LA County outlines $27 million living-shoreline plan and 300,000-cubic-yard beach nourishment for Redondo Beach

The Los Angeles County Department of Beaches and Harbors presented a living-shoreline demonstration project for Redondo Beach that would place about 300,000 cubic yards of beach-quality sand, create roughly 0.5 acre of dune habitat and widen the beach by about 90 feet, county staff said during the Harbor Commission meeting.

County coastal resilience project manager Emiko Innes said the project area lies between the Redondo Beach Pier and the Topaz groin and that county modeling shows most sediment near the beach is lost to the nearby Redondo Submarine Canyon rather than migrating north under the pier. “This will make the beach width 90 feet wider than current condition,” Innes said, describing the proposed nourishment envelope and the dune habitat element.

The county described the project cost as about $27,000,000 and staff cited a benefit–cost ratio of 7.5. Innes said the current feasibility study is expected to finish in July 2025 and that subsequent phases will include preliminary engineering, environmental review and permitting; graphic design and outreach; and coordination with the U.S. Army Corps of Engineers to pursue beneficial reuse of dredged material from Marina del Rey.

Nut graf: County staff framed the plan as a nature-based alternative to harder shoreline structures and part of a broader coastal-resilience initiative. Commissioners and local users pressed the county on sediment sources, screening and testing for trash and chemicals, and operational details for dredging and sand transport — issues that county staff said would be addressed in the next-phase studies and in multi-agency review.

Commissioners, harbor managers and several local residents questioned whether sand dredged from Marina del Rey would be suitable. Commissioner Carlson and others recounted a prior dredging event in which small plastic debris appeared in nearshore areas; Commissioner Collier described diving observations that debris and small items collected near the canyon. County consultant Chris Webb of Moffatt & Nichol said offshore “borrow” deposits are typically tested with vibra-core borings and laboratory grain-size and chemistry analyses before any material is approved for beach placement. Webb described sampling procedures, grain-size matching and the multi-agency Southern California Dredged Material Management Team (DMMT) screening process.

County staff emphasized that dredged material used for nourishment would have to meet “beach-quality” standards and would be cleared through the DMMT and permitting agencies. Innes said the county has increased monitoring and screening since the 2012 dredging and that chemical testing and trash-screening standards are part of project planning. “We completely agree that plastic trash . . . is not acceptable,” Innes said.

Speakers and public commenters urged the county to consider smaller, more frequent placements or to use locally available material removed from King Harbor and maintenance dredging deposits rather than larger, infrequent projects. Commissioners and members of the public suggested staging options that could use locally stored sand to reduce transport costs and avoid bringing lower-quality material to Redondo Beach.

County consultants described two dredging methods: a cutter-head suction dredge that can operate nearshore and pump sand ashore, typically less expensive per cubic yard, and a hopper dredge that stores material aboard and pumps ashore but may require mobilization from other coasts, increasing costs. Webb gave a rough range: cutter-head-dredge placement can be “on the order of $15 to $20 per cubic yard,” while hopper-dredge mobilization could raise unit costs substantially. County staff said the project budget includes contingencies and that final unit costs depend on the borrow source and dredge type.

The Harbor Commission voted to receive and file the county presentation; commissioners did not approve any construction action at the meeting. County staff and consultants said the feasibility study will be completed next month, followed by design, permitting and sampling work that will be reviewed by interagency groups and the public.

Ending: County staff asked stakeholders and city staff to continue coordination as the regional coastal strategic adaptation plan and the county’s SCOOP (sound compatibility and opportunistic use program) are finalized; Redondo Beach is one of five preapproved opportunistic-receiving sites, the county said. The presentation and the questions raised indicate the project will move into technical sampling and regulatory review before a construction decision is made.