(CNN) Rescue crews in the Carolinas worked methodically throughout the day on Monday, plucking people to safety from the flooding left by Hurricane Matthew's deadly haymaker.

Responders pulled people from their submerged homes, situated them in rafts or choppers and whisked them to safe and dry ground.

The storm's US death toll climbed to 21 on Monday, with North Carolina reporting 11 deaths , Florida reporting four, and three each in South Carolina and Georgia.

Federal funding is available to people in Beaufort, Bladen, Columbus, Cumberland, Edgecombe, Hoke, Lenoir, Nash, Pitt, and Robeson counties.

Photos: Hurricane Matthew's path of destruction Photos: Hurricane Matthew's path of destruction People wade through floodwaters with a boat in Nichols, South Carolina, on Monday, October 10. Hurricane Matthew caused flooding and damage in the Southeast -- from Florida to North Carolina -- after slamming Haiti and other countries in the Caribbean. Hide Caption 1 of 80 Photos: Hurricane Matthew's path of destruction Workers repair downed power lines in Daytona Beach, Florida, on October 10. Hide Caption 2 of 80 Photos: Hurricane Matthew's path of destruction Rescue teams maneuver through floodwaters in Lumberton, North Carolina, on October 10. President Barack Obama has declared a major disaster in North Carolina and ordered federal aid to supplement state, tribal and local recovery efforts. Hide Caption 3 of 80 Photos: Hurricane Matthew's path of destruction Floodwaters inundate a home in Lumberton on October 10. Hide Caption 4 of 80 Photos: Hurricane Matthew's path of destruction Floodwaters surround a house in Nichols, South Carolina, on October 10. Hide Caption 5 of 80 Photos: Hurricane Matthew's path of destruction South Carolina Gov. Nikki Haley checks flooding near Nichols on October 10. Hide Caption 6 of 80 Photos: Hurricane Matthew's path of destruction Floodwaters surround power lines near Nichols on October 10. Hide Caption 7 of 80 Photos: Hurricane Matthew's path of destruction Without power in the hurricane's aftermath, Missy Zinc shines a light so her husband, Shawn, can prepare steaks to grill in Hilton Head, South Carolina, on Sunday, October 9. Hide Caption 8 of 80 Photos: Hurricane Matthew's path of destruction Anthony Writebol, left, and his cousin Melissa Hill paddle past a stranded tractor-trailer in Lumberton on October 9. Hide Caption 9 of 80 Photos: Hurricane Matthew's path of destruction A man clings to a road sign after trying to swim out to help a stranded truck driver in Hope Mills, North Carolina, on October 9. Both were rescued. Hide Caption 10 of 80 Photos: Hurricane Matthew's path of destruction People stop and take pictures of Highway 58, which was flooded in Nashville, North Carolina, on October 9. Hide Caption 11 of 80 Photos: Hurricane Matthew's path of destruction Boats are pushed up among twisted docks in Hilton Head on October 9. Hide Caption 12 of 80 Photos: Hurricane Matthew's path of destruction Rescue workers help several dogs that were trapped in homes in Pinetops, North Carolina, on October 9. Hide Caption 13 of 80 Photos: Hurricane Matthew's path of destruction A section of Wayne Memorial Drive was washed out in Goldsboro, North Carolina. Hide Caption 14 of 80 Photos: Hurricane Matthew's path of destruction John Tweedy wades into the swift-moving floodwaters surrounding his business in McClellanville, South Carolina, on Saturday, October 8. Hide Caption 15 of 80 Photos: Hurricane Matthew's path of destruction A woman who gave her name only as Valerie walks along flooded President Street after leaving her homeless camp in Savannah, Georgia, on October 8. Hide Caption 16 of 80 Photos: Hurricane Matthew's path of destruction Volunteers clear debris from from a pool at a condominium complex in Jacksonville Beach, Florida, on October 8. Hide Caption 17 of 80 Photos: Hurricane Matthew's path of destruction A police officer steps through the remnants of a home leveled by Hurricane Matthew in the tiny beach community of Edisto Beach, South Carolina, on October 8. Hide Caption 18 of 80 Photos: Hurricane Matthew's path of destruction A downed tree and power lines block a road on Georgia's St. Simons Island on October 8. Hide Caption 19 of 80 Photos: Hurricane Matthew's path of destruction A woman fights the wind in Wrightsville Beach, North Carolina, on October 8. Hide Caption 20 of 80 Photos: Hurricane Matthew's path of destruction Parts of Highway A1A in Flagler Beach, Florida, were washed away by Hurricane Matthew on Friday, October 7. Hide Caption 21 of 80 Photos: Hurricane Matthew's path of destruction Water flows over a seawall and fills the streets of St. Augustine, Florida, on October 7. Hide Caption 22 of 80 Photos: Hurricane Matthew's path of destruction Barbara Hearst tapes her storm shutters as Hurricane Matthew nears Charleston, South Carolina, on October 7. Hide Caption 23 of 80 Photos: Hurricane Matthew's path of