Rescue workers transport residents trapped by rising water from Tropical Storm Isaac in LaPlace, Louisiana, on Wednesday, August 29. While Isaac lost its hurricane status, officials warned of continued threats from storm surges and flooding. 
Henry Cox talks with stranded residents in LaPlace. 
Errol Ragas walks past a cemetery to recover dry blankets from his home in Oakville, Louisiana. 
Storm-weary residents take refuge at a high school gymnasium in Belle Chasse, a low-lying area outside of New Orleans. 
St. John Parish Sherriff officials rescue local residents from the flood waters in LaPlace. 
Lisa, Christopher and Leroy Smith sit in a boat after being pulled from the flood waters. 
A stop sign stands askew in New Orleans after being blown by Isaac. 
People gather at a bar in the French Quarter during ongoing rain from Isaac. The area appeared largely unscathed by the storm. 
A house in New Orleans collapsed during the height of Hurricane Isaac, destroying three vehicles parked alongside it Wednesday. 
Waves from Hurricane Isaac pummel Ken Combs Pier in Gulfport, Mississippi. 
A street sign turned upside down, likely the result of bricks falling overnight from a building along the deserted streets of New Orleans. 
Errol Ragas walks past a cemetery to recover dry blankets from his home as rising waters flood his neighborhood in Plaquemines Parish, Louisiana. The parish, south of New Orleans, was the area most heavily damaged by the hurricane. 
A car sits submerged in the flood waters in LaPlace, Louisiana. 
People gather beneath an awning for an impromptu cookout at a bar that lost electricity during Hurricane Isaac in New Orleans. 
Emergency crews and residents rescue a dog during Hurricane Isaac on Highway 39 separating Plaquemines and St. Bernard parishes on Wednesday, August 29, in Louisiana. 
First responders carry people across the top of the levee from Plaquemines Parish to St. Bernard Parish. 
Mark Savoie cleans Espanade Avenue in New Orleans of tree debris to help the area near Burgundy drain as Isaac slowly moves inland. 
A worker in the driving rain tries to clear fallen limbs in the riverbound lanes of Espanade Avenue near McDonogh High School in New Orleans. 
Winds from Hurricane Isaac knocked down tree branches in Kenner, Louisiana. 
A child and an adult share a folding bed as storm-weary residents take refuge at a high school gymnasium in Belle Chasse, in low-lying Plaquemines Parish, outside of New Orleans. 
A tree toppled by Isaac stretches across the roof of a food stand in Arabi, Louisiana. 
A tree blown over from Hurricane Isaac lies atop a cemetery tomb in Plaquemines Parish. 
A street sign lies near floodwaters fromIsaac on Wednesday, in Braithwaite, Louisiana. Dozens were reportedly rescued in the area after levees were overtopped by floodwaters from Hurricane Isaac. 
A rescue boat passes a partially submerged stop sign. 
A car drives down Canal Street on Wednesday. The storm is slowly moving across southeast Louisiana, dumping large amounts of rain and knocking out power in scattered parts of the state. 
A traffic light continues to glow after being downed by Isaac's winds. 
A fallen tree blocks a road in New Orleans as Isaac batters the city and surrounding region, flooding homes and driving stormy waters over the top of at least one levee. 
Dozens were reportedly rescued in Plaquemines Parish after levees were overtopped by floodwaters. 
John Stone of Bay St. Louis, Mississippi, and his dog are led out of the water by a member of the Swift Water Rescue Team after being rescued from his flooded house. 
A tree was pushed over outside Tulane Medical Center in New Orleans. 
People rest in a rescue truck atop a levee in Plaquemines Parish. 
Rescue workers survey the floodwaters from a levee in Braithwaite. 
A downed streetlight lies in the rain in New Orleans' Central Business District. 
Police officers stand watch in the French Quarter. 
A traffic light dangles at an intersection in Metairie, Louisiana, during strong wind and rain as Hurricane Isaac pushes ashore. 
