Many U.S. beaches are washing away, being pushed into decline by erosion, coastal overdevelopment, and wrongheaded conservation efforts. Billions of dollars have been spent in the U.S. to keep beaches in place, but efforts in many cases have only exacerbated erosion. Ecologists say that for beaches to survive, they must be free to move and evolve. Meanwhile, two U.K. environmental groups say British beaches are also threatened, as concrete barriers built to keep water away from development are causing serious erosion problems, threatening habitat for a number of species.