Even as the water receded in some areas, it was rising in other communities downstream, sending people fleeing to shelters.
Officials painted a stark picture of the crisis: at least 40,000 homes damaged and 11 people killed in some of the worst flooding in Louisiana history. More than 30,000 people have been rescued since Friday.
More than 110 state highways remained closed Wednesday, along with even more local roadways.
Amid scattered reports of looting, Louisiana Gov. John Bel Edwards said parishes with widespread damage were being placed under curfew as of Tuesday night.
Residents and business owners in the town of Albany repeatedly noted that the area had never flooded before — and flood insurance wasn't required.
As the water receded, people donned surgical masks and began the back-breaking job of ripping out soggy carpet, drywall and insulation. They cleared out spiders and cockroaches that had bubbled up through the sewer grates.
Some businesses already have placed huge garbage bins out front to hold ruined inventory and soggy debris. In residential areas a powerful stench wafts off huge piles of sodden garbage, soaked upholstery and carpets and discarded appliances.
Chris Bankston was with workers mucking out his family-owned auto parts store Wednesday. He said his father opened the business nearly 70 years ago. Water had never gotten within 200 yards of his business until the weekend, he said.
In the town of Sorrento, James Lane was getting to work cleaning his house — something familiar to him from Hurricane Katrina in 2005.
"I can't even think about what to do, just got to go with it as it comes in," Lane said. "We actually lost everything in Katrina, came here 10 years later, lost everything again."Officials have been going house to house to ensure everyone was accounted for. They also searched countless cars caught in the flooding.
"I don't know we have a good handle on the number of people who are missing," the governor said.
For the Baton Rouge area, it was a blow on top of what has already been a tough summer starting with the shooting death of 37-year-old Alton Sterling on July 5. The death of Sterling, a black man, at the hands of two white police officers incited widespread protests in which nearly 200 people were arrested.
Then on July 17, a lone gunman shot and killed three law enforcement officers and wounded three others outside a Baton Rouge convenience store. The suspect, Gavin Long, an Army veteran from Kansas City, Missouri, was himself killed by police. All of the dead officers lived in the area of Denham Springs, a quiet bedroom community across the Amite River from Baton Rouge.
Then the rains hit.
About 68,000 people have signed up for assistance from the Federal Emergency Management Agency, and the number is expected to rise. Twenty parishes were included in the federal disaster declaration.
And help was coming from quarters beyond the federal government.
Performer Taylor Swift told The Associated Press she is donating $1 million to flood relief.
"The fact that so many people in Louisiana have been forced out of their own homes this week is heartbreaking," the 26-year-old said in a statement.
Entertainer Lady Gaga also said she's donating an unspecified amount to flood relief efforts
In Livingston Parish, one of the hardest-hit areas with about 138,000 people, an official estimated that 75 percent of the homes were a total loss.
Officials from Livingston Parish were in Baton Rouge on Tuesday to talk to federal officials about getting temporary housing for their first responders — a sign of the housing crunch likely to come with so many people out of their homes for weeks and perhaps months.
Rivers and creeks were still dangerously bloated south of Baton Rouge as water drained toward the Gulf of Mexico.
Nearly 800 evacuees waited Tuesday in a makeshift Red Cross shelter in Gonzales at the Lamar Dixon Expo Center, a multipurpose facility that has hosted rodeos, car and truck shows and concerts.
Floyd Melancon, 71, and his partner, Judy McGehee, 61, remained in the dark about how much water — if any — their Prairieville home received.
"My neighbor sent me a picture. Water was in the yard. I don't know where it's at right now," Melancon said. "Judy and I think it's come up since then."
In the house for 14 years, the couple lacks flood insurance to cover repairs.
"We weren't in a flood zone. It had never flooded before," McGehee said.
With flood insurance, homeowners are prone to draining savings accounts and relying on federal disaster programs to rebuild and repair.
Insurance Commissioner Jim Donelon said in hard-hit Baton Rouge only 12 percent of residences are covered by flood insurance, and 14 percent in Lafayette — what he called "shocking."
The governor said he is worried about "battle fatigue" setting in as rescuers and residents deal with day upon day of stress.
The trauma was evident among people who went back to their homes.
David Key used a small boat to get to his house in Prairieville and said it had taken on 5 inches of "muddy, nasty bayou water." There were fish and thousands of spiders, and mold had started to grow.
"I'm not going to lie, I cried uncontrollably," he said. "But you have to push forward and make it through. Like everybody says, you still have your family."
Kunzelman and Deslatte reported from Baton Rouge. Joshua Replogle in Sorrento contributed to this report.