Patricia Cain entered the George R. Brown Convention Center barefoot and carrying two oxygen tanks. The first was empty. The second was given to her by the Houston Fire Department after the U.S. Coast Guard rescued her from her flooded home.
She suffers from congestive heart failure, among other illnesses. Her son, William, and 9-year-old grandson were waiting for her inside. Both were barefoot as well.
"I live in a lake where there was once dry land," William Cain said.
The Cains were among hundreds of people who arrived Sunday by boat, by bus, and by foot to Houston's showcase convention center downtown, transformed by volunteers with few hours' notice into a shelter as Harvey ravaged Houston.
Weary and carrying little more than what was in their pockets, they prepared for what could be several days inside the convention center. Many of the roads and major highways nearby were impassable. The American Red Cross was expanding the shelter by the hour as more people arrived, including dozens of volunteers and local residents who saw reports on the news or social media and brought bags of donations.
Inside a cavernous hall humming with the sound of hundreds of conversations, volunteers served food, handed out towels and set up tables with donated clothes for a long line of evacuees. Some people huddled around a projection screen showing television coverage of the storm. Others collected bowls of pasta with parmesan cheese and cups of black coffee.
A long line of people carrying blankets and pillows waited to enter a separate space in the convention center serving as the dormitory. Volunteers had set out around 1,300 cots and were quickly assembling more in anticipation of other evacuees arriving through the night. They have enough space and cots to house 5,000 people. Police officers and medics stood ready, though there were no reports of arrests or major incidents Sunday.
"We feel that we have the resources and the knowledge not to have this be anything but safe for families, children and others who need support and safety," said U.S. Rep. Sheila Jackson Lee, D-Houston, who visited the shelter Sunday.
The American Red Cross mobilized at the convention center on a few hours' notice, said Ken Sandy, a shelter manager. The city of Houston had publicly announced just two shelters Saturday night, as the worst of the rain that pelted Houston and surrounding Harris County began. One of the shelters had to close because it was too close to high water.
Houston Mayor Sylvester Turner then announced Sunday morning that the convention center would become a shelter. A few hours later, the first group of evacuees arrived.
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Most of the people at the shelter were African-American or Latino, and many of their stories reflected how Harvey affected low-income neighborhoods and the homeless.
Many were from the Clayton Homes, a public housing complex bounded on one side by an interstate highway and another by Buffalo Bayou, which flooded heavily along with all of Houston's major waterways. Police used boats to evacuate many of the complex's residents and bring them to the convention center in pickup trucks.
D'Ona Spears and Brandon Polson walked with their five children, bags full of belongings, and their 7-year-old Chihuahua, Missy. They decided to leave once the water in the first story of their home reached their knees. Polson said the management at the complex wouldn't open a community building on site that had stayed dry as the apartments around it were flooding.
"As soon as you step out, a lot of cars are in the water," Spears said.
Alex Cantu Jr. rode out the storm underneath a bus shelter. Cantu, 50, said Sunday that he was waiting for a bus to the Salvation Army shelter where he lives, but buses were canceled. The flooding made it too dangerous for his brother to pick him up. So he and a few other people slept in the bus shelter.
"I was soaked cold," he said.
On Sunday morning, his brother told him he could go to the convention center, where he hoped to stay through the duration of the storm.
"I don't know how long they're going to let people stay," he said, a white towel draped around his shoulders. "My brother said it would be over Wednesday."
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Several people told The Associated Press that in hindsight, they wished they had left Houston beforehand. Before Harvey hit, local officials pushed back against Texas Gov. Greg Abbott's suggestion that people in Houston should leave and did not order a voluntary or mandatory evacuation.
Houston Mayor Sylvester Turner stood by that decision Sunday, saying an evacuation would have put many people on roads that eventually flooded and endangered more lives than having residents stay in their homes.
But Desiree Mallard disagreed. As she carried her nearly 2-year-old son in her arms and waited to enter the convention hall, Mallard said she saw on the news not to leave, and so she didn't.
She escaped her apartment by floating her son on an air mattress through floodwaters.
"I could have [left], if I would have known it was going to be this bad, but I didn't know," Mallard said. "And then when it got bad, they said, 'It's too late to evacuate.'"
Walking into the shelter holding his son's hand, William Cain gave a small laugh when a reporter asked if he wished he had evacuated.
"That's a no-brainer, brother," Cain said.