NEW ORLEANS - Isaac is losing some of its strength and has been downgraded to a tropical storm as it trudges inland over Louisiana.
Isaac has top sustained winds of 70 mph, just below the hurricane threshold of 74 mph. The storm is about 50 miles west-southwest of New Orleans, where it is bringing drenching rains and fierce winds.
City officials are imposing a dusk-to-dawn curfew in New Orleans beginning Wednesday because of the downed power lines and generally unsafe conditions.
Forecasters are warning there are still life-threatening hazards from the storm surge and inland flooding.
Earlier Wednesday Isaac pounded Louisiana with heavy rains and damaging winds Wednesday as forecasters said the biggest threat was storm-surge flooding from central Louisiana to the Florida Panhandle.
Isaac maintained Category 1 hurricane strength for hours, but just barely, with sustained winds of 75 mph, the National Hurricane Center reported. It was located directly over Houma, La., which is about 45 miles southwest of New Orleans.
The storm was crawling to the northwest at just 6 mph. It is expected to weaken to a tropical storm later Wednesday.
One of the worst hit areas was Plaquemines Parish, about 50 miles southeast of New Orleans, where water spilled over a levee. One of the highest storm-surge levels recorded so far was the 12-foot surge there late Tuesday that also flooded area homes.
"If this is a Category 1 storm, I don't want to go through anything else stronger," Plaquemines Parish President Billy Nungesser said.
Isaac passed directly over the region of marshland, fishing towns and marinas, peeling off roofs and flooding some areas.
The northern part of the parish is ringed in by the area's hurricane protection system of fortified levees and floodwalls. But stretches of it on the east bank of the Mississippi River and farther south lie outside the protection system, making it vulnerable to storm surge and flooding, Parish Councilman Kirk Lepine said.
Isaac came up the western edge of the parish, lashing at the area with powerful winds and storm surge, Lepine said.
"It came in at the worse scenario we can imagine," he said. "There's nowhere for that water to go than here."
Rescue efforts were focused Wednesday in the small enclave of Braithwaite, on the east bank of the Mississippi River in Plaquemines Parish. Sheriff deputies there were conducting rescue missions of residents trapped in homes as flooding from Isaac overtook the area, said trooper Melissa Matey, a Louisiana State Police spokeswoman.
Braithwaite was under a mandatory evacuation order before Isaac hit the Gulf, but some residents chose to stay, she said.
Early Wednesday, state police troopers were escorting National Guard troops with high-water vehicles down to that area to help in rescue efforts, state police spokesman Capt. Doug Cain said. Many of the roads in the area had become impassable.
Flanked by marshes and water, low-lying Plaquemines Parish has been repeatedly hit by disasters - from Katrina to Gustav to the 2010 BP oil spill, Cain said. Isaac late Tuesday passed directly over the area, pummeling the parish with powerful winds and a strong storm surge.
"The geography of it makes it vulnerable," Cain said. "But talk about a resilient people. They've been through this before, and they're going to make it through this one."
Isaac forced the closures of major roadways throughout the area, including U.S. 90 at the Jefferson Parish/St. Charles Parish line, the causeway over Lake Pontchartrain and LA-73 south of Plaquemines, he said.
Besides dealing with downed trees across roadways from New Orleans to Baton Rouge, state police also encountered residents who may have underestimated the storm, he said. Troopers kept busy throughout the night with highway accidents, broken down cars and several DWI arrests.
"People aren't adhering to the warnings," Cain said. "Today, we're really encouraging people to shelter in place."
The Federal Emergency Management Agency has staged supplies throughout the south in Mississippi, Alabama, Georgia, Florida, Arkansas and South Carolina. At Mississippi's Camp Shelby, the agency has 54 generators and 256,000 ready-to-eat meals. At Maxwell Air Force Base in Alabama, FEMA has 1.2 million meals, 2,134 cots and 3,800 tarps.
Volunteer organizations such as the American Red Cross and the Salvation Army can provide 65,000 hot meals a day in Louisiana, FEMA said in its daily briefing report.
So far, 350 miles of levees and floodwalls surrounding and meandering through New Orleans were holding back storm surge water as designed early Wednesday, city spokesman Hayne Rainey said. The city had not received any reports of levee breaches or calls for rescues, he said.
The Lake Borgne surge barrier, a $1 billion massive structure in the eastern part of the city erected after Katrina, stopped a 15-foot storm surge from Isaac headed to the Lower 9th Ward and other parts of the city, said Bob Turner, regional director of the Southeast Louisiana Flood Protection Authority-East, a quasi-state agency created after Katrina to monitor levee improvements. Without that 26-foot-high barrier, storm water would have overtopped levees and flooded neighborhoods ravaged by floods during Katrina, he said.
"You would have had water flowing in the Lower 9th Ward again," Turner said. "The barrier did its job."
