NEW JERSEY'S BEACHES: On Shifting Sands.

ON STORMY DAYS, the wind at the tip of Sandy Hook, a former military base now turned into the bustling Gateway National Recreation Area, is enough to knock you down, and it churns the Atlantic into a froth favored by surfers but anathema to the embattled homeowners on this exposed coast.

Despite ominous reports of sea level rise, and horrific damage caused by ever-increasing storms, proximity to New York City has meant rapidly escalating land values for this region, and a determination to build right to the water's edge.

Sandy Hook is like a finger pointed into the ocean towards Brooklyn, a beacon for the great New York/New Jersey estuary. The national park is a rare respite from a landscape dominated by beach communities and chock-a-block strip development. A former officer's quarters in the park, not far from 19th century coastal defense emplacements, now serves as home to two organizations that are trying to protect this prosperous region from itself. The American Littoral Society and New York/New Jersey Baykeeper work together trying to preserve what's left of a natural environment laid low by dredging, filling and construction.

Dery Bennett, the Littoral Society's friendly and grizzled director, takes visitors on a tour of nearby Sea Bright, where relatively modest vacation homes hide behind a protective seawall built in the 1930s. There is a 100-foot-wide beach behind the wall, built not over the millennia by the workings of the tides but in 1996 by the U.S. Army Corps of Engineers as part of a $9 billion plan to "replenish" the beaches along the 127-mile New Jersey shore.

The luncheonette in downtown Sea Bright displays some starkly revealing aerial photos. One, taken in the early 1990s, shows a town with no beach to speak of, thanks largely to the effects of that seawall. The other, from last year, shows a wide expanse of sand. Bennett, who points out"public access" stairways along the seawall that were erected by the Corps but lack any nearby parking, joins Baykeeper Andy Willner as a major critic of the quick fix. Not only does the massive effort to pump in sand benefit only a few wealthy homeowners, they say, but it also encourages even more dangerous shoreline development. And, they add, it's ultimately folly because global warming-induced storms and rising tides will likely wash it all away in the next decade.

Orrin Pilkey's classic book The Corps and the Shore, written with Katharine Dixon, details how jetties, seawalls, groins and other desperate maneuvers offer only temporary respite from the natural effects of erosion and shifting coastline--and ultimately make things worse. The same thing is true of imported sand. New Jersey beaches, the authors write, can expect only a one- to three-year lifespan, and there is damage to coral, water clarity and bottom-dwellers.

"There's a natural process called littoral drift," explains Willner as he provides a pickup-based tour of Sandy Hook's windswept charms. "Sand from ancient granite mountains like the Appalachians was carried down by glacial action to create the beaches. Once here, it moves north in a predictable, inexorable fashion, reshaping the coast as it goes. What you see today is the result of millions of years of geological evolution, but people expect that process to stop when human infrastructure is introduced. They're putting homes and beach clubs on mobile land. And they;re taking a crapshoot that those natural processes won't happen in their lifetimes. When it does, they're always surprised."

The speed with which the ocean reclaims its own is exacerbated by rising tides. According to Norbert Psuty, a coastal geomorphologist with the Department of Marine and Coastal Sciences at Rutgers University, deeper in-shore waters means more powerful waves, which move more quickly and retain more energy. In the last 100 years, the New Jersey coast has sunk 16 inches, through a combination of tectonic plate depression and sea level rise. "Almost everything we have along the coast is at risk sooner or later," says Psuty. "We've been fortunate not to have taken any direct hits lately." Stephen Leatherman, who directs the Hurricane Center at Florida International University, puts it another way: "The erosion rates are going to accelerate in the future, which means the cost is going to go up exponentially to maintain these beaches. And no one seems to have figured it out yet. It's like a great big secret."

There are no easy answers on the Jersey shore. According to the Philadelphia Inquirer, property that was worth $8.7 billion in 1962 is now worth $34.3 billion when adjusted for inflation. In 1945, George Lippincott bought a house with 1.2 acres in coastal Avalon for $500, raising the money by selling a single rare stamp. This year, Lippincott's descendants put the property on the market for $3.5 million. The coast is now fully developed, with the result that a "100-year storm" would be far more devastating today than it would have been 50 years ago. Taxpayers will foot much of the bill for any rebuilding, since flood insurance is federally guaranteed.

Tourism brings in $12 billion annually to the New Jersey shore. In Sandy Hook, Dery Bennett's stand against beach replenishment has put him at odds with the business community, which sees the sand as vital to its busy tourist season. Real estate lobbyist Ken Smith calls Bennett "a lousy misanthrope" for opposing more coastal development, and Bennett returns the volley by labeling Smith "a shill for the real estate industry." Is agreement likely in the face of such polarization?

Climate scientists predict that sea level in New Jersey could rise an additional two feet in the next 100 years, with predictable havoc wrought on that priceless real estate. Chances are, people will retreat to higher ground, but then come back to rebuild with federal help. But the time is fast approaching when we may have to abandon all those beautiful homes, beach clubs and resort hotels, because they're built on rapidly shifting sands. CONTACT: American Littoral Society, [phone], www.alsnyc.org; New York/New Jersey Baykeeper, [phone], www.nynjbaykeeper.org.

JIM MOTAVALLI is editor of E and author of Forward Drive: The Race to Build "Clean" Cars for the Future (Sierra Club Books/Random House).