A tree toppled by hurricane-force winds lies on power lines near a home in New Orleans. 
A storm surge causes water to quickly rise while waves pound the concrete seawall along the shores of Lake Pontchartrain in New Orleans on Tuesday, August 28. 
Scott Burley runs from crashing surf on the Ken Combs Pier in Gulfport, Mississippi. 
Jason Preston closes shutters on a home in Gulfport, Mississippi, as Hurricane Isaac approaches. 
Emily Schneider leans against a pole to support herself against strong winds while visiting the banks of Lake Pontchartrain in New Orleans, where Hurricane Isaac has made landfall. 
Water rises from a bayou, flooding properties ahead of the arrival of Hurricane Isaac in Bay St. Louis, Mississippi. 
Bridgette Mooney, her husband Kevin, and their 15-month-old daughter Skyler watch from their home as Hurricane Isaac lashes their property with rain in Kiln, Mississippi. 
Employees of the Orleans Levee District remove signs from Lake Shore Drive near the shore of Lake Pontchartrain. 
Evan Stoudt faces strong winds from the banks of Lake Pontchartrain. 
A man walks on Canal Street in New Orleans. 
Joshua Keegan and Ruffin Henry swim at Lake Pontchartrain. 
High surf splashes along Highway 193 north of the Dauphin Island Bridge in Alabama. 
Waves from Hurricane Isaac smash against a warning sign at a flooded beach in Biloxi, Mississippi. 
A group of men sit on a bench at the edge of Lake Pontchartrain as Hurricane Isaac approaches. 
Matthew Pettus holds a sheet open in the wind on the levee near Lake Pontchartrain. 
People make their way across Canal Street in New Orleans. 
Joshua Keegan and his dog Scout swim in the rising water of Lake Pontchartrain. 
A Mississippi Department of Transportation sign in Hattiesburg warns southbound motorists on U.S. 49 of rough weather conditions on Tuesday, August 28. Hurricane Isaac is expected to drop heavy rain on the Mississippi Coast over the next couple of days. 
A woman and her dog watch the waves produced by Hurricane Isaac on the shore of Lake Pontchatrain in New Orleans on Tuesday. Hurricane Isaac is expected to make landfall later tonight along the Louisiana coast. 
Louisiana Gov. Bobby Jindal and New Orleans Mayor Mitch Landrieu receive an update on the status of the pumping station at the 17th Street Canal in Metairie, Louisiana. 
A couple takes photos in Bay St. Louis, Mississippi. Many residents of the area decided to stay in their homes instead of evacuating. 
A man skateboards past a bar with boarded windows in the French Quarter in New Orleans. 
Diana Whipple of New Orleans watches waves crash on the shore of Lake Pontchartrain as Hurricane Isaac approaches Tuesday. Isaac became a Category 1 hurricane Tuesday when its maximum sustained winds reached 75 mph, the National Hurricane Center says. 
Workers try to close off state Highway 23 South in Oakville, Louisiana, on Tueday as Issac heads toward the coast. 
Gallery Nine Forty in New Orleans' French Quarter notifies customers it's "on Hurrication." 
Workers board up a business on Bourbon Street in the French Quarter as Isaac approaches Tuesday. 
Hydraulic pumps are prepared at the 17th Street Canal floodwall Tuesday in New Orleans. 
A woman enjoys the a heavy rain in the Tampa, Florida, area, on Monday. Hurricane Isaac is expected to make landfall near New Orleans. 
Mounted law enforcement officials wait out a brief rainstorm during the National Republican Convention. Commercial bus cancellations caused by Isaac prevented many of the expected demonstrators from being present. 
A sign in the French Quarter makes fun of Hurricane Isaac. 
Workers place plywood on the windows of the Royal Sonesta Hotel on Bourbon Street. 
