San Diego Coastline Faces Transformation Due to Super El Niño Threat
Experts warn of severe erosion, cliff collapses, and flooding that could permanently alter iconic locations.
San Diego's coastline is bracing for a significant threat from an approaching Super El Niño, which experts predict could lead to severe beach erosion, cliff collapses, and widespread coastal flooding. These combined forces have the potential to permanently alter the region's iconic shoreline.
Adam Young, a researcher at Scripps Institution of Oceanography at UC San Diego, explained that powerful waves associated with El Niño can accelerate erosion of beaches, sea cliffs, and bluffs. Concurrently, strong El Niño conditions can raise sea levels along the California coast by an estimated six to thirteen inches. "Combined, these factors increase coastal erosion and flooding during El Niño events, which can threaten public parks, beaches, critical infrastructure, highways, and homes," Young stated.
The California Coastline Survey, a state-funded initiative, has surveyed the state's entire coast multiple times since 2023. Researchers plan additional surveys in the fall of 2026 and spring of 2027 to measure coastal erosion resulting from the impending El Niño.
In response to rising sea levels, the San Diego City Council adopted its Coastal Resilience Master Plan in September 2025. Key project sites identified include La Jolla Shores, Tourmaline Surf Park, Mission Beach, Ocean Beach, and Sunset Cliffs. City spokesman Peter Kelly informed the Times of San Diego that while resilience projects at La Jolla Shores and Mission Beach are still in the conceptual design phase due to funding challenges, projects at Tourmaline, Ocean Beach, and Sunset Cliffs have progressed to the initial engineering design stage. The city is also implementing sand berms along Mission Bay and other beaches to mitigate heavy surf and reduce coastal damage.
The vulnerabilities extend along the entire coast, from North County to South Bay. At San Onofre State Beach, ongoing erosion is gradually undermining the sandstone that supports Interstate 5. In Oceanside, the area south of the harbor experiences up to 6.6 feet of beach retreat annually, necessitating extensive dredging projects by the Army Corps of Engineers, similar to the 236,590 cubic yards moved after the 2015-2016 storm season.
Coastal lagoons are also at risk of inlet blockages as strong waves deposit sand into estuaries. Fragile bluffs from Carlsbad to Del Mar are susceptible to destabilization when heavy rainfall coincides with wave action. "Any homes on the cliffs are going to be in danger this year," said Lisa Chaddock, a physical science professor at San Diego City College, speaking to the Times of San Diego. Chaddock also noted that heavy rainfall and rising sea levels could exacerbate South Bay's sewage issues by spreading pollution further north.