Updated 11:46 p.m. ET
No remedy in sight, President Barack Obama warned of a "massive and potentially unprecedented environmental disaster" as a badly damaged oil well in the Gulf of Mexico spewed a widening and deadly slick toward delicate wetlands and wildlife. He said it could take many days to stop.
Obama on Sunday flew to southern Louisiana to inspect forces arrayed against the oil gusher as Cabinet members described the situation as grave and insisted the administration was doing everything it could. Then he took a 15-mile helicopter ride over marshlands and estuaries to a coastal area, but high winds prevented the craft from going out to the 30-mile oil slick caused by as much as 210,000 gallons of crude gushing into the Gulf each day.
Mindful of the political damage suffered by President George W. Bush for a slow response after Hurricane Katrina ravaged the same region, Obama defended his administration's actions, saying it had been preparing for the worst from "day one" even as it had "hoped for the best."
The spill threatened not only the environment but also the region's abundant fishing industry, which Obama called "the heartbeat of the region's economic life." As of now, it appeared little could be done in the short term to stem the oil flow, which was also drifting toward the beaches of neighboring Mississippi and farther east along the Florida Panhandle. Obama said the slick was 9 miles (14 kilometers) off the coast of southeastern Louisiana.
Those who live and work in the region braced for the economic impact on fishing and tourism. In front of a cabin and RV park along Louisiana Highway 23, was a plywood sign pleading: "Obama Send Help!!!!"
BP Chairman Lamar McKay raised faint hope that the spill might be stopped more quickly by lowering a hastily manufactured dome to the ruptured wellhead a mile deep in the next six to eight days, containing the oil and then pumping it to the surface. Such a procedure has been used in some well blowouts but never at the mile-deep waters of this disaster.
The leaking well was not only an ecological disaster but a potential political hazard, as well, depending on how the public judges the Obama administration's response. In 2005, President George W. Bush stumbled in dealing with Hurricane Katrina in the Gulf and left the impression of a president distant from immense suffering. His presidency never recovered.
An investigation is under way into the cause of the April 20 well explosion and, depending on its outcome, questions may be raised about whether federal regulation of offshore rigs operating in extremely deep waters is sufficient and whether the government is requiring the best available technology to shut off such wells in event of a blowout.
The president vowed that his administration, while doing all it could to mitigate the disaster, would require well owner BP America to bear all costs. "Your government will do whatever it takes for as long as it takes to stop this crisis," he said.
"BP is responsible for this leak. BP will be paying the bill," Obama said after a Coast Guard briefing in Venice, a Gulf Coast community serving as a staging area for the response. He stood before cameras in a heavy rain, water dripping from his face.
The president also stopped to talk with six local fishermen and said the challenge is "How do we plug this hole?" After that, he said, protecting the estuaries would be the next priority.
"We're going to do everything in our power to protect our natural resources, compensate those who have been harmed, rebuild what has been damaged and help this region persevere like it has done so many times before," Obama said.
Arriving in New Orleans, the president shunned helicopter travel because of a threat of tornadoes and drove to Venice to tour a close-to-the-water staging area where the government and BP were trying to keep the slick from causing even more damage.
Homeland Security Secretary Janet Napolitano said any comparison between the ruptured BP oil well and Katrina was "a total mischaracterization" and that the government had taken an "all hands on deck" approach from the beginning.
Administration officials have been at pains to explain that Obama's late March decision to expand offshore oil exploration could be altered as a result of the spill and that stricter safety rules would doubtless be written into leases.
Earlier on Sunday, the White House pledged to do everything "humanly possible" to address the Gulf Coast oil spill as Obama headed to the region for a firsthand assessment of the environmental disaster.
He heard from advisers about progress on lowering a device that would capture oil flowing from the underwater well off Louisiana, and about shooting chemicals deep near the well in hopes of breaking up the oil before it can reach the surface.
"That's something that hasn't been tried before, and I think it goes to show that we are trying everything that we know and even some things that haven't been tried before," White House spokesman Robert Gibbs told reporters during the flight from Washington.
The leaking oil well is not only an ecological catastrophe but a potential political hazard, as well, depending on how the public judges the Obama administration's response. Then-President George W. Bush stumbled in dealing with Hurricane Katrina in the Gulf in 2005, leaving the impression of a president distant from the immense suffering. His presidency never recovered.
A month ago, President Obama said he was ready to expand drilling in some parts of the central and south Atlantic and eastern Gulf areas. On Friday, in a largely symbolic gesture, Mr. Obama promised that no new offshore oil drilling leases will be issued unless rigs have new safeguards to prevent a repeat of the Gulf spill.