Aimo Ny rests on her cot in the hurricane shelter at the Belle Chasse Auditorium on Monday in Belle Chasse, Louisiana. 
iReporter Liz Yavinsky snapped this picture of a boy floating down a flooded street in West Palm Beach, Florida, on Monday. 
The manager of a shoe store in Harvey, Louisiana, places plywood over the windows in preparation of Hurricane Isaac. 
A crew from Jefferson Parish Drainage Department places large sandbags near a canal and pond in Jean Lafitte, Louisiana, on Monday in preparation for Isaac. 
A St. Petersburg, Florida, resident walks along the sea wall at Spa Beach, where larger than average waves were being kicked up by Tropical Storm Isaac on Monday. 
Oliver Marti sweeps water from heavy rains generated by Tropical Storm Isaac off the roof of his flower shop on Monday in Tampa, Florida. 
Waves batter the coast in Havana, Cuba, on Sunday after Tropical Storm Isaac passed the island. 
Larry Hoffmeister, left, and Charles Carter place storm shutters on Carter's vacation home on Dauphin Island, Alabama, as they prepare for Isaac on Sunday. 
Justin and Kayla Franklin of Tennessee walk in wind and rain in downtown Key West as Tropical Storm Isaac moves over the island. 
Biloxi, Mississippi, resident Stephanie Dale fills out paperwork Sunday to have her dog microchipped at the Humane Society of South Mississippi, which opened its doors to provide an emergency microchip and tag clinic. 
Ocean Springs, Mississippi, resident Charles Bartlett fills several gas containers in preparation for Isaac. 
Andrew Marino, left, and Colby Collier pull a wagon filled with sandbags back to their homes as Florida residents prepared for Tropical Storm Isaac in St. Pete Beach, Florida, on Sunday. 
Palm trees blow in the wind in front of the Tampa Bay Times Forum, where the start of the Republican National Convention was pushed to Tuesday. 
Earl, right, and Terri Harris place sandbags around their home to prepare for possible flooding. 
A couple watch as waves and strong winds from Tropical Storm Isaac, which crossed Cuba on Sunday, batter the shore in Gibara, Cuba, on Saturday. 
Strong winds bend palm trees in Cuba's northern province of Sancti Spiritus on Saturday. Isaac is expected to strengthen and become a Category 1 hurricane by early Monday as it draws nearer to Florida. 
A man captures the effects of Tropical Storm Isaac in Gibara. 
People watch from the shore as waves pound the coast in Gibara. 
Officials reported some storm surge and flooding in eastern Cuba. 
Tampa, Florida, area residents make preparations for the arrival of Tropical Storm Isaac by filling sandbags at a Hillsborough County Public Works Service Center on Saturday. 
A woman sits atop sandbags filled by Tampa area residents in preparation for the storm. 
Two men install storm shutters on Duval Street on Saturday. 
Vehicles cross a bridge leaving the Lower Keys on Saturday as the storm strengthens and moves closer. 
- Up to 3,000 people are being evacuated or rescued west of New Orleans, officials say
- Isaac's storm surge is forcing water over the banks of Lake Pontchartrain
- "Our main focus right now is getting people out of their homes," an official says
- Dusk-to-dawn curfews are in place from New Orleans to Baton Rouge, officials say
Have you been affected by Isaac? Share your photos here.
(CNN) -- National Guard troops were working early Thursday to evacuate thousands of people west of New Orleans after a storm surge brought on by hurricane-turned-tropical storm Isaac forced water over the banks of Lake Pontchartrain.
Dozens of buses were being used to move residents out of flooded portions of St. John Parish, while authorities worked to rescue others trapped by up to six feet of water.
"We're continuing to rescue people from different areas throughout the parish," said Paige Falgoust, communications director for St. John the Baptist Parish.
"Our main focus right now is getting people out of their homes."
Storm tracker By nightfall Wednesday, about 1,500 people were evacuated, and another 1,500 were expected to leave their homes, Gov. Bobby Jindal's office said.
