NEW ORLEANS (CN) - With 85 percent of the city without power, New Orleans declared a dusk-to-dawn curfew to deter looters Wednesday, and Baton Rouge followed suit.
Floods closed roads throughout the state, and officials said the 6 p.m. to 6 a.m. curfew also would protect people from fallen power lines and trees.
New Orleans Mayor Mitch Landrieu told Reuters that his city's restored, multibillion-dollar levee system worked "exactly as it should."
But Interstate 10 was closed by flooding Wednesday morning at LaPlace, about 25 miles west of New Orleans, and a LaPlace subdivision was inundated by a tidal surge off Lake Pontchartrain.
Residents of St. James Parish said most of the parish was covered in water Wednesday, as the water came off the lake fast. Water was 4 feet deep in some homes. Others recounted wading through waist-high and even neck-high water to seek shelter.
A parish is Louisiana's equivalent to a county.
It was an unexpected flood for residents of LaPlace. Parish officials said neighboring parishes had higher floodwalls.
"New Orleans has a wall. Jefferson has a wall. St. Charles has a wall. We don't have a wall," St. John Parish Councilman Lucien Gauff III told local news.
Officials plan to cut a hole in a levee today (Thursday) to relieve some of the flooding in Plaquemines Parish, along an 18-mile stretch of locally managed levee that was breached when Hurricane Isaac made landfall there late Tuesday night.
Gov. Bobby Jindal said about 800 homes were flooded by the levee breach. Dozens of people trapped in the rising water were rescued Wednesday by the National Guard.
State officials reversed the pumps at a freshwater diversion project Wednesday to drain the flooded area along the levee back into the Mississippi River. Reversing the pumps reduced the water level from about 14 feet to 7 feet, a hole will be cut in the levee to drain the rest of the water in a few days rather than the three weeks or more it might take for waters to go down.
National Guard troops evacuated about 3,000 other residents from the west bank of Plaquemines Parish, just south of Belle Chasse.
In the coastal town of Lafitte, rising waters were too deep Wednesday evening for Jefferson Parish's high-water rescue vehicles to evacuate residents who remained.
"This is the first time this has happened of all the times we have used these trucks since Katrina," Jefferson Parish Sheriff Newell Normand told local news.
Earlier Wednesday, parish officials warned residents that time was running out to evacuate the coastal communities of Lafitte, Barataria and Crown Point.
Isaac was downgraded from a hurricane to a tropical storm Wednesday afternoon. Officials warned that the drop in wind from the 74 mph that made it a hurricane to just 70 mph would not significantly weaken the storm's force.
Isaac's center crawled through Baton Rouge late Wednesday night at a snail speed of about 6 mph.
Baton Rouge officials expect that Isaac's slow pace and torrential rain will put its damage on par with Hurricane Gustav in 2008, which at the time was the worst storm ever to sweep through the capital city.
Restoring power to nearly 600,000 homes statewide could take days. First, winds need to subside and high waters recede, then rubbish from the storm, including downed tree limbs, will have to be cleared away.
Gov. Jindal estimated that Isaac had cost the state more than $24 million by Wednesday.Follow @https://twitter.com/sabrinacanfiel2
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