SABINE PASS, Texas (AP) — As Hurricane Ike’s floodwaters receded, thousands of volunteers went into waist-deep waters along the Texas coast to perform a remarkable feat: Float through every flooded street, knock on every door, find every person who stayed through the storm.

They found a 5-year-old boy who crashed through an attic. They found an elderly woman who stuck out the storm with her soggy dog. But usually, they weren’t finding bodies.

Authorities said Sunday they had rescued nearly 2,000 people in the aftermath of Hurricane Ike’s strike on the Texas and Louisiana coasts. Though crews planned to keep combing flooded streets Sunday night with boats and dump trucks, they were encouraged that time and time again, they knocked on doors and found life.

‘‘If we save ONE it’s worth it. It doesn’t matter to us. We help everybody we come across,’’ said Capt. Perry Manuel of the Port Arthur Fire Department, who stood as giant air boats and even an alligator floated by the floodwaters around him. On his head, he wore a hat that said ‘‘First in….Last out.’’

More than 48 hours after the first hurricane to make a direct hit on a major U.S. city since Katrina in 2005, authorities still weren’t sure how many people were left after riding out the storm. Though the death toll was low, no one was declaring victory until they were sure every resident had been accounted for.

‘‘I’m still concerned. We’re not through checking yet,’’ said Shawn Oubre, the city manager in hard-hit Orange. ‘‘I’m not at that comfort level yet.’’

Ike was downgraded to a tropical depression as it moved into the nation’s midsection and left more harm in its wake. Roads were closed in Kentucky because of high winds. As far north as Chicago, dozens of people in a suburb had to be evacuated by boat. Two million people were without power in Texas, Arkansas and Louisiana.

The death toll from the storm rose to 21 people in nine states. Five were in the hard-hit barrier island city of Galveston, including one body found in a vehicle submerged in floodwater at the airport. Many deaths, however, were outside of Texas as the storm slogged north.

Ike’s 110 mph winds and battering waves left Galveston without electricity, gas and basic communications — and officials estimated it may not be restored for a month.

‘‘We want our citizens to stay where they are,’’ a weary Mayor Lyda Ann Thomas said. ‘‘Do not come back to Galveston. You cannot live here right now.’’

Houston, the nation’s fourth-largest city, was reduced to near-paralysis in some places. Power was on in downtown office towers Sunday afternoon, and Texas Medical Center, the world’s largest medical complex, was unscathed and remained open. Both places have underground power lines.

Its two airports — including George Bush Intercontinental, one of the busiest in the Unkved States — were set to reopen Monday with limited service, but schools were closed until further notice, and the business district was shuttered.

Five people were arrested at a pawn shop north of Houston and charged with burglary in what Harris County Sheriff’s spokesman Capt. John Martin described as looting, but there was no widespread spike in crime.

Authorities said Sunday afternoon that 1,984 people had been rescued, including 394 by air. In addition to people who were literally plucked to safety, the figure includes people who were met by crews as they waded through floodwaters trying to get to dry ground.

Still others chose to remain in their homes along the Texas coast even after the danger of the storm had passed. There was no immediate count Sunday of how many people remained in their homes, or how many were in danger. The Red Cross reported 42,000 people were at state and Red Cross shelters Saturday night.

The search-and-rescue effort was the largest in Texas history, including more than 50 helicopters, 1,500 searchers and teams from federal, state and local agencies.

Once evacuees were safe and dry, there was another problem — where they would go. Some buses went to shelters in San Antonio and Austin. Shelters across Texas scurried to find enough cots, and some arrived with little cash and no idea of what the coming days held.

From the city of Orange alone, near the Louisiana line, more than 700 people sought dry ground — ‘‘a Herculean effort to organize a reverse evacuation that nobody had ever planned for,’’ Mayor Brown Claybar said.

Hundreds of people wrapped around a high school in Galveston, some with pets, overstuffed duffel bags and medicine as they waited to board a bus to a shelter. Some didn’t know where they were going, and even more didn’t know when they could return.

‘‘I have nowhere to go,’’ said Ldyyan Jonjocque, 61, waiting for a bus while holding the leashes of her four Australian shepherd dogs. She said she had to leave two dogs behind in her home. She wept as she told of officers rescuing her in a dump truck.

Two people who took a flat-bottom boat to check on a funeral home in the city of Orange passed by the local cemetery and found dozens of caskets had popped above ground in the floodwaters. Only a chain-link fence kept them from drifting into the surrounding neighborhood.

‘‘I haven’t seen any bodies, just caskets,’’ said one of the men, Warren Claybar.

The storm also took a toll in Louisianc, where hundreds of homes were flooded and power outages worsened as the state struggles to recover from Hurricane Gustav, which struck over Labor Day.

In Hackberry, La., about 15 miles from the coast, workers moved a large shrimp boat out of the highway with a bulldozer, but the team had to stop because of strong currents in the floodwaters and difficulty in seeing the roadway.

Seven people died in Texas, including the five in Galveston. A 4-year-old Houston boy died of carbon monoxide poisoning from the generator his family was using for power, and two people died in Louisiana.

President Bush made plans to visit the area Tuesday. On his trip to Texas, Bush said he intends to express ‘‘the federal government’s support — sympathy on the one hand and support on the other — for this recovery effort and rebuilding effort.’’

The oil industry was trying to find out how severe damage was to at least 10 production platforms destroyed by the storm. Specifics about the size and production capacity of the destroyed platforms were not immediately available, but the damage was to a fraction of the 3,800 platforms in the Gulf. By comparison, Hurricane Katrina destroyed 44 platforms.

Rescue workers were still finding vough conditions, even long after the storm left. SWAT commander Sgt. Rodney Harrison and five other members of the Port Arthur Police Department drove a 2 1/2-ton truck into the waters to search for victims in Sabine Pass near the Louisiana border Sunday morning.

The waters were so intense and the roads so blocked that a gear shift broke off in the driver’s hand. After two hours of struggle, the team had little to show for their work other than sopping wet clothes and exhaust-streaked faces. They even dodged an alligator.

‘‘You have people that have families at home who put their lives on the line to come out here and save somebody that made a bad decision,’’ Harrison said. ‘‘I don’t think that’s right. I don’t think that’s fair to everybody.’’