destruction Adam and Alec Selent watch waves crash over a retainer wall at the Ocean Club condominiums in Isle of Palms, South Carolina, on October 7. Hide Caption 24 of 80 Photos: Hurricane Matthew's path of destruction A damaged boat sits partially submerged on the intercoastal waterway in Melbourne, Florida, on October 7. Hide Caption 25 of 80 Photos: Hurricane Matthew's path of destruction A police officer helps persuade a woman to board a bus and evacuate Savannah, Georgia, on October 7. Hide Caption 26 of 80 Photos: Hurricane Matthew's path of destruction Preston Payne tries to hold his umbrella on Georgia's Tybee Island on October 7. Hide Caption 27 of 80 Photos: Hurricane Matthew's path of destruction Heavy waves pound boat docks in Cocoa Beach, Florida, on October 7. Hide Caption 28 of 80 Photos: Hurricane Matthew's path of destruction A women helps a dog walk through floodwaters in Port Orange, Florida, on October 7. Hide Caption 29 of 80 Photos: Hurricane Matthew's path of destruction Damage in Cocoa Beach. Hide Caption 30 of 80 Photos: Hurricane Matthew's path of destruction Waves crash against a bridge in St. Augustine, Florida. Hide Caption 31 of 80 Photos: Hurricane Matthew's path of destruction A car drives past a downed tree as the hurricane moves through Daytona Beach, Florida, on October 7. Hide Caption 32 of 80 Photos: Hurricane Matthew's path of destruction A billboard canvas flaps in the wind after Hurricane Matthew passed North Palm Beach, Florida, on October 7. Hide Caption 33 of 80 Photos: Hurricane Matthew's path of destruction A woman inspects her damaged car under a tree in Fort Pierce, Florida, on October 7. Hide Caption 34 of 80 Photos: Hurricane Matthew's path of destruction A space shuttle model stands near some downed trees after Hurricane Matthew passed by Cocoa Beach. Hide Caption 35 of 80 Photos: Hurricane Matthew's path of destruction A woman uses her phone under a battery-operated lantern at a hotel in Titusville, Florida, on October 7. Hide Caption 36 of 80 Photos: Hurricane Matthew's path of destruction Palm trees on Cocoa Beach sway in the wind on October 7. Hide Caption 37 of 80 Photos: Hurricane Matthew's path of destruction Firefighters respond to a pre-dawn house fire in Satellite Beach, Florida, that was possibly caused by a downed power line on October 7. Hide Caption 38 of 80 Photos: Hurricane Matthew's path of destruction Heavy rain billows in front of Exploration Tower in Cape Canaveral, Florida, on October 7. Hide Caption 39 of 80 Photos: Hurricane Matthew's path of destruction People stand on a beach in Broward County, Florida, as the storm approached the coast on Thursday, October 6. Hide Caption 40 of 80 Photos: Hurricane Matthew's path of destruction A police officer walks along the beach in Singer Island, Florida, on October 6. Hide Caption 41 of 80 Photos: Hurricane Matthew's path of destruction Kevin Forde and John Haughey put plywood on a Miami Beach window on October 6. Hide Caption 42 of 80 Photos: Hurricane Matthew's path of destruction Hurricane Matthew moves through Paradise Island in Nassau, Bahamas, on October 6. Capt. Stephen Russell, the head of the Bahamas National Emergency Management Authority, said there were many downed trees and power lines but no reports of casualties. Hide Caption 43 of 80 Photos: Hurricane Matthew's path of destruction People leave Disney's Magic Kingdom theme park, in heavy rain, after it closed in Orlando, Florida in preparation for the landfall of Hurricane Matthew, on October 6. Hide Caption 44 of 80 Photos: Hurricane Matthew's path of destruction A man rakes up debris from a storm drain as he begins cleanup near a damaged gas station in Nassau on October 6. Hide Caption 45 of 80 Photos: Hurricane Matthew's path of destruction Residents repair their homes in Les Cayes, Haiti, on October 6. The damage from Hurricane Matthew was especially brutal in southern Haiti, where sustained winds of 130 mph punished the country. Hide Caption 46 of 80 Photos: Hurricane Matthew's path of destruction Girls hold hands as they help each other wade through a flooded street in Les Cayes on October 6. Hide Caption 47 of 80 Photos: Hurricane Matthew's path of destruction Two days after the storm, authorities and aid workers in Haiti still lacked a clear picture of what they fear is the country's biggest disaster in years. Hide Caption 48 of 80 Photos: Hurricane Matthew's path of destruction A supermarket shelf is nearly cleared out in Titusville, Florida, on Wednesday, October 5. Hide Caption 49 of 80 Photos: Hurricane Matthew's path of destruction Bumper-to-bumper traffic lines Interstate 26 in Columbia, South Carolina, as people drive west on October 5. Hide Caption 50 of 80 Photos: Hurricane Matthew's path of destruction Workers start removing umbrellas and the colorful rocking chairs that line the Cocoa Beach Pier in Cocoa Beach, Florida, on October 5. Hide Caption 51 of 80 Photos: Hurricane