Can a California town move back from the sea?

Broadly speaking, though, those practical things are limited. According to the San Francisco Bay Area Planning and Urban Research Association, or SPUR, a city can undertake one of several strategies: Build a barrier, armor the coast with levees and seawalls, elevate land, create “living shorelines” to absorb flooding and slow erosion, or retreat. This last strategy, “managed retreat,” SPUR warns, “is a political quagmire. It involves tremendous legal and equity issues, because not all property owners are willing sellers. And in many places, shoreline communities are already disadvantaged and lack the adaptive capacity to relocate.” It is into this quagmire that Dedina has decided to wade.Other cities have proven unwilling to take on the idea of managed retreat, mostly because the very mention of it can tank real estate prices. Besides, there are alternatives. A favorite in California is sand replenishment, where sand is added to a beach as a buffer against rising tides, erosion and other natural forces. Six years ago, Imperial Beach added 300,000 cubic yards of large-grain sand across four miles of beachfront. But the practice has many critics: Waves, tides and currents can wash the sand away, and what remains can damage or destroy ecosystems. Surfers hate it because it alters breaks — and, indeed, Imperial Beach has seen fewer surfers since it added sand. “Sand replenishment is lame,” a surfer named Brian Valdez told me when I caught up with him after a morning session. “But I bet it’ll be impossible to find a California beach without it in the future.” Dedina does not see a future in sand. His city, he believes, will have to do what was once unthinkable: It will have to retreat. Managed retreat represents a planned move away from the coast, allowing the beach to erode for the forces of nature to take over. This, of course, is a gargantuan task. How does a city take all the homes and businesses along its coast and relocate them inland? It has never been done in the Western U.S. before, certainly not on the scale that would be needed — even for a city as small as Imperial Beach.