Homeland Security Secretary Janet Napolitano said any comparison between the ruptured BP oil well and Katrina was "a total mischaracterization" and that the government has taken an "all hands on deck."
President Obama was met at the airport by Louisiana Gov. Bobby Jindal, then left in a motorcade for Venice, about 75 miles to the southeast and the site of a staging area close to the water.
The president received a briefing from his homeland security adviser, John Brennan, and his energy adviser, Carol Browner, on BP's plans to lower a dome that would cap the well at the sea floor and hopefully halt the flow of an estimated 5,000 barrels a day into Gulf waters.
BP's chairman, Lamar McKay, said Sunday he expects the 40-foot high dome structure to be ready to be deployed in six to eight days. Such domes have been used in other well blowout incidents, but never in such deep waters. The oil would be captured and funneled to the surface.
The advisers also told the president of some preliminary success by BP to shoot oil dispersant chemicals deep into the water, near the source of the leak. An initial test showed signs of success and a second test was planned for Sunday.
The threats of further spread of the oil slick, promoted the National Oceanic and Atmospheric Administration to close for at least 10 days, commercial and recreational fishing from Louisiana to parts of the Florida Panhandle.
The Coast Guard estimated that at least 1.6 million gallons of oil have spilled since the April 20 explosion that killed 11 workers on an offshore rig. In the Exxon Valdez disaster, an oil tanker spilled 11 million gallons off Alaska's shores in 1989.
Efforts to stem the flow from the ruptured well on the sea floor and remove oil from the surface by skimming it, burning it or by dispersing it with chemicals continued with little success. Adding to the gloomy outlook were warnings from experts that an uncontrolled gusher could create a nightmare scenario if the Gulf Stream current carries it toward the Atlantic.
Mr. Obama has relied on reports from agency chiefs and Coast Guard officials since the magnitude of the spill became clear late Wednesday. Aides report he's been getting regular updates.
Napolitano, Interior Secretary Ken Salazar and the administration's point man on the disaster, the commandant of the Coast Guard, Adm. Thad Allen, made the rounds of the Sunday talk shows to defend the federal response.
There is growing criticism that the government and oil company BP PLC should have done more to stave off the disaster, which cast a pall over the fragile environment and the region's economy, still recovering from the devastation of 2005's Hurricane Katrina.
"These people, we've been beaten down, disaster after disaster," said Matt O'Brien of Venice, whose fledgling wholesale shrimp dock business is under threat from the spill.
"They've all got a long stare in their eye," he said. "They come asking me what I think's going to happen. I ain't got no answers for them. I ain't got no answers for my investors. I ain't got no answers."
He wasn't alone. As the spill surged toward disastrous proportions, critical questions lingered: Who created the conditions that caused the gusher? Did BP and the government react robustly enough in its early days? And, most important, how can it be stopped before the damage gets worse?
The Coast Guard conceded Saturday that it's nearly impossible to know how much oil has gushed since the April 20 rig explosion, after saying earlier it was at least 1.6 million gallons - equivalent to about 2 1/2 Olympic-sized swimming pools. The blast killed 11 workers and threatened beaches, fragile marshes and marine mammals, along with fishing grounds that are among the world's most productive.
Even at that rate, the spill should eclipse the 1989 Exxon Valdez incident as the worst U.S. oil disaster in history in a matter of weeks. But a growing number of experts warned that the situation may already be much worse.
The oil slick over the water's surface appeared to triple in size over the past two days, which could indicate an increase in the rate that oil is spewing from the well, according to one analysis of images collected from satellites and reviewed by the University of Miami. While it's hard to judge the volume of oil by satellite because of depth, it does show an indication of change in growth, experts said.
"The spill and the spreading is getting so much faster and expanding much quicker than they estimated," said Hans Graber, executive director of the university's Center for Southeastern Tropical Advanced Remote Sensing. "Clearly, in the last couple of days, there was a big change in the size."
Doug Suttles, BP's chief operating officer for exploration and production, said it was impossible to know just how much oil was gushing from the well, but said the company and federal officials were preparing for the worst-case scenario.
In an exploration plan and environmental impact analysis filed with the federal government in February 2009, BP said it had the capability to handle a "worst-case scenario" at the Deepwater Horizon site, which the document described as a leak of 162,000 barrels per day from an uncontrolled blowout - 6.8 million gallons each day.
Oil industry experts and officials are reluctant to describe what, exactly, a worst-case scenario would look like - but if the oil gets into the Gulf Stream and carries it to the beaches of Florida, it stands to be an environmental and economic disaster of epic proportions.
The Deepwater Horizon well is at the end of one branch of the Gulf Stream, the famed warm-water current that flows from the Gulf of Mexico to the North Atlantic. Several experts said that if the oil enters the stream, it would flow around the southern tip of Florida and up the eastern seaboard.
