Land: Losing Ground

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When Byron L. Ramsing returns this summer to Martha's Vineyard, he is in for a rude surprise. His Chilmark house, which used to be a safe 200 ft. from the cliffs overlooking the sea, is now only 80 ft. away, and the broad stone steps that were once in his backyard are now on the beach below. On the New Jersey shore, the sea has slowly devoured 50 square blocks of the town of Cape May Point, and St. Peter's by the Sea Episcopal Church, a frame structure which has already been moved three times, now has the sea only 50 ft. from its doorstep. Parts of North Carolina's storm-crossed Outer Banks are dissolving into the Atlantic at the rate of 15 ft. a year. There is literally no beach left in parts of Miami Beach; the ocean is lapping at the sea walls, even threatens to topple a brand-new high-rise-apartment complex appropriately named Harbor House.

Surely, but not necessarily slowly, U.S. shore lines are receding, and the oceans are advancing upon the land. According to the Army Corps of Engineers, at least 90% of the Atlantic Coast from New Hampshire to Florida is being eroded, and a dozen of the biggest public beaches are so badly depleted that they are in danger of being carried away. And the Gulf Coast and the Pacific are not much better off.

Worse & Worse. The problem lies in the fact that a beach is a moving thing, alternately yielding and receiving sand from the action of tides and waves.

Along the so-called "high energy" beaches, where the water is turbulent and the currents swift, the offshore sand level can rise and fall as much as 4 ft. in half a day. Most beaches are subject to extremely heavy erosion during winter storms, then are rebuilt by sand-bearing currents during the summer. But, says Joseph Caldwell, head of the Beach Erosion Board of the Army Corps of Engineers, "the beaches generally wash out more each winter than they get built back each summer."

Often, the residents of the beach are not even aware that it is in danger. "The people kid themselves," Caldwell says.

"They want to see a bigger beach so much that they imagine it really is bigger. The thing that finally takes a beach apart is usually a terrible storm, but in the preceding years there has been gradual erosion. It keeps sneaking up and gets worse and worse."

Plastic Seaweed. As usual, man has contributed his share to the process of erosion. He has lined the beaches with hotels, apartments and roads, leveled the high dunes that blocked his view, thus stripping them of their protective grasses. Navigational jetties, jutting into the sea to protect shipping at river mouths, and man-made inlets change the pattern of offshore currents and block the littoral flow of sand to downdrift beaches, literally starving them out. There is no easy way to combat erosion. All along the Atlantic, communities have lined their beaches with "groins" (short jetties) in hopes of trapping the sand before it can be carried away. But the groins are only partly effective, and, like the navigational jetties, they also keep sand away from the beaches. Florida, despite prevalent use of groins, is still losing 20 million cu. yds. of sand each year.