STORY HIGHLIGHTS
- Port at Mobile prepares for vessel's return
- U.S. agencies join engine room fire investigation
- Conditions are improving and activities are planned aboard the stricken ship, Carnival says
- Carnival says the cruise ship will dock Thursday afternoon
(CNN) -- Ewwwww.
That about sums up how people are describing conditions aboard the Carnival Triumph on Tuesday as tugboats slowly drag the stricken cruise ship toward Alabama -- and freedom for its 3,143 passengers.
Some on the ship reported sewage sloshing around in hallways, flooded rooms and trouble getting enough to eat after a fire in the ship's engine room Sunday left it drifting in the Gulf of Mexico. Passengers dragged their mattresses onto the ship's open deck to stay cool and get away from the nasty smells inside.
"The odor is so bad, people are getting sick and they're throwing up everywhere," said Brent Nutt, whose wife is aboard the ship.
But not all passengers share the same dire view of the situation.
A poster on the cruising forum cruisecritic.com said her sister reported passengers have enough food and are "enjoying the extended vacation."
The fire is at least the second problem for the ship since late January, when it had an issue with its propulsion system, according to a notice posted to Carnival senior cruise director John Heald's website.
The company also recently repaired one of Triumph's alternators, the company said Tuesday.
However, there's no evidence the alternator problem and the fire are linked, cruise line spokesman Vance Gulliksen said.
Sunday's fire came as the Triumph steamed about 150 miles off Mexico's Yucatan Peninsula on the way back to Galveston, Texas. The ship was on the third day of a four-day cruise.
"We all woke up and panicked," passenger Donna Gutzman told CNN affiliate KPRC. "A couple other alarms went off and we started seeing smoke."
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Triumph's automatic fire extinguishing system kicked in and soon contained the flames, and no injuries were reported, Carnival said.
But the fire knocked out the ship's propulsion system and left the vessel slowly drifting in the Gulf until a second tugboat arrived Tuesday, joining one that had come earlier. The U.S. Coast Guard cutter Vigorous is also sailing nearby to provide assistance if necessary.
The tugboats are towing the Triumph toward Mobile at a rate of 5 mph to 8 mph, Vigorous Cmdr. Greg Magee told CNN Tuesday.
Gulliksen said Carnival expects the ship to arrive in Mobile on Thursday afternoon.
"The tugs on scene have been doing a great job of keeping it moving north," said Magee, who added that his crew has not gone onto the Triumph to assess what's happening on board.
Carnival scheduled a news conference Tuesday evening to update reporters on the situation aboard the ship.
The cruise line said the ship was listing at 2 degrees, an improvement from a previous 4.5-degrees reading. Winds are causing the list, it said.
Technicians aboard the ship were trying to restore power and provide more onboard facilities, Gulliksen said.
Passenger Ann Barlow said the staff on the Triumph was doing a good job, but that flooded rooms, hot, humid conditions, long lines for food and overwhelming odors were making things tough for passengers.
"It's disgusting. It's the worst thing ever," she told CNN Monday.
Barlow's husband, Toby, said she told him there was "sewage running down the walls and floors" with passengers being asked to defecate in bags and urinate in showers due to the lack of functioning toilets. The air conditioning is also out.
But things were getting better, according to Nutt and Gulliksen.
Nutt said his wife tells him the boat isn't listing as much as it was Sunday, when she called worried she was going to die.
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Gulliksen said Tuesday that cabins have running water -- cold only -- and some toilets are working in public areas and some cabins. The ship's poolside restaurant was open until 10 p.m. Monday night and reopened again at 7 a.m. Tuesday.
And, he said, "Carnival Triumph's entertainment staff has planned various activities to keep guests entertained."
There are 1,086 crew members on the ship.
Carnival has also brought meals aboard from two other cruise ships, the cruise line said Monday. Earlier, Carnival said in a statement that hot coffee was available, among other options.
"All our guests are safe, and we're doing everything we can to make them as comfortable as possible," Carnival CEO Gerry Cahill said Monday night. "We're terribly sorry for the inconvenience, discomfort and frustration our guests are feeling."
The Coast Guard and the National Transportation Safety Board launched an investigation into the cause of the engine room fire. Because the Carnival Triumph is a Bahamian-flagged vessel, the Bahamas Maritime Authority is the primary investigative agency.
Carnival initially planned to tow the ship to Progreso, Mexico, but strong currents that had pushed it 90 miles north by Monday night prompted the decision to move the ship to Mobile instead. The change also made it easier on the 900 passengers who don't have passports, the cruise line said.
Passengers will get a free flight home, a full refund for their trip and most expenses aboard, and a credit for another cruise, Carnival said.
Sheila Gurganus, general manager of the Mobile cruise terminal, said medical personnel will be on hand to help anyone in need. Other agencies will help expedite the passengers' return home.
The incident has forced Carnival to cancel the ship's next two departures, refund bookings for those trips and offer those passengers discounts on future cruises.
In 2010, the Carnival's cruise ship Splendor lost power after an engine room fire, leaving it drifting off the Pacific coast of Mexico. The USS Ronald Reagan ferried 60,000 pounds of supplies for the ship's passengers and crew as the ship was towed to San Diego.
Richard Burke, chairman of the engineering faculty at the State University of New York's Maritime College, told CNN he had "no reason to believe that Carnival in any way is not a first-class operator. Nor do I believe that their ships are not good ships. I think they are just being unlucky right now."
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CNN's Joe Sutton, Dave Alsup, Mike Ahlers, Sandra Endo, Chuck Johnston, Esprit Smith, Greg Botelho and Marnie Hunter contributed to this report.