As CBS News Correspondent Lee Cowan reports nearly 10,000 came to the Superdome with no where else to go. They were either too sick, too old or too poor to flee from the storm.
"They're in for another miserable night," Terry Ebbert, chief of homeland security for New Orleans, said Monday afternoon. But he later added: "They're safe."
Superdome and government emergency officials stressed that they did not expect the huge roof to fail because of the relatively small breaches, each about 15 to 20 feet long and 4 to 5 feet wide.
Refugees sitting below the holes were moved across the arena and away from any falling debris, said Doug Thornton, regional manager of the company that manages the huge arena.
"I could have stayed at home and watched my roof blow off," said one of the refugees, Harald Johnson, 43. "Instead, I came down here and watched the Superdome roof blow off. It's no big deal; getting wet is not like dying."
In addition to the two holes, water was leaking in through many other areas, including elevators and stairwells, as the wind forced water in through any small opening. Across Poydras Street, numerous shattered windows were visible on high-rise office buildings.
Glenn Menard, general manager of the Superdome, said that although only the two holes were visible from the interior, more damage was possible.
The 77,000-seat, steel-framework stadium, home of the NFL's New Orleans Saints, provided few comforts but at least had bathrooms and food donated by charities.
The wind that howled around the dome during the night was not heard in the interior of the building where the refugees were kept.
"Everybody slept last night. They didn't seem to have any problems," said Dr. Kevin Stephens Sr., in charge of the medical shelter in the Superdome. "They slept all over the place."
Power failed around 5 a.m., triggering groans from the crowd. Emergency generators kicked in but they run only reduced lighting, not the air conditioning. The inside of the Superdome quickly became very hot, and condensation made some floors wet and slippery.
The Superdome opened its doors at noon Sunday, and New Orleans' most frail residents got priority. The stadium is by far the most solid of the Big Easy's 10 refuges for the estimated 100,000 city residents who don't have the means, or strength, to join a mandatory evacuation.
"They hadn't opened up and let us in here, there'd have been a lot of people floating down river tomorrow," said Merrill Rice, 64. "If it's as bad as they say, I know my old house won't stand it."
Residents lined up for blocks as National Guardsman searched them for guns, knives and drugs. It was almost 10:30 p.m. before the last person was searched and allowed in. "We've got sick babies, sick old people and everything in between," Stephens said. "We're seen strokes, chest pain, diabetes patients passing out, seizures, people without medicine, people with the wrong medicine. It's been busy."
Thornton worried about how everyone would fare over the next few days.
"We're expecting to be here for the long haul," he said. "We can make things very nice for 75,000 people for four hours. But we aren't set up to really accommodate 8,000 for four days."
Morris Bivens, 53, a painter, came to the dome with his wife, daughter and five granddaughters ranging in age from 1 to 9.
"I had to come," he said. "Not for me. I ride these out all the time. But I knew I couldn't save those children in this one if something happened."