"At a normal tide on a normal day on the Southern California coast, ankle-high waves glide over a narrow strip of gold sand. On one side sits the largest body of water in the world. On the other, a row of houses with a cumulative value in the hundreds of millions of dollars, propped on water-stained stilts.
Property value ebbs and flows, but when it comes to coastal real estate "the trend lines are pretty clear," says California state Sen. Ben Allen, squinting in the sun. "And they're not pretty."
Within the span of a 30-year mortgage, more than $100 billion worth of American homes is expected to be at risk of chronic flooding. As the climate warms and oceans rise, narrow strips of sand such as the one Allen is standing on, will be submerged, leaving coastal communities — affluent and not — with the torturous question of how to adjust. Build sea walls? Dump sand? For how long and at what cost?"
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