Tens of thousands of New Orleans residents could begin returning to their homes as early as Monday as city and federal authorities have set out an accelerated plan to repopulate the city, reversing earlier estimates that the metropolis could be closed for months.

The plan would reopen a portion of New Orleans that was home to about 170,000 people, or one-third of the city's population, federal officials said, and be rolled out over the next two weeks.

The reentry plan would unfold by Zip code, depending on which section gets power and water utilities online, and how quickly hospital and emergency services can be restored. It involves portions of New Orleans that largely were unflooded: downtown, the French Quarter, Uptown and Algiers.

"The timing of the plan is subject to getting security and health issues in order," said William Lehman, the Federal Emergency Management Agency spokesman for Orleans Parish.

Other portions of the city could remain uninhabited for months, authorities said, as tens of thousands of homes must be drained and many rebuilt.

The legal and political disputes over how authorities responded to Hurricane Katrina also promise to persist, as controversy flared over nursing homes and hospitals that did not evacuate, and over the recovery of the dead.

Louisiana state authorities said Wednesday that they are investigating the Lafon Nursing Home of the Holy Family in New Orleans, where a number of deaths have been reported. They may investigate as many as 18 nursing homes, authorities said.

The state has charged the owners of St. Rita's nursing home in St. Bernard Parish with 34 counts of negligent homicide stemming from patient deaths in flooding from Katrina. State Attorney General Charles C. Foti Jr. said that the owners of the nursing home, Salvador and Mable Mangano, had a legal obligation to evacuate the home.

The couple's attorney, James Cobb, said that his clients did not evacuate their 60 patients because they believed that their nursing home was safe -- it had never flooded in 20 years -- because St. Bernard Parish officials never ordered a mandatory evacuation and because the Manganos believed that transporting their patients en masse by bus could kill them.

Cobb cited numerous reports of elderly people dying during the evacuation before Katrina. "What do you do? You know if you evacuate, 10, 12 or 14 -- pick a number -- might die on the way out," he said in a cell phone interview.

He described the efforts the Manganos and their children made to rescue patients after the nursing home flooded, getting them onto mattresses to float out through broken windows, and then into boats. "They saved 52 lives," Cobb said. "And their reward . . . is an arrest warrant."

The owners of a New Orleans hospital where 44 bodies were found said they were those of critically ill patients who died in stifling heat after power was cut to the flooded building. Tenet Healthcare Corp. said no one still alive was left behind at Memorial Medical Center in New Orleans.

The death toll for Louisiana reached 474 as the recovery of bodies continued. In response to criticism from Louisiana Gov. Kathleen Babineaux Blanco (D) that the federal effort to bring bodies to the morgues was going too slowly and showed disrespect for the dead, the official in charge of hurricane recovery described a process in which a chaplain accompanied each search team and recited a prayer whenever a body was discovered.

"This is a sensitive process," Vice Adm. Thad W. Allen said at a news conference. "We are mindful of the dignity needed to be afforded each individual."

Less than half the city is now underwater, down from 80 percent at the peak of the flooding. Of the 144 pumps in Orleans Parish, 80 have begun working, Lehman said, up from 20 just days ago. About 50 percent of the phone lines are working, he said.

"We are out of nuclear crisis mode and are into day-to-day crisis mode," Mayor C. Ray Nagin said Tuesday night. He said his decision on reentry, which is expected to be announced Thursday, will depend on air and water quality in the city. According to the Environmental Protection Agency, "every effort should be made to limit contact with flood water due to potentially elevated levels of contamination associated with raw sewage and other hazardous substances." But Nagin said that test results have generally been better than expected.

In the suburbs outside of the heavily hit areas of Orleans, St. Bernard and Plaquemines parishes, residents have begun to come back, waiting either for electricity or the grocery store.

In New Orleans, even those streets in areas least affected by the storm are badly in need of cleanup. Stoplights do not work. Outside restaurants, the stench from two weeks' worth of rotten food is sometimes overpowering. Broken glass litters sidewalks and gutters. In places, fallen brick walls block roadways.

Yet amid the debris, restoration crews and armed troops on the streets Wednesday, some residents were looking forward again -- almost optimistically.

About midmorning, restaurateur Alex Patout was sitting outside his famed French Quarter establishment, sipping champagne.

"Thank God the heart and soul of what New Orleans is all about is basically damage-free," he said. "All we need is electricity -- we want to be one of the first restaurants to open."

He was planning his first menus, but he acknowledges that he is facing a daunting challenge. Of his staff of 40, many of whom lived in east New Orleans, he has located only one.

As he sees it, New Orleans has been split into two very different halves, one flooded, the other dry. Though the dry portion may be better off in some ways, the businesses there depend on the less-fortunate parts for employees.

"That is going to be the biggest nut for this city," he said. "Where is the human infrastructure that makes it run?"

Trial lawyer Steven J. Rando, dressed for wading in deep water, heads to his car on Canal Street to retrieve cleaning supplies. Residents have not been given the official all-clear to come back.Rando struggles to haul a water-drenched carpet from his office. Less than half the city is still submerged.