Unsafe Harbor

Hurricanes Rita and Katrina will both be remembered for their crowded human calamities: the gridlocked escape from Houston, the suffering at the Superdome. But in dozens of small towns dug into the fragile ecosystems of the coastal marshes, far from the urban meltdowns, communities weren't just inflamed, they were annihilated. In Cameron Parish, La., along the border with Texas, Rita washed towns like Creole, Oak Grove and Grand Chenier into the sea. In neighboring Vermilion Parish, the residents of Pecan Island returned to find little more than a mile-wide debris field choked with dead marsh grasses.

In south Plaquemines Parish, a sinuous ribbon of land between the Mississippi River and the Gulf of Mexico, not only were all the towns lost to Katrina's fury, but nature itself seems mortally wounded as well. The 30-mile strip of houses, farms and schools has been transformed into a sump filled with fetid water. Groves of orange trees lie half submerged near Triumph. In Empire, almost 1 million gallons of oil have broken out of a giant Chevron storage tank, coating the levees and seeping into the marshland. A herd of cows staggers ankle deep through greasy waters in Venice. A few miles north, horses graze amid dead fish and the hulks of beached shrimp trawlers.

Devastation that complete looks like an act of God, but residents here know that the truth is more complicated. For decades the oil-rig roughnecks and menhaden fishermen who have made their living on this fragile shore have seen drilling and dredging kill off the surrounding marshes and forests, leaving them defenseless against the rising waters. "Our parish was not only destroyed by nature," says Benny Rousselle, Plaquemines Parish president. "It was destroyed by man."

Katrina was less an isolated episode than a cruel salvo in a continuing war being waged across much of the U.S. Americans are now predominantly a coastal people, drawn to the shores for work and play. Yet their presence at the water's edge threatens the natural barriers that should be shielding them. In Louisiana, the Mississippi River has been lashed into tenuous submission, its absorbent delta constricted and carved into channels for oil pipelines and navigation routes. In Alabama and Mississippi, the playground of the Gulf Coast has been developed to the edge of the open water, rebuilt bigger and more audaciously after each storm that wipes it out.

Rita's eye took dead aim at the already debilitated Sabine Basin, which lies between Port Arthur, Texas, and Lake

Charles, La. Since 1930, coastal erosion and channel dredging have destroyed a third of the marshlands that once formed a bulwark between those cities and the Gulf. In some respects, the coast's best defenses were scuttled before the battle with Rita was even joined.

In Louisiana the cleanup of the two-part disaster is just getting started. But many of the state's best engineering and environmental minds are already looking much further down the road, at what it will take to safely maintain humankind's precarious foothold at the water's edge. Louisiana's coastal towns have vowed to rebuild, but will they ever truly be safe?