"It will be on the East Coast of Florida in almost no time," Graber said. "I don't think we can prevent that. It's more of a question of when rather than if."
At the joint command center run by the government and BP near New Orleans, a Coast Guard spokesman maintained Saturday that the leakage remained around 5,000 barrels, or 200,000 gallons, per day.
But Coast Guard Adm. Thad Allen, appointed Saturday by President Obama to lead the government's oil spill response, said no one could pinpoint how much oil is leaking from the ruptured well because it is about a mile underwater.
"And, in fact, any exact estimation of what's flowing out of those pipes down there is probably impossible at this time due to the depth of the water and our ability to try and assess that from remotely operated vehicles and video," Allen said during a conference call.
The Coast Guard's Allen said Saturday that a test of new technology used to reduce the amount of oil rising to the surface seemed to be successful.
During the test Friday, an underwater robot shot a chemical meant to break down the oil at the site of the leak rather than spraying it on the surface from boats or planes, where the compound can miss the oil slick.
From land, the scope of the crisis was difficult to see. As of Saturday afternoon, only a light sheen of oil had washed ashore in some places.
The real threat lurked offshore in a swelling, churning slick of dense, rust-colored oil the size of Puerto Rico. From the endless salt marshes of Louisiana to the white-sand beaches of Florida, there is uncertainty and frustration over how the crisis got to this point and what will unfold in the coming days, weeks and months.
The concerns are both environmental and economic. The fishing industry is worried that marine life will die - and that no one will want to buy products from contaminated water anyway. Tourism officials are worried that vacationers won't want to visit oil-tainted beaches. And environmentalists are worried about how the oil will affect the countless birds, coral and mammals in and near the Gulf.
"We know they are out there" said Meghan Calhoun, a spokeswoman from the Audubon Aquarium of the Americas in New Orleans. "Unfortunately the weather has been too bad for the Coast Guard and NOAA to get out there and look for animals for us."
Fishermen and boaters want to help contain the oil. But on Saturday, they were again hampered by high winds and rough waves that splashed over the miles of orange and yellow inflatable booms strung along the coast, rendering them largely ineffective. Some coastal Louisiana residents complained that BP, which owns the rig, was hampering mitigation efforts.
"I don't know what they are waiting on," said 57-year-old Raymond Schmitt, in Venice preparing his boat to take a French television crew on a tour. He didn't think conditions were dangerous. "No, I'm not happy with the protection, but I'm sure the oil company is saving money."
As bad as the oil spill looks on the surface, it may be only half the problem, said University of California Berkeley engineering professor Robert Bea, who serves on a National Academy of Engineering panel on oil pipeline safety.
"There's an equal amount that could be subsurface too," said Bea. And that oil below the surface "is damn near impossible to track."
Louisiana State University professor Ed Overton, who heads a federal chemical hazard assessment team for oil spills, worries about a total collapse of the pipe inserted into the well. If that happens, there would be no warning and the resulting gusher could be even more devastating because regulating flow would then be impossible.
"When these things go, they go KABOOM," he said. "If this thing does collapse, we've got a big, big blow."
BP has not said how much oil is beneath the Gulf seabed Deepwater Horizon was tapping, but a company official speaking on condition of anonymity because he was not authorized to discuss the volume of reserves, confirmed reports that it was tens of millions of barrels - a frightening prospect to many.
Louisiana Gov. Bobby Jindal said that he has asked both BP and the Coast Guard for detailed plans on how to protect the coast.
"We still haven't gotten those plans," said Jindal. "We're going to fully demand that BP pay for the cleanup activities. We're confident that at the end of the day BP will cover those costs."
In a statement late Saturday, a Coast Guard spokesman said the governor's office helped develop the plans that Jindal referred to.
Capt. Ron LaBrec said federal and company officials had been working closely with the governor's office "since day one" to implement contingency "which were developed in coordination with state and local leadership before this incident began."
Obama has halted any new offshore drilling projects unless rigs have new safeguards to prevent another disaster.
As if to cut off mounting criticism, on Saturday White House spokesman Robert Gibbs posted a blog entitled "The Response to the Oil Spill," laying out the administration's day-by-day response since the explosion, using words like "immediately" and "quickly," and emphasizing that Obama "early on" directed responding agencies to devote every resource to the incident and determining its cause.
In Pass Christian, Mississippi, 61-year-old Jimmy Rowell, a third-generation shrimp and oyster fisherman, worked on his boat at the harbor and stared out at the choppy waters.
"It's over for us. If this oil comes ashore, it's just over for us," Rowell said angrily, rubbing his forehead. "Nobody wants no oily shrimp."