How much to rebuild after Katrina?

The floodwaters are in retreat and urgent human needs are being met - an effort that must continue as a top priority. But attention must also shift toward confronting the long-term effects of hurricane Katrina and how best to restore the region.

The issues are difficult and complex. Hundreds of thousands of homes and businesses, as well as roads, bridges, utilities, and public buildings, have been damaged or destroyed. Rebuilding estimates top $100 billion and may rise much higher, making Katrina the most costly natural disaster in US history. Questions about what to rebuild, where to rebuild, how to rebuild - and who will pay the bills - will be wrestled over for years to come.

Just as Sept. 11 roused the country out of complacency about a new style of security threat, Katrina has blown in to remind Americans they cannot entirely tame the natural world. Some forecasters see a pattern of severe storms developing in the years ahead, coupled with rising ocean levels, which may exacerbate the problem.

Who will absorb the costs of future disasters? Those who are unfortunate enough to be the survivors? State and local governments? All Americans? These questions loom.

So does the question of how we reduce the risk. Will Americans be willing to relook at coastal management policies and adopt new practices - such as restoring wetlands - that could mitigate storm damage? Will they be willing to forgo building in vulnerable oceanfront locations? If the nation demands more prudent coastal development on the Gulf, will residents there ask why they should sacrifice unless those in other coastal regions do as well?

By one estimate, 1 in 5 homes in Florida were damaged by a hurricane last year. Seventeen of the 20 fastest-growing counties in the US are on the ocean, including many along the Gulf and in Florida.

No one doubts that a vital New Orleans must be part of a new Gulf Coast that rises from the debris. The city's economic, historic, and cultural prominence make it irreplaceable, despite sitting like a saucer seven feet below sea level. To quote Pierce Lewis, as many have in recent days, the Big Easy is an "inevitable city on an impossible site." It appears now that most of the city's iconic buildings and tourist attractions have been spared.

But building higher and stronger levees to withstand the severest storm will be much too costly. Wetlands surrounding the city once provided a 150-mile-wide shock absorber, reducing a hurricane's storm surge with every mile. They've shrunk to just 35 miles. Likewise, the coast of Mississippi has replaced many of its wetlands with gambling casinos and other development. Ways to restore these natural barriers must be considered.

In the well-known biblical story, a wise man "built his house upon a rock: And the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell not: for it was founded upon a rock." Jesus meant the story to teach a spiritual lesson, not provide a literal building code. But it does suggest that careful thought should precede action; that prudent planning can manifest itself into communities that will withstand the storm.