NEW ORLEANS -- Isaac continued its slow march across Louisiana on Thursday as rising floodwaters forced tens of thousands of residents to evacuate and officials launched a "controlled" release of water from a storm-stressed dam along the border with Mississippi. At least one death was reported.
As evening approached on another soggy Gulf Coast day, hundreds of homes remained underwater and thousands of residents scrambled to emergency shelters. At least 500 people who had gambled on riding out the storm were rescued by helicopter or boat. About a third of the state remained without electrical power, even as the once-mammoth Isaac was downgraded late Thursday to a tropical depression.
Although levees protecting New Orleans held fast, sparing the city significant flooding, officials warned that the danger had not passed. Mayor Mitchell Landrieu lifted a dusk-to-dawn curfew but implored residents not to leave their homes on irresponsible sightseeing trips.
"We've got people going
block by block to assess water levels, but this storm has merely entered a different phase. It's still dangerous. The game is not over until it's over," he said.
The rains and winds eased Thursday, but rural and suburban areas remained firmly in Isaac's watery grip. Rivers across Louisiana continued to rise and many were predicted to reach historic flood levels of 20 feet or more before receding. In some places, entire communities were evacuated, including Kentwood, La., with a population of 2,200.
In a region familiar with nature's mayhem, survivors of past storm systems with names like Gustav, Ike and Katrina kept one eye on the sky and the other on rising waters, as meandering and unpredictable Isaac dumped as much as 16 inches of rain in some places. Downed trees and power lines continued to block roadways, and cars and trucks plunged headlong into standing water.
Each of southern Louisiana's numerous parishes, or counties, faced its own misery. For some, tornado watches loomed throughout the day. And in storm-thrashed Plaquemines Parish, officials began work on a levy breach to prevent the structure's failure. Meanwhile, people tried not to panic: A long line of cars snaked down nearby Belle Chasse highway for the one open gas station. Police cars patrolled grocery store parking lots, apparently to deter looters.
But the day's most tense drama occurred 60 miles northwest of New Orleans, where the Lake Tangipahoa dam -- located just across the Mississippi border -- showed signs of weakening.
Officials ordered 60,000 residents within half a mile of the swelling Tangipahoa River to evacuate as crews with backhoes, bulldozers, pumps and other equipment rushed to the 2,300-foot-long earthen dam at Percy Quinn State Park. As workers conducted the "controlled breach," a Louisiana National Guard helicopter hovered overhead, providing a minute-by-minute update of the dam's condition.
"You can see the water spilling over," Louisiana Gov. Bobby Jindal said at an afternoon briefing after a flyover of the dam, adding that officials did not think the dam had been compromised.
"Even if they declare the operation a success, I would still stay evacuated because if there is a breach, we do not want people evacuating in the middle of the night," Jindal said. "Go ahead and get out now before the water comes. That's a lot better than having to be rescued."
Mississippi Gov. Phil Bryant sounded a similarly ominous tone. "It does just take a little breach to be a big problem for all of us because that water would get down south quick," he told reporters before leaving to inspect the dam.
Meanwhile, officials threw everything they could muster at Isaac. Jindal's tally included 314 National Guard troops, 300 search and rescue workers and hundreds of boats, aircraft and other vehicles.
Still, on many residential streets, storm waters defied sand bags, flooding into homes and engulfing rural roadside mail boxes. Residents without boats or Jet Skis were simply out of luck. At one flooded and abandoned home, two cows stood forlornly on a front porch surrounded by water, like two castaways marooned at sea. The skies above many communities were dotted with National Guard Black Hawk helicopters searching for residents in need of rescue.
Along the shores of Lake Pontchartrain north of New Orleans, dozens of buses and high-water vehicles helped evacuate about 3,000 people from rising waters. Even residents who were not threatened were asked to remain inside their homes, many of which remained under a boil-water advisory for drinking water.
At day's end, more than 610,000 people remained without power in Louisiana and 43,000 in Mississippi.
A 62-year-old tow truck driver, Greg Parker, was killed overnight when a tree fell on the cab of his truck in Picayune, Miss., said Tony Bounds, a spokesman for Pearl River County's emergency operations center in Poplarville, Miss.
"With one of those wind gusts, the tree came over and crushed him," he said.
As Louisiana splashed and waded its way through another furious summer storm, Thursday became a day of assessment, with officials waiting for the rains to finally stop so they could take stock of the damage.
As the brunt of Isaac's wrath moved north, officials -- especially those in New Orleans -- breathed a collective sigh of relief. In 2005, powerful Katrina came ashore as a Category 3 with 125-mph winds, while Category 1 Isaac packed 80 mph winds at landfall Tuesday evening.
Still, the storm was no Katrina. This time around, they said, the levees held firm.
"Our system has held up real well," said Susan Maclay, president of the board of directors of the Southeast Louisiana Flood Protection Authority West.