From Sunset Cliffs to Oceanside, San Diego County is embarking on a sea change in efforts to protect the coast.
The seawalls, jetties and rip-rap that have been deployed for generations to combat wind, wave and sea-level rise impacts are common features along the California coast. But those hard-armor strategies have fallen out of favor not only because their effectiveness came into question, but based on evidence that they were ultimately making things worse.
For years, the California Coastal Commission has been engineering a shift to nature-based coastal solutions and the cities of San Diego, Oceanside and Encinitas, among others, are putting them into practice. Imperial Beach, the low-lying coastal city to the south bounded by water on three sides, for years has been working on a sea-level rise plan that also has a focus on possible nature-based solutions.
Just last week, San Diego approved a broad Coastal Resilience Master Plan that calls for creating dunes with stabilizing vegetation in various locations, altering roadways and eliminating parking lots that have begun crumbling into the ocean and other measures to protect Sunset Cliffs and city beaches.
Oceanside is moving toward building two headlands on the beach to help hold the sand in place at a particularly eroded beach, along with an artificial reef nearby in the water to diminish the force of the waves.
Neither project is without dispute or logistical challenges.
Last year, San Diego approved a proposal to overhaul the recreational and natural areas in northeast Mission Bay, including the restoration and expansion of wetlands that can help absorb the rising sea and pull global-warming carbon out of the air.
Meanwhile, dune restoration several years ago in Encinitas is credited with protecting the coast from severe damage.
The long-discussed but relatively new nature-based approaches would supplement, not replace, sand replenishment efforts that occur on a regular basis up and down the coast. The Oceanside plan calls for putting up to 1 million cubic yards of sand on a few blocks of perhaps the city’s most threatened beach area.
The San Diego Association of Governments is in the initial stages of planning what would be its largest shoreline replenishment project ever, including for the first time San Clemente and Dana Point in southern Orange County, according to Phil Diehl of the Union-Tribune.
Sand replenishment is deemed a critical need to retain beaches that not only define the region but act as an economic driver and help blunt climate change-fueled sea-level rise.
Regional planners have even considered whether local agencies should buy a dredge rather than repeatedly hire private contractors to do the expensive jobs. Diehl reported that some members of a SANDAG advisory group on shoreline preservation were skeptical of whether purchasing the machinery was practical.
The coastal commission has considerable, if not absolute, power over development in the state’s “coastal zone,” which extends 3 miles offshore to a strip of land that varies in width along the seashore.
The commission’s “Sea Level Rise Policy Guidance,” updated late last year, lays out the basic rationale for nature-based adaptation strategies in the coastal zone.
The documents note that in addition to erosion, the sea-level rise is causing more extensive flooding, groundwater rise and wave damage of facilities and that planning for it is a “challenging and vital task.”
“Hard shoreline armoring, such as seawalls and revetments, have traditionally been used to protect coastal development,” the commission said. “But hard shoreline armoring can prevent coastal habitats like beaches, dunes, and wetlands from naturally shifting inland by fixing the shoreline and preventing sand from reaching the beach.
“This is typically called coastal squeeze because coastal habitats are squeezed out by shoreline development and hard armoring.”
The commission underscored the flexibility of nature-based projects, something echoed by officials in Oceanside and San Diego. The dunes, headlands and artificial reef can be adjusted or removed entirely if they prove ineffective.
Oceanside’s project, seen as a pilot for other cities to follow, was not met with universal acceptance at least initially, particularly by nearby coastal cities. But negotiations resulted in a compromise now moving forward.
In San Diego, some residents are skeptical that nature-based protections will do much to stave off erosion of Sunset Cliffs. And they expressed opposition to the proposal to turn the southern portion of Sunset Cliffs Boulevard into a one-way street and to charge for parking along the road.
As one of its case studies for a nature-based approach, the commission pointed to the “Cardiff State Beach Living Shoreline Project” in Encinitas where a restored dune system was constructed over buried revetments.
Without the project, the city of Encinitas said storm and wave action in January 2024 likely would have resulted in “significant flooding and undermining of South Coast Highway 101 that would have required extensive and very expensive repairs.”
The dunes were depleted but the system remained intact.
Ultimately, that’s perhaps the key goal of such coastline projects: to protect infrastructure and buildings from the encroaching ocean. That doesn’t necessarily do away with growing calls for “managed retreat,” the hotly disputed concept of eventually moving such structures further inland.
The difficulty — logistically, financially and politically — of moving the train tracks off the unstable cliffs in Del Mar is perhaps the highest-profile local example. Imagine when the push comes to do that for private property.
The costs for projects like those San Diego and Oceanside are planning will be substantial. The larger bill for broader protections against coastal erosion may be hard to imagine.
A study released last year by the University of Southern California predicts “Southern California’s coastal living costs will surge fivefold by 2050 as a direct result of beach erosion.”
San Diego is just getting its feet wet.