PHOTO GALLERY

1 year after the BP oil spill disaster: A day of remembrance dawns on the Gulf Coast

Courtney Kemp, widow of Roy Wyatt Kemp, 27, who died in the Deepwater Horizon oil rig explosion, holds her daughers Kaylee Kemp, 3, and Madisson Kemp, 9 months, in Jonesville, La., in this Nov. 11, 2010 file photo.

ASSOCIATED PRESS

A shrimp boat uses booms to collect oil in the waters of Chandeleur Sound, La., in this May 5, 2010 file picture/ An April 20, 2010, explosion at the BP Deepwater Horizon offshore platform killed 11 men, and the subsequent leak released an estimated 172 million gallons of petroleum into the Gulf of Mexico.

NEW ORLEANS -- Relatives of some of the 11 men who died aboard the Deepwater Horizon oil rig are flying over the Gulf of Mexico on Wednesday, back to the epicenter of the worst offshore oil spill in the nation's history.

Meanwhile, on land, vigils were scheduled in Louisiana, Mississippi, Alabama and Florida to mark the spill.

On the night of April 20, 2010, the Deepwater Horizon, a rig owned by Transocean Ltd., burst into flames after drilling a well for BP PLC, killing 11 workers on or near the drilling floor. The rest of the crew evacuated, but two days later the rig toppled into the Gulf and sank to the sea floor. The bodies were never recovered.

Over the next 85 days, 206 million gallons of oil -- 19 times more than the Exxon Valdez -- spilled spewed from the well. In response, the nation commandeered the largest offshore fleet of vessels since D-Day, and BP spent billions of dollars to clean up the mess, saving itself from collapse.

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"I can't believe tomorrow has been one year because it seems like everything just happened," Courtney Kemp, whose husband Roy Wyatt Kemp was killed on the rig, wrote on her Facebook page Tuesday. "I have learned a lot of things through all of this but the most important is to live each day as if it were your last ... what matters is if you truly live."

Natalie Roshto, whose husband Shane Roshto also died on the rig, posted a message on Courtney Kemp's Facebook page on Tuesday evening: "Can't believe it's been a year.. It has brought a lot of tears and a great friendship I'm Soooo thankful for.. We are a strong force together!! Love u sista."

In a statement, President Barack Obama paid tribute to those killed in the blast and thanked the thousands of responders who "worked tirelessly to mitigate the worst impacts" of the oil spill.

"But we also keep a watchful eye on the continuing and important work required to ensure that the Gulf Coast recovers stronger than before," Obama said in the statement.

Transocean invited up to three members of each family to attend the flyover. They were expected to circle the site a few times in a helicopter, though there is no visible marker identifying where their loved ones perished. At the bottom of the sea, 11 stars were imprinted on the well's final cap.

Several families said they didn't want to go on the flyover, and Transocean didn't allow media.

At a solemn candle-lit ceremony facing New Orleans' cathedral in Jackson Square shortly after sunrise, environmentalists and religious leaders joined to remember the perished rig workers and call on the nation to take the steps to prevent another environmental catastrophe. The ceremony organized by the Sierra Club attracted only a handful of attendees, underscoring the point of a rabbi who addressed the group.

Courtney Kemp, widow of Roy Wyatt Kemp, 27, who died in the Deepwater Horizon oil rig explosion, holds her daughers Kaylee Kemp, 3, and Madisson Kemp, 9 months, in Jonesville, La., in this Nov. 11, 2010 file photo.

"Our souls are slumbering in moral indifference," said Rabbi Edward Cohn of the Temple Sinai in New Orleans. "People quite rightly are asking: How and when, and by whose insistence and stubborn support, will the public's mind be refocused upon what happened in the Gulf?"

Elsewhere around the world, BP employees were observing a minute of silence Wednesday.

BP chief executive Bob Dudley posted a message on the company's website Wednesday that said, in part: "We are committed to meet our obligations to those affected by this tragedy and we will continue our work to strengthen safety and risk management across BP. But most of all today, we remember 11 fellow workers and we deeply regret the loss of their lives."

The solemn ceremonies underscore the delicate healing that is only now taking shape. Oil still occasionally rolls up on beaches in the form of tar balls, and fishermen face an uncertain future.

Louis and Audrey Neal of Pass Christian, Miss., who make their living from crabbing, said it's gotten so bad since the spill that they're contemplating divorce and facing foreclosure.

