They live in limbo, not knowing when -- or if -- they'll be able to return to their homes or schools.
CNN talked to people staying in shelters in Baton Rouge. Here are a few of their stories.
Ashlee and Danin Albarado were in Memphis when the flooding started in their hometown of Baton Rouge, but the rising water in Ascension Parish wasn't their biggest worry. They were at St. Jude Children's Research Hospital where their daughter Jill was having surgery for bone cancer.
The good news is that the 9-year-old girl's operation on Monday successfully removed the tumor on her femur and her leg was saved.
The bad news: The Albarados and many of their friends and relatives have lost most, if not all, of their property to the deluge.
"We're in need of everything back home, we're in need of essentials," Ashlee Albarado told CNN's "New Day" from Memphis Saturday. "We're in need of socks and clothes and shoes and pillows and blankets, you name it."
Being at St. Jude's with a critically ill daughter puts a different perspective on the flood, but Ashlee doesn't minimize the loss of property. She has busied herself organizing donations for back home by working with the hospital staff to collect them.
And she knows that when they get home, they'll have to start rebuilding their material lives. Much of their property was in a storage unit because they were in the process of moving to a new house. The storage unit went completely under water, she said, like many of the homes of their neighbors and relatives. Those people are starting over from scratch.
"I am sitting in the ICU in Memphis, Tennessee, with my daughter today," she wrote in an email Friday. "She is and always will be my number one priority. However, our home town is HURTING."
Fortunately, the Albarados' new house escaped the floodwaters, but friends have reported that it is full of ants. "Just ants, looking for dry land," she said.
After cancer, medical bills and now ruined property, ants were an issue she thought they could deal with. The family set up a GoFundMe page, "Help for Jill," to raise money for expenses.
Two siblings try to stay busy
Not knowing is the new normal for Lionel and Crystal Lee, an eighth-grade boy and a seventh-grade girl.
They fled from their home with their family when water started coming up the driveway. Their father went to see what was left of their house Thursday and salvaged only a few things. Their only certainty: "We ain't going back to that house," Lionel says.
Staying at the shelter felt weird at first, they said. They go to bed at 8 or 9 o'clock in a big room with hundreds of others, wake up in the morning, make their beds and take a shower. They read books and try to keep busy. They try to maintain a semblance of normalcy when everything they know was pulled from beneath them.
School is another unanswered question. They'd been to classes two days when the water came rushing into town. They have no idea when they'll sit down in another classroom, or where.
"We're kind of used to it now," Crystal said.
Mother with 6 kids wonders what's next
Sheneka Ealy and her six children left their house when the rescue boats arrived.
"I see what the people went through in Katrina," she said. "It came up so fast, you couldn't get nothing to get out. Cars were under, trucks were under."
She said her children are doing OK in the shelter, except for the one with special needs. But uncertainty hangs over everything.
"Where you go from here, you don't know," she said. "Hopefully soon I'll be able to go to my house, but what am I going to be able to go home to? No beds. No television, no food. If you can go home, what could you go home to?"
Fate of school worries teen
Chad Taylor was supposed to start his senior year of high school Monday, but the flooding came first.
He doesn't know if the school building was damaged. He was told "it's pretty bad."
"I've never been through anything like this," Taylor said. "I only see stuff like that in movies."
At the shelter, he comforts his younger siblings and tells them everything will work out. He just wants to get back to school so he can play basketball and study his favorite subject, English.
"Hopefully soon," he said. "I love school."