficial re-use options, and access road options will be evaluated to reduce trucking distance and the number of truck trips in this current phase.
Seasonal and peak traffic hours will be studied and the scheduling of construction and sediment transport trucks will be arranged around peak commuting and traveling conditions.
The construction schedule will be posted on https://www.parks.ca.gov/mcerp when the actual construction begins.