Isaac dumped around 8 inches of rain on New Orleans the past 24 hours, seriously taxing the city's drainage pumps, which are able to pump out about 1 inch an hour, he said. That has led to some street flooding but no structure flooding had been reported, he said.
Early reports from Isaac's effects were far different from the events that unfolded around Hurricane Katrina- which slammed the region seven years to the day and led to levee breaches and mass flooding of the city. The U.S. Army Corps of Engineers rebuilt the levee and floodwall system in the New Orleans area to be much stronger at a cost of $14 billion.
The storm landed at 3:15 a.m. ET just west of Port Fourchon, about 60 miles south-southwest of New Orleans, said the National Hurricane Center.
Isaac, upgraded from a tropical storm to a Category 1 hurricane midday Tuesday, first touched land in Plaquemines Parish, about 90 miles southeast of New Orleans on Tuesday evening before heading back over the Gulf of Mexico.
Because it is moving so slowly, the storm system could dump up to 20 inches of rain in some areas. The hurricane center said Mississippi and southeastern Louisiana could see peak surges of 12 feet.
In New Orleans, streets were flooding and up to 85% of residents were without power, Mayor Mitch Landrieu said.
"One of the great challenges with this storm ... is that it's going so slowly ... which means that it's going to hover over us," he told the Weather Channel on Wednesday morning. "The longer the rain and the greater the wind ... (that) continues to concern us. That wind is really, really heavy, which is why it's important you stay inside."
"We're asking people to be patient," he said.
New Orleans, devastated by Katrina seven years ago to the day, was reporting 60-mph winds and drenching rains. Landrieu said about 1,000 National Guard troops are positioned in the city, working with police, firefighters and standing by for rescue operations.
The historic French Quarter that forms the heart of New Orleans' tourism industry appeared to have dodged the worst of Isaac. Downed tree limbs, minor flooding at intersections and a brief electrical outage overnight were the main problems confronting the residents who stayed , and stayed mostly indoors.
"Honestly, man, it's just been rain," said Huggington "Huggy" Behr, manager of Flanagan's Pub on St. Phillips, which stayed open through the night and served "about a dozen" patrons. "To us, we've seen the worst, so it's business as usual."
More than half a million Louisiana homes and businesses lost power during Isaac and most will stay that way for at least several days, Entergy spokesman Chanel Lagarde said.
As of noon Wednesday, 552,000 customers were without electricity, including 85% of New Orleans, Lagarde said.
Entergy, which serves most of Louisiana, initially planned to dispatch 4,000 workers to repair the power lines once the storm passed. But with outages so widespread, the company said it will need 10,000 workers. Crews from power companies in 24 states, through mutual aid agreements, will pitch in, he said.
"The one thing that's really hampering us is that the winds are still here. The storm is just hanging around," Lagarde said. "Looks like it won't be until tomorrow (Thursday) that we can get out there."
Workers cannot go up in bucket trucks to do repairs until the winds drop below 30 mph.
Entergy expects it will take "several days" before the company can restore power to most of its customers. The company will not have a more accurate estimate until the storm subsides and workers can assess the damage, Lagarde said.
Lagarde also said the number of outages will continue to rise as the storm travels north through the state.
Southern Mississippi was still feeling the effects of the storm but emergency management officials along the coast said they got through the night relatively unharmed.
No injuries or deaths were reported overnight in the coastal counties of Hancock or Harrison, which were two of the hardest hit by Hurricane Katrina seven years ago.
The biggest worry overnight from Hurricane Isaac?
"We're in the process of picking two people up who got stranded by the water and they're scared," Hancock County Emergency Management Director Brian Adam said Wednesday morning.
With sustained winds throughout the region topping out at about 40 mph, the main concern remains flooding from a constantly driving storm surge and what is expected to be prolonged rainfall for several days.
In Harrison County, the rising waters knocked a boat off its moorings. County Emergency Management Director Rupert Lacy said the boat slammed into Popps Ferry Bridge, forcing officials to shut it down until crews can inspect the integrity of the bridge. The bridge is one of two connecting Biloxi from the mainland, but Lacy said it could be a long time before an inspection can be done.
"We cautioned our public safety employees ... that you don't need to be out there if the winds are too high," Lacy said.
Mississippi Gov. Phil Bryant took a tour of coastal Mississippi early Wednesday and said the flooding was extensive. He told WLOX-TV that he had spoken with President Obama and requested an expedited major disaster declaration to begin the next phase of the storm response.
"We are transitioning into ... our recovery portion," Bryant told the TV station.
The Mississippi Emergency Management Agency reported that 24,400 homes were without power.
Coastal Alabama was spared major damage from Isaac, according to officials in Gulf Shores and Orange Beach.
"Structurally, we're doing very well," said Gulf Shores spokesman Grant Brown. "A couple of homes had done vinyl siding pulled off, and a little piece of sheet metal was torn off one roof. We have some water under some lower condominium areas, but no water is in buildings, as far as we can tell."
