The Stanford Law School's Environmental and Natural Resources Law & Policy Program has released a report titled California Coastal Armoring Report: Managing Coastal Armoring and Climate Change Adaptation in the 21st Century . From its executive summary:
"In response to erosion and storm events, Californians have built seawalls, revetments, and other “coastal armoring” structures along significant portions of California’s coast. Coastal armoring now occupies more than 110 miles, or at least 10 percent, of the overall California coastline, including 33 percent of the southern California coastline. This coastal armoring has diminished California’s beaches and habitat, irreversibly altered bluffs, caused increased erosion to neighboring properties, and marred the natural beauty of the coast (emphasis added).
"A common perception is that seawalls and revetments protect the coast. Although such armoring structures may temporarily protect property from encroachment by the sea, they accelerate erosion of existing beaches and coastal habitats in the areas where they are located, limit beach access, and impede coastal recreation. Scientific evidence shows that coastal armoring structures prevent coastal ecosystems from migrating inland and cut off sand supply by preventing natural erosion processes. Put simply, when placed on an eroding or retreating beach, armoring structures will cause that beach to narrow and eventually disappear (emphasis added). Wave energy reflecting off of shoreline armoring structures also undercuts the beach and can hasten coastal erosion in front of the structure as well as on neighboring properties, harming those properties and stimulating yet more armoring.3 In short, many of California’s beaches, and the amenities and ecosystems they provide, may inevitably disappear due to armoring."
The report makes the following recommendations:
- Advance stronger statewide laws, policies, and funding mechanisms that discourage armoring and encourage non-armoring responses to erosion, storm events, and sea level rise. These responses include, where feasible and appropriate, natural protective infrastructure and relocating property away from coastal hazards.
- Ensure that local coastal planning mechanisms are used to incorporate a broader set of sustainable adaptation strategies and to discourage armoring.
- Support development and implementation of measures, including insurance programs and regulations, that require and/or incentivize private property owners to assume the risks of developing in high-hazard areas and that facilitate relocation away from hazardous areas.
- Where possible, pursue non-armoring responses to sea level rise and related coastal hazards for state-owned and private lands, such as relocating development (e.g., buildings, parking areas, roadways, utilities) and using other managed retreat strategies.
- Improve the availability of relevant data, guidance, and technical resources.