Rindge Dam removal advances to pre-construction, engineering, and design phase

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This overhead photo and diagram shows the area that will be affected by the Rindge Dam removal project. Contributed Photo

Calling it the Malibu Creek Ecosystem Restoration Project, State Parks is now funded and ready 

The feasibility study to permanently remove Rindge Dam, about three miles up Malibu Creek from the ocean and downtown, was originally commissioned back in 1992. A lot of locals didn’t believe it would ever happen, because it would be such a huge, expensive, long-term project — a government pipe dream. From time to time over the decades, California State Parks, along with co-partner U.S. Army Corps of Engineers (USACE), would make presentations and collect public comments about the project, but never provide much in the way of updates.

Well, last Tuesday, April 25, California State Parks made a big announcement: It’s happening, and the pre-construction, engineering, and design phase (PED) of the project is now starting. A public workshop on the PED phase will be scheduled in the coming months.

“The Malibu Creek Ecosystem Restoration Project is a critical priority for State Parks, our partners, and the community. The project helps preserve California’s unparalleled biodiversity, increases and reconnects critical habitat, and mitigates the impacts of climate change,” State Parks Director Armando Quintero said in a prepared statement. “We’re proud to lead this significant restoration project that will protect the heart of Malibu Creek State Park and Malibu’s famous beaches. We look forward to this next phase of close collaboration with our project technical team members and community partners to achieve this monumental State Parks-led project.”

The project will involve the removal of the decommissioned Rindge Dam on Malibu Creek along with about 780,000 cubic yards of sediment accumulated behind the dam. Eight upstream barriers, mostly culverts that block fish migration along Las Virgenes and Cold creeks, will also be modified or removed. The dam arch will be lowered concurrently with removal of the impounded sediment over a time period of about eight years, beginning in 2025.

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The Malibu Creek Ecosystem Restoration Project will involve the removal of the decommissioned Rindge Dam on Malibu Creek along with about 780,000 cubic yards of sediment accumulated behind the dam. Contributed Photo

The plan calls for direct truck transport of one-third of the sediment mined from the Rindge Dam to go up Malibu Canyon/Las Virgenes Road, to Lost Hills Road, U.S. Highway 101 and on to Ventura Harbor, about 41 miles away from the dam. The sediment is predominantly sand, and will be tested, transferred to barges, shipped down the coast, and carefully placed along the Malibu shoreline east of the pier, with care taken to avoid damage to nearshore kelp beds.

“Wave action, currents and tides will quickly disperse the sediment, predominantly in a downcoast direction,” State Parks stated. 

The other two-thirds of the sediment will be trucked north to the Calabasas Landfill, about 7.4 miles from the dam site.

State Parks states that removing the dam and sediment will “restore creek ecosystem functions and increase habitat connectivity, including re-opening 15 miles of stream habitat for the highly endangered Southern California steelhead trout,” which returns from the ocean as an adult to swim upstream and spawn. Other restoration benefits include improving climate resiliency and restoring natural sediment flows to the ocean that will naturally nourish local beaches with more sand.

State Parks also pointed out some obvious improvements in public safety — the obsolete dam was the site of numerous serious injuries and even fatalities from park visitors jumping off the spillway and it was finally declared off-limits to the public in 2014. But even as recently as 2020, a young man fell 60 feet to his death from the top of the dam.

The project was, and still is, controversial among some Malibu residents — some have argued that the dam should be preserved as a California Historical Landmark. Some surfers fear that free sediment flow could somehow ruin the surf break at Surfrider Beach, and some residents and business owners in the flood plain, in the Serra Canyon and Civic Center areas, express concerns over possible flooding if the dam is removed (experts say there is no more chance of flooding without the dam than there is with the current dam).

Rindge Dam is a 100-foot-tall concrete structure privately built by hired workers of May Knight Rindge, who owned all of Malibu at the time. The main concrete arch of the Rindge Dam was completed in 1924, and the spillway in 1926. Originally intended for flood control and water storage, the dam no longer performs either of those functions — the reservoir filled up with silt over 80 years ago. The dam was decommissioned in 1967, and purchased shortly thereafter by State Parks as part of Malibu Creek State Park.