"I don't see any daylight at the end of this tunnel. I don't see any hope at all. We thought we'd see hope after a year, but there's nothing," Audrey Neal said.

"We ain't making no money. There's no crabs," said Louis Neal, a lifelong crabber.

Commercial fisherman Ted Petrie picks through a pile of shrimp on his boat in Grand Isle, La., Wednesday, April 20, 2011. Petrie took a job helping with Deepwater Horizon oil spill response efforts in order to make ends meet when local waters were closed to fishing. A year after the spill began, he wonders about its long term effects on marine life and is apprehensive about his odds for success in future shrimp seasons.

"I'm in the worst shape I've ever been in my whole damn life. I'm about to lose my whole family," he said. "I can't even pay the loans I have out there. That's how bad it's gotten."

His wife said the financial hit was only part of the past year's toll. "Our lives are forever changed," she said. "Our marriage, our children, it's all gotten 100 percent worse."

She said the couple received about $53,000 from BP early on, but that was just enough money to cover three months of debt. They haven't received a dime from an administrator handing out compensation from a $20 billion fund set up by BP, they said.

Still, it's not all so bleak.

Traffic jams on the narrow coastal roads of Alabama, crowded seafood restaurants in Florida and families vacationing along the Louisiana coast attest to the fact that familiar routines are returning, albeit slowly.

"We used to fuss about that," said Ike Williams, referring to the heavy traffic headed for the water in Gulf Shores, Ala., where he rents chairs and umbrellas to beachgoers. "But it was such a welcome sight."

Many questions still linger: Will the fishing industry recover? Will the environment bounce back completely? Will an oil-hungry public ever accept more deepwater drilling?

Most scientists agree the effects "were not as severe as many had predicted," said Christopher D'Elia, dean at the School of the Coast and Environment at Louisiana State University. "People had said this was an ecological Armageddon, and that did not come to pass."

But biologists are still concerned about the spill's long-term effect on marine life.

In this July 12, 2010, image from video made available by BP PLC, oil flows out of the top of the transition spool, which was placed into the gushing wellhead and will house the new containment cap, at the site of the Deepwater Horizon oil spill in the Gulf of Mexico.

"There are these cascading effects," D'Elia said. "It could be accumulation of toxins in the food chain, or changes in the food web. Some species might dominate."

Meanwhile, accumulated oil is believed to lie on the bottom of the Gulf, and it still shows up as a thick, gooey black crust along miles of Louisiana's marshy shoreline. Scientists have begun to notice that the land in many places is eroding.

For example, on Cat Island, a patch of land where pelicans and reddish egrets nest among the black mangroves, Associated Press photographs taken a year ago compared with those taken recently show visible loss of land and a lack of vegetation.

On a tour of the wetlands Tuesday, Robert Barham, Louisiana's wildlife secretary, showed reporters the lingering damage.

Roseau cane is growing again where it was cut away during early cleanup efforts, but Barham said the 3- to 4-foot-high stalks should be a lush green. Instead, they were pale green and brown.

"It's because of oil in the root system," Barham said. He put his hand into the dirt and pulled up mud saturated with oil. Tossing the sludge into nearby water, it released a rainbow-colored sheen.

Barham complained that BP had not done enough to clean the area. "What they've done thus far is not working."

A cross with the words "promises made," referring to promises made by BP PLC and government officials responding to the Deepwater Horizon oil spill, stands in front of a pile of crosses symbolizing things that were impacted by the spill in a front yard in Grand Isle, La., on April 20, 2011.

In the remote Louisiana marsh, there's still yellow boom in places not to keep oil out but to keep the tides from carrying oil to untouched areas.

Confidence in Louisiana's seafood is eroding, too.

"Where I'm fishing it all looks pretty much the same," said Glen Swift, a 62-year-old fisherman in Buras. He's catching catfish and gar in the lower Mississippi River again. That's not the problem.

"I can't sell my fish," he said. "The market's no good."

But the BP spill has faded from the headlines, overtaken by the tsunami and nuclear disaster in Japan, unrest in the Middle East and political clashes in Washington.

"Nationally, BP seems like a dim and distant memory," said Douglas Brinkley, a Rice University historian. But the accident will have long-lasting influence on environmental history, he said.