Antonia Juhasz

“You’ve got to mark this anniversary,” he says. “There’s a lot more that needs to be done.”

April 20, 2010, is a day nobody in the Gulf will forget, particularly those 11 families who lost loved ones when an explosion 50 miles from the Louisiana coast ripped through the Deepwater Horizon rig. For the communities affected, the companies involved, including BP, and the country’s politicians, the 12 months that have followed can be divided into two unequal halves.

The 86 days until the well was capped on July 15 saw BP and Tony Hayward, its then chief executive, strained to almost breaking point, President Barack Obama face his first, major unexpected test and an underwater camera beam images of crude gushing from the broken well into living rooms across the world. While the oil flowed and the scale of the disaster remained unknown, the narrative was frightening enough, and clear enough, to grip the nation.

In the months since, the drama of one villianous, foreign company and its gaffe-prone chief executive has been replaced by a more complex and even more politicised set of responses to how America should react.

“The country has turned away,” says Antonia Juhasz, the author of Black Tide, a new book on the spill. “The one-year anniversary is an opportunity to refocus attention,” she says.

Local attention has never wavered. There’s still plenty of anger in communities along the Gulf and some of it is directed against BP, which was rechristened British Petroleum by an under-fire Obama last summer. The company, which is not marking the event publicly in the Gulf region, now has about 2,000 people working on clean-up efforts compared to 48,000 at the height of the disaster. A year on, the anxiety of fishermen, oystermen and shrimpers is best measured in years, not months. At a meeting earlier this year in New Orleans, their overriding concern was about the effect of the oil, as well as the methods used to disperse it, on the long-term health of their catch. Despite tests giving current hauls the all-clear, anxieties remain. And the National Ocean and Atmospheric Administration estimates that 30pc of the oil that flowed into the Gulf’s waters remains unaccounted for. “We will continue to hear about consequences at the local level,” says Nathan Hultman, an energy expert and director of public policy studies at the University of Maryland.

BP’s retreat from the national glare quickened the moment it handed Ken Feinberg the keys to its $20bn pot for individuals and businesses damaged by the spill. So it’s Feinberg, who was also in charge of handing out compensation to the families of the victims of the Sept 11 attacks, not BP, who is in the crosshairs. The Gulf Coast Claims Facility, as the fund is officially known, said this week that it’s paid out $3.8bn by processing 300,000 of the 857,000 claims submitted. For its part, BP says it has so far spent a total of $17bn on compensation and clean-up efforts.

While the spill has slipped from the focus of the national media – this week will prove an exception – it’s taking centre stage in the courts. And one in particular – the courtroom of judge Carl Barbier of the Eastern District of Louisana. For those wanting to sue BP, Transocean and others involved in the spill, Barbier’s court had to have their suits by today. In a frenzy of filing, thousands have been submitted and a trial date of next February set. The trial will examine Transocean’s claim that its liability stands at no more than $27m and thereby determine the liability of other defendants, including BP. “We’ve been working seven days a week for almost a year,” says Stephen Herman, one of the two lawyers tasked with shepherding the suits through the New Orleans court. Lawyers will be meeting today at court as they refine the legal timetable between now and next February, he says.

But it’s the ongoing criminal investigation that legal experts say is most likely to be worrying BP and the other defendants. After announcing the investigation in June, the Department of Justice (DoJ) last month reorganised the inquiry under the direction of John Buretta, a man who has built his reputation prosecuting mafia families and gangs in New York. Recent reports suggest that the DoJ is considering possible manslaughter charges against executives as well as criminal fines against the companies.

David Uhlmann, who used to run the DoJ’s environmental crimes division and now teaches at the University of Michigan, believes that a decision on charges will come by early next year. The case is “a top priority for the attorney general and the deputy attorney general, and it will be a career-defining case for the investigators and prosecutors.”

The rest of the oil industry will be paying close attention to the outcome. As politicians blasted BP last summer and its share price collapsed, the company’s US rivals held their tongues. The last few months, however, have seen them find their voice and it’s proving a hostile one. In March, Bob Dudley, BP’s new chief executive, told an audience of oil executives in Houston that the Deepwater Horizon explosion should not be dismissed as a ‘Black Swan’ event, and that it held wider lessons for the oil industry. That drew a sharp response from Rex Tillerson, the man who runs ExxonMobil, the world’s biggest energy company. To extrapolate BP’s failings across the industry was, he said, a “real overreach” and “just wrong.” It’s view that has been echoed by James Watson, the chief executive of Chevron.

A year on and the nationwide anger that assailed BP is now more localised. The anniversary also underlines the spill’s limited impact on generating a wider debate about energy usage in the US. “It’s proved a reminder that oil extraction comes with hazards,” says Hultman from the University of Maryland. “I don’t think it’s a turning point.”