Matthew's path of destruction People carry a coffin and try to cross the La Digue river on October 5 after a bridge collapsed in Petit-Goave, Haiti. Hide Caption 52 of 80 Photos: Hurricane Matthew's path of destruction People cross the La Digue river on October 5. Hide Caption 53 of 80 Photos: Hurricane Matthew's path of destruction Evacuees return to their homes in the Carbonera community of Guantanamo, Cuba, on October 5. Hide Caption 54 of 80 Photos: Hurricane Matthew's path of destruction People embrace at their damaged home in Baracoa, Cuba. The hurricane rolled across the sparsely populated tip of Cuba, destroying dozens of homes in the country's easternmost city and leaving hundreds of others damaged. Hide Caption 55 of 80 Photos: Hurricane Matthew's path of destruction A woman cries amid the rubble of her home in Baracoa. Hide Caption 56 of 80 Photos: Hurricane Matthew's path of destruction Bus drivers in North Charleston, South Carolina, wait for word to start evacuations. Hide Caption 57 of 80 Photos: Hurricane Matthew's path of destruction The high winds of Hurricane Matthew roar over Baracoa on Tuesday, October 4. Hide Caption 58 of 80 Photos: Hurricane Matthew's path of destruction Beth Johnson fills up her car at a gas station in Mt. Pleasant, South Carolina, on October 4. Hide Caption 59 of 80 Photos: Hurricane Matthew's path of destruction The mother of two girls who died in the storm is comforted near her home in Santo Domingo, Dominican Republic, on October 4. The girls were killed when a landslide caused by flooding breached the walls of their house. Hide Caption 60 of 80 Photos: Hurricane Matthew's path of destruction A worker clears a sewer on a flooded street in Santo Domingo. Hide Caption 61 of 80 Photos: Hurricane Matthew's path of destruction Anita Baranyi feeds her baby while keeping an eye on the generator she intends to purchase from a home-improvement store in Oakland Park, Florida, on October 4. Hide Caption 62 of 80 Photos: Hurricane Matthew's path of destruction People wade through the flooded streets of Cite Soleil in the Haitian capital of Port-au-Prince on October 4. Hurricane Matthew is the strongest storm to hit Haiti since 1964 and the first hurricane to make landfall in the country since the devastating earthquake in 2010. Hide Caption 63 of 80 Photos: Hurricane Matthew's path of destruction People observe the flooding of a river near Port-au-Prince on October 4. Hide Caption 64 of 80 Photos: Hurricane Matthew's path of destruction Children swim in a flooded neighborhood of Santo Domingo on October 4. Hide Caption 65 of 80 Photos: Hurricane Matthew's path of destruction A truck used as public transportation drives through flooded streets in Port-au-Prince on October 4. Hide Caption 66 of 80 Photos: Hurricane Matthew's path of destruction Hurricane winds blow against palm trees in Port-au-Prince. Hide Caption 67 of 80 Photos: Hurricane Matthew's path of destruction A food vendor lays out goods for sale during a light rain in Port-au-Prince on October 4. Hide Caption 68 of 80 Photos: Hurricane Matthew's path of destruction Haitian civil protection workers arrive to evacuate the Tabarre region of Haiti on October 3. Hide Caption 69 of 80 Photos: Hurricane Matthew's path of destruction Officials urge residents to evacuate their homes in the Grise River area of Tabarre on October 3. Hide Caption 70 of 80 Photos: Hurricane Matthew's path of destruction Clouds loom over the hills of the Petionville suburb of Port-au-Prince on October 3. Hide Caption 71 of 80 Photos: Hurricane Matthew's path of destruction Families seek shelter from Hurricane Matthew at a university facility in Guantanamo, Cuba. Hide Caption 72 of 80 Photos: Hurricane Matthew's path of destruction People near Kingston, Jamaica, take a photo in front of the rough surf produced by Hurricane Matthew on October 3. Hide Caption 73 of 80 Photos: Hurricane Matthew's path of destruction A backhoe removes garbage to clear a canal in Port-au-Prince on October 3. Hide Caption 74 of 80 Photos: Hurricane Matthew's path of destruction Nice Simon, the mayor of Tabarre, Haiti, holds a baby as she helps evacuate the area along a river. Hide Caption 75 of 80 Photos: Hurricane Matthew's path of destruction People stock up on food at a supermarket in Port-au-Prince on Sunday, October 2. Hide Caption 76 of 80 Photos: Hurricane Matthew's path of destruction A worker dismantles a traffic light in Santiago before Hurricane Matthew struck Cuba. Hide Caption 77 of 80 Photos: Hurricane Matthew's path of destruction Motorists drive through heavy rains in Kingston, Jamaica, on October 2. Hide Caption 78 of 80 Photos: Hurricane Matthew's path of destruction Residents of Cuba's Holguin Province line up to buy gas on October 2. Hide Caption 79 of 80 Photos: Hurricane Matthew's path of destruction A worker nails a board to a storefront window in Kingston on Saturday, October 1. Hide Caption 80 of 80

