Updated at 12:10 p.m. ET
(CBS/AP) NEW ORLEANS - New Orleans' newly fortified flood protection system was holding up to powerful wind gusts and sheets of rain from Hurricane Isaac after the storm earlier pushed water over a rural levee in southern Louisiana, officials said seven years to the day after Hurricane Katrina.
Isaac's gusts reached more than 60 miles per hour, flooding some homes, knocking out power and immersing beach-front roads in Louisiana and Mississippi early Wednesday as it began a drenching slog inland from the Gulf of Mexico.
Army Corps of Engineers spokeswoman Rachel Rodi said the group expected to be on "high alert" for the next 12 to 24 hours, but they're confident it's going well so far. She said a pumping station at the 17th Street canal -- which was built at the site of a levee that breached during Katrina -- briefly went down early Wednesday, but operators were able to manually get it working again.
Isaac's dangerous storm surges and flooding threats from heavy rain were expected to last all day and into the night as it crawls over Louisiana, the U.S. National Hurricane Center in Miami warned.
Water driven by the large and powerful storm pushed over the top of an 18-mile stretch of one levee in Plaquemines Parish south of New Orleans, flooding some homes in a thinly populated area. The levee is one of many across the low-lying coastal zone and not part of New Orleans' defenses.
"When this is over, I think we need to check the wind speeds because I lost a good portion of my roof, my fence is down, and water is blowing through the sockets in my house from the back wall," Parish President Billy Nungesser said in a phone call to CBS New Orleans affiliate WWL-TV. "That only happened in Katrina."
Plaquemines Parish resident Gene Oddo called WWL-TV while riding out the storm with his wife and baby girl in their attic Wednesday morning in Braithwaite, La. He said the water level was up to his house's doorframe.(Watch at left)
"The water came up so quick," Oddo told WWL-TV. "It looks like we lost everything. If I have to, I may have to shoot a hole in my attic here to get out on our roof, but it looks like the water's not coming up anymore."
Oddo said authorities told him about storm surge going over the levee around 2 a.m.
"The threat was for flood, which I knew that, and I'd rather be here to save what I can because the insurance doesn't cover all that much," Oddo said.
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State officials said about two dozen people were stuck and in need of rescue on the east bank of Plaquemines Parish. Louisiana National Guard spokesman Lt. Col. Mike Kazmierzak said evacuations there are beginning. He said reports are sketchy but he's heard there are "quite a few people on a levee waiting to be rescued."
Kevin Davis, director of the Governor's Office of Homeland Security and Emergency Preparedness, said the parish's east bank has seen flooding of four to nine feet across 18 miles. He said a levee was overtopped and then breached by scouring. On the parish's west bank, Davis said there are concerns of another levee being overtopped and then scoured like the east side. That area is nine miles south of Belle Chasse, La.
"We did have two parish police officers that were stuck in a car there. We just found out they were rescued and are safe," said emergency management spokeswoman Caitlin Campbell. Two other parish workers in a boat rescued them.
CBS News hurricane consultant David Bernard reports that the storm is moving northwest across Louisiana at 6 mph, keeping its 80 mph winds moving slowly across the state all day Wednesday. Isaac's path is expected to take it to central Louisiana by late Wednesday or early Thursday.
WFOR Miami's interactive storm tracker
In Houma, La., about 60 miles southwest of New Orleans, CBS News correspondent Manuel Bojorquez reports that Isaac's slower ground speed dumps more rain while leaving locals and cleanup crews at a standstill with no clear sign of when the storm will clear up or clear out. Bernard reports that areas at Isaac's center may see as many as 15 inches of rain Wednesday.
In Gulfport, Miss., CBS News correspondent Mark Strassmann reports Isaac has made many roads unsuitable for driving. Floodwaters prevented firefighters from reaching a house fire in Bay St. Louis, Miss. By the time they arrived, by boat, the vacant house had burned down to the stilts.
The National Weather Service issued a tornado warning late Wednesday morning for the area in Mississippi including Gulfport and the neighboring Gulf Coast city of Long Beach.
As the rain continued and winds pushed across the Gulf Coast, it remained far too soon to determine the full extent of the damage.
Isaac was packing 80 mph winds, making it a Category 1 hurricane. It came ashore at 7:45 p.m. EDT Tuesday near the mouth of the Mississippi River, driving a wall of water nearly 11 feet high 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 the its erratic history.
Isaac's winds and sheets of rain whipped New Orleans, where forecasters said the city's skyscrapers could feel gusts up to 100 mph. The National Weather Service said more than 9 inches of rain had fallen in New Orleans in the 24 hours up to 7 a.m.
