WASHINGTON — Louisiana has faced epic flooding, with six people killed and thousands evacuated to emergency shelters after waterways in the southern part of the state overflowed their banks.

Some areas have received more than 50 centimetres of rain since late Thursday, submerging vast swaths of southern Louisiana in muddy waters.

"Our state is currently experiencing a historic flooding event that is breaking every record," Louisiana governor John Bel Edwards said in a statement to residents on late on Monday.

"This event is ongoing, it is not over," he said. "We do not know when the floodwaters will recede, and they will continue to rise in some areas."

Six people have been killed and more than 20,000 others forced to evacuate their homes, officials said.

Massive shelters are housing the displaced, including at a Baton Rouge film studio complex and an entertainment center in the state capital’s downtown area. Police said the Louisiana National Guard will assist evacuees in emergency shelters.

A helicopter survey on late Monday by the East Baton Rouge Sheriff’s Office showed large areas of submerged land. Muddy water covered roads, forested areas, and residential zones, cars and even the better part of some dwellings.

A spokeswoman for Edwards, Shauna Sanford, said six people have been killed in the floods. Some 40,000 homes and business were reported without power.

Disaster areas

The White House declared four parishes - equivalent to counties in other states - major disaster areas.

"I fully expect that more parishes will be added to the declaration on a rolling basis," Edwards said.

Floodwaters appeared to be receding in some areas, but were flowing into others. The National Weather Service predicted that many waterways would remain above flood stage into at least Tuesday.

The agency continued to issue flood warnings in effect through early Tuesday, saying water in many areas would not recede at least for another day.

The Amite River, the source of flooding for many areas, had risen 14 feet above flood level in one reading, besting a previous record flood in April 1983, the NWS said.

The agency forecasted that the Amite won’t fall below flood level until Wednesday morning.

Officials reported that hundreds of roads, most in the southern parts of the state, were closed due to flooding.

"That’s going to be the case over the next couple of days," Edwards said.

Offers of aid

The White House action makes emergency federal funding available to support rescue crews and recovery efforts.

The Federal Emergency Management Agency on Monday began asking those affected by the floods to apply for assistance, and officials said 11,000 people had already registered early in the day.

The American Red Cross said it was responding to the disaster, which it called the worst since Superstorm Sandy flooded coastal areas in New York and New Jersey in 2012.

Many parishes in Louisiana were collecting donations for flood victims.

At neighboring Lafourche Parish, officials were accepting donations, including "non-perishable food items," bottled water and blankets.

At Iberia Parish, officials were collecting school uniforms, clothes, bedding, and personal hygiene products, among other items.

At Plaquemines Parish, officials said two airboat rescue teams had returned after assisting in East Baton Rouge, where they rescued more than 200 people and pets from various parts of the parish over a 24-hour period.

Dramatic rescues

The Louisiana National Guard reported that its soldiers rescued nearly 500 people and 61 pets in the 24 hours between Friday and Saturday, by boat, helicopter, and using high-water vehicles.

"We’ve literally had hundreds of people who’ve brought boats in and have wanted to help," said Michael Edmonson, the superintendent of Louisiana State Police.

In one dramatic rescue in Baton Rouge captured on video, rescuers on a boat pulled a woman from a car that had just slipped under water.

The woman shouts, "Oh my God, I’m drowning!"

A rescuer jumps into the murky brown water and pulls her out by the arm.

When she tries to dive under for her dog, he dives underwater and reappears holding the animal.

The NWS said other areas of the United States faced threats of flash floods this week -- from the Texas coast all the way up to the Ohio River Valley.

The storms threatening Texas are part of the same system, although slightly less potent, that deluged Louisiana, said NWS meteorologist Gavin Phillips.

"The low, as it’s moved into the Texas area, it’s weakened a lot," Phillips said, so the state is not expected to get as much rain. — AFP