Seawalls and Coastal Armoring in Manhattan Beach, California
This page keeps the 'seawall & bulkhead' name for consistency with every other ocean market on this site, but the honest headline for Manhattan Beach is that hard coastal armoring -- private seawalls, bulkheads, riprap revetments -- is not the city's primary shoreline-protection story the way it might be in a bluff-lined or heavily engineered coastal market. California's own Coastal Act actively discourages new private armoring, and Manhattan Beach's own visible response to erosion, covered in depth on this site's beach-erosion page, is a nature-based dune restoration project rather than a hard-structure seawall program. This page explains why, and what the real permitting landscape looks like for anyone who does need to address shoreline protection on a specific parcel.
California's Coastal Act Deliberately Limits New Seawalls
The California Coastal Act generally permits new seawalls and similar shoreline-armoring structures only when required to serve coastal-dependent uses, or to protect existing structures or public beaches genuinely in danger from erosion -- and even then, only when designed to eliminate or mitigate adverse impacts on the local sand supply. Critically, shoreline and bluff protection structures are generally not permitted to protect new development: any permit for new construction on a blufftop or shoreline lot without existing protection must typically be conditioned with a deed restriction confirming no shoreline armoring structure will ever be built to protect that specific new development. As of 2026, the California Coastal Commission interprets "existing" structures (eligible for potential armoring protection under the Act's exception) as those lawfully built prior to January 1, 1977 -- meaning any Manhattan Beach structure built after that date has meaningfully more limited legal grounds to justify new shoreline armoring than an older, pre-1977 structure would.
Why California Restricts Armoring: The Beach-Depletion Tradeoff
The policy logic behind this restriction is well documented and directly relevant to why Manhattan Beach specifically has pursued dune restoration instead of hard armoring: seawalls and revetments can protect the specific private property behind them, but they do so by fixing the shoreline in place while the beach in front of them continues to narrow under wave action and sea-level rise, eventually depleting the beach itself, reducing public coastal access, and harming the shoreline sand-supply dynamics covered on this site's beach-erosion page. Given that Manhattan Beach has been independently identified as one of the more sand-loss-vulnerable beaches in Santa Monica Bay, a policy environment that discourages exactly the kind of hard armoring that would accelerate that beach-narrowing dynamic is a directly relevant, not abstract, consideration for this specific market.
Manhattan Beach's Actual Approach: Nature-Based, Not Hard Armoring
Consistent with that statewide policy direction, Manhattan Beach's own visible, currently operating shoreline-protection response is the Manhattan Beach Dune Restoration Project -- a roughly 3-acre native-dune restoration effort along North Manhattan Beach (23rd to 36th Streets), running since January 2022 in partnership with The Bay Foundation, LA County Department of Beaches and Harbors, LA County Fire Department's Lifeguard Division, and the California State Coastal Conservancy, covered in full on this site's beach-erosion page. This nature-based approach -- native vegetation, sand fencing, and wooden stakes designed to capture and retain windblown sand -- is explicitly a soft, living-shoreline strategy rather than a hard, engineered wall, consistent with both current coastal-resilience best practice and California's own Coastal Act preference against new hard armoring.
Existing Private Seawalls or Coastal Armoring: A Parcel-Specific, Not Citywide, Question
None of this means zero coastal armoring exists anywhere in Manhattan Beach -- California city and county governments collectively issue more than 1,000 shoreline-armoring-related permits annually statewide, reflecting that some existing structures, particularly older, pre-1977 construction, do carry legitimate legal grounds for protective structures. Whether any specific Manhattan Beach parcel -- particularly in the Sand Section or El Porto, closest to the shoreline -- has an existing seawall, revetment, or similar structure, and what condition or permit history that structure carries, is a parcel-specific fact this page cannot state generally; a buyer evaluating oceanfront or near-oceanfront property should ask directly about any existing coastal armoring on or near the specific parcel, its permit history, and its maintenance obligations, as part of standard due diligence.
What a Buyer Should Actually Ask
For a Manhattan Beach Sand Section or El Porto buyer, the practical due-diligence questions are: does the specific parcel or a directly adjacent one have any existing shoreline armoring, and if so, when was it built (before or after the Coastal Act's January 1, 1977 threshold) and under what permit; is the property subject to any deed restriction barring future armoring (common for newer coastal construction under the framework described above); and what role, if any, does the city's own dune-restoration project play in protecting that specific stretch of coastline. None of these questions has a citywide, one-size-fits-all answer -- they require checking the specific parcel's title history and permit records, and confirming current shoreline-protection status directly with the City of Manhattan Beach Community Development Department and, where Coastal Commission jurisdiction applies, the California Coastal Commission itself.
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Get a Free Agent Referral →Independent research. No ads. No sponsored listings. The California Coastal Act's general restriction on new seawalls (permitted mainly to protect existing structures or coastal-dependent uses, generally barred for new development, and requiring mitigation of sand-supply impacts), the required deed-restriction condition on new shoreline-lot development, the 2026 Coastal Commission interpretation of "existing" as pre-January-1-1977 construction, and the statewide figure of 1,000-plus shoreline-armoring permits issued annually by California cities and counties are drawn from Legal Planet's "Coastal Act Requires Strict Protection from Harmful Seawalls" (May 2025) and the California Coastal Commission's own "Coastal Armoring 101" guidance document. The general policy rationale connecting hard armoring to beach depletion and reduced public coastal access is drawn from the same Coastal Commission materials and Beachapedia's "State of the Beach" California shoreline-structures summary. Manhattan Beach's own dune-restoration response is detailed and sourced on this site's beach-erosion page. This page does not state whether any specific Manhattan Beach parcel currently has an existing seawall, revetment, or other coastal-armoring structure, its permit history, or any deed restriction affecting it, because these are genuinely parcel-specific facts not researchable at a citywide level and not confirmed for any individual Manhattan Beach address in researching this page. Confirm current, parcel-specific coastal-armoring status, permit history, and any deed restrictions directly with the City of Manhattan Beach Community Development Department, the California Coastal Commission, and a title company before making a purchase decision involving oceanfront or near-oceanfront property. Nothing on this page is legal or engineering advice.