Flooding in Lumberton

In the eastern North Carolina city of Lumberton, in one of the counties included in the President's disaster declaration, rescuers worked to save 1,500 people stranded by flooding.

"We have people on roofs (there) as we speak," North Carolina Gov. Pat McCrory said earlier Monday.

The Federal Aviation Administration has ordered flight restrictions over the area so helicopters can rescue them.

Kellie Blue, Robeson County, North Carolina, spokeswoman, said around 3,000 people were sent to shelters after the flooding but the county has no precise figure on the total number residents forced from their homes.

She said ice and water were being shipped in because about 26,000 utility customers in the county lacked water.

Utility crews were working to repair water lines but once water mains were fixed, another road was washed out, and lines burst again.

At one point, she said, people were evacuated to a shelter that had to be evacuated because of flooding.

There are 800 residents living in an evacuation shelter at a high school. Four people remain missing in the county, she said.

Homes, restaurants and business have been lost, she said.

"Our board of education is destroyed," Blue said. "It's completely underwater."

The state reported the evacuation of a prison threatened by flooding. Authorities said 797 inmates from the Neuse Correctional Institution in Goldsboro were taken to other prisons in the state system.

The minimum-security facility for male inmates is near downtown Goldsboro and near the confluence of the Little River and the Neuse River.

JUST WATCHED Man rescued from flood waters Replay More Videos ... MUST WATCH Man rescued from flood waters 00:56

Taking shelter at a town hall

Authorities in Marion County, South Carolina, used boats and helicopters to rescue the last members of a group of 150 people who sought shelter against the Lumber River in the Nichols, South Carolina, town hall.

People had been in the town hall since 9 p.m. Sunday, according to Kent Williams, who is the Marion County deputy administrator and a state legislator.

"With the Lumber River and all the rain that Matthew dumped on us, it was more than they could handle. That was pretty much the safest place for them to be," Williams said. "The town hall was the high ground."

Rescue teams took them to a middle school in Mullins.

"The water is rising so fast it's scary. The river is not scheduled to crest until ten in the morning. It's the worst we've seen it," Williams said.