The berm along the beach held, with one small breach. High tide in this area is expected around late morning and officials are anticipating 3- to 4-foot storm surges. That could cause some additional flooding of roads in low-lying areas, Brown said.
"All in all, we fared extremely well, with virtually no damage to speak of," he said. "We anticipate tomorrow to be a cleanup day, with business as usual Friday, Saturday and Sunday."
In Orange Beach, the storm demolished a number of boat piers and docks but caused little damage to homes, said city Administrator Ken Grimes. Some homes lost power overnight but it had been restored this morning, he said.
The city's public beaches were open, although no swimming was allowed.
"We really did well," Mayor Tony Kennon said. "We had minimal flooding in the usual areas. We were fortunate that we were spared. Our hearts go out to the people of Mississippi and Louisiana that are having to deal with it."
Traffic and other activity was picking up. Businesses were reopening under cloudy skies with rain off and on and occasional gusts of wind.
"By tomorrow, anyone that comes into town almost wouldn't even know something had happened here other than a major thunderstorm," Grimes said.
As Isaac's outer bands began bending trees and lashing rain across the city, those who chose to stay were battening down homes, picking up supplies and sneaking in last-minute trips to local bars.
Melba Leggett-Barnes, who stayed in her home in the Lower 9th Ward, an area leveled during Katrina, said she felt more secure than she did seven years ago.
"I have a hurricane house this time," said Barnes, who has been living in her newly rebuilt since 2008. She and her husband, Baxter Barnes, were among the first to get a home through Brad Pitt's Make It Right program.
Her yellow house with a large porch and iron trellis was taking a beating, but holding strong. "I don't have power, but I'm all right," said Barnes, 56, a cafeteria worker for the New Orleans school system.
In other low-lying neighborhoods near rising Lake Pontchartrain, many homes were empty by Tuesday afternoon. Some residents who remained showed little fear of the approaching hurricane.
Dean Marshall, 49, stepped into Seminole Grocery for cigarettes and beer, then returned to his apartment. Marshall said he has endured many storms and is confident flood protections installed since Katrina devastated the city would hold back the water this time. "I'm not worried at all," he said. "We're going to ride it out."
Scores of fliers weren't coming in, or leaving. Flights to and from New Orleans were canceled Tuesday, and United and Southwest said operations would be halted until Thursday. Already, more than 1,300 cancellations have been reported in Florida. That number could approach 2,000 once the New Orleans and northern Gulf Coast disruptions are factored in. Most airlines have waived fees for rebooking flights canceled because of Isaac.
Search-and-rescue teams - including 48 boat teams deployed to areas prone to flooding and in direct path of the storm - have been mobilized, and Louisiana officials have asked teams from Texas and six other states to be on standby. Power crews, linemen and tree-trimmers are ready to restore power as quickly as possible if there are outages. Damage assessments, including aerial surveillance, could begin as early as Friday, Jindal said.
Louisiana has mobilized 40 "pods" in the southern part of the state and 20 in northern Louisiana - each designed to feed 5,000 people, Jindal said.
Across the region, schools and government offices have closed, hospitals and nursing homes have been evacuated and entire towns have been told to leave for higher ground. Tulane Medical Center in New Orleans closed outpatient services and rescheduled elective surgeries. Spokeswoman Susan Kaufmann said after evacuating patients following Katrina and closing for several months for storm repairs, "we're highly prepared and ready to go," Kaufmann said.
The Interim Louisiana State University Public Hospital in New Orleans, which normally houses about 170 patients on-site and 29 psychiatric patients at another facility, began preparing in earnest once it was clear Isaac was going to enter the Gulf of Mexico. On Tuesday morning, 500 staffers and doctors showed up, preparing for a three-day stay. Patients who were able to be discharged were sent home and off-site psychiatric patients were sent to a state facility in Pineville, La. Procedures not considered emergencies, such as elective surgeries, were canceled until Friday. The hospital is ready, partly because of lessons learned from Katrina, CEO Roxane Townsend said. "We've been hardened to be able to withstand up to a Category 4 hurricane."
Officials were concerned that residents would get complacent and decide not to evacuate or take precautions. President Obama urged Louisiana residents to follow officials' instructions regarding the approach of Isaac.
"Now is not the time to tempt fate, now is not the time to dismiss official warnings," Obama said. "You need to take this seriously."
Isaac left 24 dead in Haiti and the Dominican Republic but left little damage in the Florida Keys as it blew past. It promised a soaking but little more for Tampa, where the planned start of the Republican National Convention on Monday was pushed back because of the storm.
Isaac is the fourth hurricane of the 2012 Atlantic hurricane season, following Chris, Ernesto and Gordon. A typical season sees six hurricanes. Preseason forecasts from the National Oceanic and Atmospheric Administration called for four to eight hurricanes, while Colorado State University forecasters called for five hurricanes.
None of the other three hurricanes hit the USA, although Ernesto did make landfall in Mexico on Aug. 7.
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