Downgraded Isaac lashes New Orleans

Tropical Storm Isaac continued to lash New Orleans with heavy rain today despite being downgraded, as residents in cars and homes were stranded exactly seven years after Hurricane Katrina devastated the city.

In the swampy bayous of rural Louisiana, rescuers in boats tried to reach people stranded there.

In New Orleans, the newly-fortified levee system appeared to be holding, though power lines were downed and debris littered the streets, prompting officials to impose a dusk-to-dawn curfew.

Louisiana officials said they may have to intentionally breach a levee in a flooded area as Isaac made a slow, drenching slog inland from the Gulf of Mexico.

Isaac has top sustained winds of 70mph (112kph), just below the hurricane threshold of 74mph (119kph). The storm is about 50 miles (80km) west-southwest of New Orleans, where it is bringing drenching rain and fierce winds.

Louisiana Governor Bobby Jindal said officials may cut a hole in a levee on the east bank of Plaquemines Parish to relieve pressure on the structure.

At a news conference in Baton Rouge, he said there was no estimate on when that might occur. He said as many as 40 people are reportedly in need of rescue in the area.

Plaquemines Parish, a rural area south of New Orleans, has also ordered a mandatory evacuation for the west bank of the Mississippi River below Belle Chasse, worried about a storm surge.

The order affects about 3,000 people in the area, including a nursing home with 112 residents. Officials said the evacuation was ordered out of concern that more storm surge from Isaac would be pushed into the area and levees might be overtopped.

Rescuers in boats and trucks plucked a handful of people who became stranded by floodwater in thinly populated areas of south-east Louisiana. Authorities feared many more could need help after a night of slashing rain and fierce winds that knocked out power to more than 600,000 households and businesses.

The hurricane also cancelled commemoration ceremonies for Katrina’s 1,800 dead in Louisiana and Mississippi today.

Isaac was testing a New Orleans levee system bolstered by 14 billion dollars in federal repairs and improvements after the catastrophic failures during Katrina.

Army Corps spokeswoman Rachel Rodi said the city’s bigger, stronger levees were withstanding the assault.

New Orleans Mayor Mitch Landrieu issued a curfew for the city as Isaac lashed the city on the seven-year anniversary of Katrina’s destructive arrival.

Police cars had been patrolling the nearly empty streets since Isaac began bringing fierce winds and heavy rain to the city last night. The curfew was set to start tonight and last until further notice.

The storm drew massive attention because of its timing – coinciding not only with the Katrina anniversary, but also the first major speeches of the Republican National Convention in Tampa, Florida.

Isaac also posed political challenges with echoes of those that followed Katrina, a reminder of how the storm became a symbol of government ineptitude.

President Barack Obama sought to demonstrate his ability to guide the nation through a natural disaster, and Republicans tried to reassure residents as they formally nominated former Massachusetts Governor Mitt Romney as their presidential candidate.

Mr Obama, campaigning before a university crowd in Virginia, pledged that the government was “doing every single thing we need to do to make sure the folks down there are taken care of”.

Although Isaac was much weaker than Katrina, the threat of dangerous storm surges and flooding from heavy rain was expected to last all day and into the night as the immense comma-shaped storm crawled across Louisiana.

The extent of the damage was not entirely clear because officials did not want to send emergency crews into harm’s way. In Plaquemines Parish, a fishing community, about two dozen people who stayed behind despite evacuation orders needed to be rescued.

As Isaac’s eye passed overhead, authorities in armoured vehicles saved a family whose roof was ripped off.

Two police officers had to be rescued by boat after their car became stuck. Rescuers were waiting for the strong winds to die down before moving out to search for other people.

Water driven by the large and powerful storm flooded over an 18-mile (30km) stretch of one levee in Plaquemines Parish. The levee, one of many across the low-lying coastal zone, is not part of the new defences constructed in New Orleans after Katrina.

Isaac came ashore at 7.45pm EDT (1145 GMT) with 80mph (130kph) winds near the mouth of the Mississippi River, driving a wall of water nearly 11ft (3.4m) high inland and soaking a neck of land that stretches into the Gulf.

The storm stalled for several hours before resuming a slow trek inland, and forecasters said that was in keeping with its erratic history. The slow motion over land means Isaac could be a major soaker, dumping up to 20in (50cm) of rain in some areas. But every system is different.

Isaac’s winds and sheets of rain whipped New Orleans, where forecasters said the city’s skyscrapers could be subject to gusts up to 100mph (160kph).

Tens of thousands of people had been told ahead of Isaac to leave low-lying areas of Mississippi and Louisiana, including 700 patients of Louisiana nursing homes. Mississippi shut down the state’s 12 shorefront casinos.

There was already simmering political fallout from the storm.

Louisiana Governor Jindal, who cancelled his trip to the convention in Tampa, said the Obama administration’s disaster declaration fell short of the federal help he had requested.

Mr Jindal said he wanted a promise from the federal government to be reimbursed for storm preparation costs.

Reporter Greg Milam is there and has said that the flooding will now become the city's main concern:

"They'll hope that it will start to break up as it reaches land that’s what normally happens having gathered heat over the sea", he said.

" But there will be much more rain to come and that worry about isolated flooding is a real concern here"