Massive power outages

About 500,000 structures in North Carolina didn't have power Monday.

"That's probably well over 1 million people without power," McCrory said. "That's 10% of our population in North Carolina -- all in a very small area. At least 10%."

Crews continue restoration efforts in the Carolinas. Estimated times for restoration available at our website: https://t.co/1WRWexc6lA pic.twitter.com/JgSvHdXUmU — Duke Energy (@DukeEnergy) October 10, 2016

More than 469,000 South Carolina customers didn't have power Monday, Gov. Nikki Haley said. She said 8,000 linemen were working to get electricity restored.

And Florida, the first state thrashed by Matthew, still had 169,000 customers without power Monday, Gov. Rick Scott's office said.

Matthew also played havoc with the state's voter registration process. On Monday, a court extended the voter registration deadline because evacuations.

Meanwhile, the state is working to get back to normal. The Kennedy Space Center will reopen on Tuesday at 6 a.m. Employees are being asked to report to work at their regular times. At the same time, recovery operations are continuing and people are asked to be careful on their return.

Dead and missing

The 11 deaths in North Carolina included some victims who drowned after driving onto flooded roads.

A tree crushed a trailer in Hilton Head, South Carolina, over the weekend.

"I cannot stress more: If you see a road that's flooded, do not take your car through that road," McCrory said. "If you see a barrier, do not go around that barrier."

Another five people remain missing in North Carolina, McCrory said.

In South Carolina, 66-year-old David L. Outlaw drowned when his wheelchair got pinned down in standing water at a nursing facility's courtyard, Richland County Coroner Gary Watts said.

Along with the 21 official storm-related deaths in the United States, a member of a tree-removal crew in Florida clearing debris in left behind by Hurricane Matthew lost his life on Monday when a large log rolled on top of him. The incident occurred shortly before 6 p.m. in the Halifax Plantation community near Ormond Beach in Volusia County's extreme northeast corner, not far from the border with Flagler County.

The US deaths came after Matthew devastated parts of the Caribbean, killing more than 300 people in Haiti, said Paul Altidor, Haitian ambassador to the United States. Others report much higher death tolls.

More 'catastrophic flooding' on the way

A man holds onto a sign after trying to swim out to help a stranded truck driver in Hope Mills, North Carolina, on Sunday.

Forecasters warned of more "catastrophic flooding" as North Carolina residents braced for swollen rivers to top their banks in the next few days.

"River levels will rise above major flood stage this morning and remain elevated well into next week," the National Weather Service said.

.@NWSMoreheadCity AM river flood briefing shows several E NC cities expected to reach major flood levels #MatthewNC https://t.co/Oov2KmWE4C pic.twitter.com/3Htm56iz6H — NC Public Safety (@NCPublicSafety) October 10, 2016

What to do next

As more storm victims return to their homes from Florida to North Carolina, it's critical to know how to come back safely.

As you clean up after #MatthewNC be safe as you clear away fallen limbs and trees from roads, houses and yards https://t.co/sILNhPr0Fk pic.twitter.com/wJWvbv4P5j — NC Emergency Managem (@NCEmergency) October 10, 2016

In addition to avoiding all flooded roads, keep an eye out for downed power lines and weakened bridges and roads that look like they might collapse, the National Weather Service said.

Once back home, "walk carefully around the outside of your home to check for loose power lines, gas leaks and structural damage," the NWS said. "Stay out of any building if you smell gas."

JUST WATCHED What's left in Florida after Hurricane Matthew Replay More Videos ... MUST WATCH What's left in Florida after Hurricane Matthew 01:16

The agency said carbon monoxide poisoning is one of the leading causes of death after storms involving power outages.

"Never use a portable generator inside your home or garage," the NWS said. "Use battery-powered flashlights. Do not use candles. Turn on your flashlight before entering a vacated building. The battery could produce a spark that could ignite leaking gas, if present."

North Carolina's Department of Public Safety offers additional tips on how to safely remove trees and limbs from homes.

Beach house turns into a beach

Grant Lynch garnered national attention last week when he posted video of Matthew's mammoth waves clobbering his Florida beach house

He returned to his Palm Coast home over the weekend to find the house filled with beach sand.

He tried to walk inside the house, whose floors were covered by what looked like more than a foot of sand.

"My head's almost hitting the roof," he said.