Will the levees hold?

NEW ORLEANS - Hurricane Gustav churned toward a projected landfall along the Louisiana coast today as leaders of this hurricane-weary city pleaded for residents to flee and imposed a dusk-to-dawn curfew on those remaining.

Tens of thousands of residents escaped New Orleans and Gulf Coast towns in Louisiana and Mississippi as the storm approached. Late Sunday, Louisiana Gov. Bobby Jindal issued one last plea to the roughly 100,000 Louisianans still left on the coast: "If you've not evacuated, please do so. There are still a few hours left."

Forecasters said Gustav would probably roar ashore south and west of New Orleans sometime this morning as a Category 3 storm, packing winds of at least 111 miles per hour. Hurricane warnings were posted from the Louisiana-Texas state line all the way to the Florida panhandle.

"I lost everything in Katrina and it looks like I might lose it all again," said Deloris Blanche, 65, who waited to board one of the last buses in New Orleans taking evacuees to safer points inland.

The city appeared largely deserted, almost ghostly, on Sunday with the famous French Quarter empty and buildings boarded up. Police cars with blue lights flashing and armed National Guardsmen stationed on corners outnumbered pedestrians.

Grave concerns remained over whether the city's patched-up levee system would withstand Gustav's storm surge -- projected to be 14 feet -- or instead might give way and flood the city for the second time in three years.

"We worry about the surge over-topping the levees, and then we worry about rain," said Mayor Ray Nagin, noting that the city's pumping system might be overwhelmed.

Asked which levees stood the greatest chance of failing, Louisiana Lt. Gov. Mitch Landrieu said: "All of them."

The U.S. Army Corps of Engineers has worked since 2005 to repair and reinforce 325 miles of levees and flood walls that ring New Orleans and its neighboring parishes, but experts said the project is only 20 percent complete and the $15 billion in improvements won't be finished until 2011. Even when finished, the work still won't create levees that can withstand a Katrina-intensity storm, which Gustav is projected to be at landfall.

In his comments, Nagin also warned that residents choosing to remain in New Orleans would get no immediate help if the floodwaters rise and that heavy patrols by police and the National Guard would deal firmly with any looters.

"Looting will not be tolerated," he said, announcing that a dawn-to-dusk curfew would be strictly enforced. "Looters will go directly to jail. You will not get a pass this time."

New Orleans descended into chaos after Hurricane Katrina in 2005, with looters smashing shop windows and hauling off goods even as desperate people clung to their rooftops and waited days to be rescued from flooded portions of the city.

As the storm moved toward the Gulf Coast, the oil industry shut down nearly all offshore platforms and many refineries as Gustav approached, raising the specter of higher fuel prices in days and weeks ahead.

President Bush, who canceled plans to speak at the Republican National Convention in St. Paul, will instead fly to Texas today to meet with emergency officials. He also planned to visit Louisiana as soon as conditions permit, the White House said.

"The Army Corps of Engineers informs me that while the levees are stronger than they've ever been, people across the Gulf Coast, especially in New Orleans, need to understand that in a storm of this size there is serious risk of significant flooding," Bush said Sunday after being briefed by federal emergency managers.

Bush was blistered with criticism for his administration's lackluster response after Hurricane Katrina struck the Gulf Coast and flooded New Orleans in 2005, killing more than 1,600 people.

Homeland Security Secretary Michael Chertoff was also flying to the region and planned to remain there during the storm.

With memories of Katrina still fresh, residents appeared to be heeding the calls to evacuate for Gustav. Louisiana police officials estimated that 90 percent of the state's coastal population had evacuated by Sunday night.

Traffic on highways leading out of the city inched along, although a system in which cars were allowed to flee on lanes normally used for in-bound traffic appeared to be working well.

Those without means to escape on their own were being taken out by bus and train. In New Orleans, city officials said they had successfully evacuated more than 18,000 infirm or impoverished residents who needed help to leave, giving them confidence that there would be no repeat of the human disaster that followed Hurricane Katrina, when tens of thousands of residents were left stranded by the failure of the city's levees.

Officials backed away from earlier estimates that up to 30,000 residents might need help to evacuate and said they felt they had reached everyone who required assistance. But some community activists, while generally praising the city's evacuation efforts, expressed fears that mentally troubled residents might have been left behind.

Even in the city's higher elevations along the east bank of the Mississippi River -- an area that remained dry during Katrina -- most homes and streets appeared empty.

A few stragglers lashed items on the roofs of their cars in the Garden District, while a lone jogger plodded down St. Charles Avenue, running along the tracks of the city's famous streetcar line.

"I wish it was this peaceful and safe all the time," said Butler Ives, 36, who was busy securing a Garden District house he shares with a friend and planned to stay. "We've got wine, we've got cigars and we've got guns," a reference to the fear of looting.

Forecasters late Sunday predicted Gustav would be a Category 3 storm at landfall, meaning it would be capable of widespread damage, but short of earlier predictions that it could reach the top of the five-stage Saffir-Simpson scale of hurricane intensity. The storm blossomed to 150 mph over the weekend as it crossed warm waters south of Cuba, but then lost power after passing over the island.

Forecasters said it might jog a bit west just before landfall, which might ease the blow to New Orleans, but worries over the storm surge remained.

Surge models suggest larger areas of southeast Louisiana, including parts of the greater New Orleans area, could be flooded by several feet of water. Gustav appears most likely to overwhelm the levees west of the city.

The Associated Press, Los Angeles Times and Chicago Tribune contributed to this report.