President Barack Obama signed major disaster declarations for Louisiana and Mississippi after slow-moving Isaac pummeled the Gulf Coast, dropping more than 20 inches in some locations and creating a dangerous storm surge.
Some 840,000 people in Louisiana, Mississippi, Arkansas, Texas and Alabama were without power, and water boiling advisories were being issued in a number of towns and cities along the Gulf Coast.
Evacuee: 'The water kept coming' 
Hurricane Isaac's wall of water 
Plaquemines Parish residents rescued 
Isaac damages Billy Nungesser's house Airports from Baton Rogue to Biloxi were closed until at least Thursday as the stubbornly, slow-moving storm continued to saturate the region.
Isaac made landfall as a Category 1 hurricane, seven years to the day Hurricane Katrina swept ashore in Louisiana and Mississippi. Katrina killed 1,800 people, most in New Orleans after the levee system failed and the city flooded.
Isaac's greatest punch bypassed New Orleans, taking aim at surrounding communities.
The storm was just south of Baton Rogue early Thursday, moving at about 6 mph with maximum sustained winds of 60 mph, the National Weather Service said.
Dusk-to-dawn curfews were in effect from New Orleans to Baton Rouge, where authorities were urging residents to stay inside and ride out the slow moving storm.
The situation was particularly dire in Plaquemines Parish, southeast of New Orleans, where 3,000 people remained in one area close to an 8-foot tall levee that waters are threatening, Jindal's office said.
An initial estimate by local parish officials showed as many as 800 homes may have received significant water damage, Jindal said earlier.
The U.S. Army Corps of Engineers reported significant storm surge in the parish, scene of many rescues. One involved National Guard troops who moved 112 residents from the Riverbend nursing home to another facility.
Dozens of Louisiana families that had ignored mandatory evacuation orders in a low-lying area retreated to their attics and roofs and sought rescue amid the howling wind and pounding rain.
Officials were considering intentionally breaching the levee downstream to allow some of the floodwater to flow back out of the inundated area, Jindal said.
That could happen as early as Saturday, said Billy Nungesser, the parish president. A report, though, in the Times-Picayune newspaper said digging could begin as early as Thursday.
Captivating pictures from Isaac 
Father and son save lives in Louisiana 
Isaac flooding surrounds homes 
CNN reporters feel Isaac's fury "We are still looking for stranded residents," Nungesser said Wednesday night.
"We will resume a double check tomorrow on the homes on the east bank (of the Mississippi River). We're checking the west bank for anyone who may have been trapped."
While New Orleans reported relatively minor damage from the storm, officials said there were at least 12 incidents of looting in the city. New Orleans Police said arrests were made in each case, but didn't specify how many people were involved or where the arrests occurred.
In Mississippi, Gov. Phil Bryant said Wednesday that 34 people were rescued by boat in Hancock County, on the coast northeast of New Orleans, and 15 others were picked up by National Guard troops in trucks.
St. John Parish was virtually cut off Wednesday after Isaac's torrential rain and storm surge made nearly all roads in and out impassable, Falgoust said.
Parish officials were cross-matching records to make sure no residents were overlooked in the haste to get people out, Falgoust said.
The parish, with a population of about 32,000, was spared Katrina's devastation.
This time it wasn't so lucky.
The storm surge from Lake Ponchartrain came quickly and "in a different way from what we were expecting," Falgoust said.
The surge was unusually bad in LaPlace, about 25 miles northwest of New Orleans, where many people had been rescued or still needed to escape rapidly rising water.
"We have established pickup points in certain subdivisions that are easy access for our residents to get to by foot," she said.
People were being taken to a processing center at a church then bused to state shelters outside the parish.
"In some areas the water levels rose in 10 minutes to where they could not get out of their homes," she said.
CNN's Brian Todd, Soledad O'Brien, Ed Lavandera, Martin Savidge, John Zarrella, Chandler Friedman, Anika Chin, Mike Ahlers, Aaron Cooper and Ed Payne contributed to this report.
