Once again, the federal government is increasing the flow rate estimate for the Deepwater Horizon oil spill. According to the Flow Rate Technical Group, anywhere between 35,000 and 60,000 barrels (1.47 million to 2.52 million gallons) of oil per day is gushing from BP’s stricken well a mile beneath the surface of the Gulf of Mexico.
The new numbers mean that an astonishing 3 million barrels of oil have spilled into the Gulf each day since April 20, making it the region’s worst offshore oil disaster. It also means that a disaster comparable to the 1989 Exxon Valdez spill, which dumped almost 11 million gallons into Prince William Sound, Alaska, has been occurring roughly every week since the Deepwater Horizon oil rig exploded, killing 11 crew.
Just last week, the government had estimated that 20,000 to 40,000 barrels (840,000 to 1.68 million gallons) of oil was leaking from the well. That guess was based on data collected prior to BP’s cutting of a leaking riser pipe on the sea floor. Though the step was necessary to enable the deployment of an oil containment system, BP did warn that it could increase the flow rate at the well.
It appears that may have happened, though an Obama administration official told The Washington Post that the higher estimate might also be the result of better data on the flow. The improved data is the result of pressure sensors in the containment cap, which BP installed two weeks ago at the government’s behest. The sensors have given scientists a more direct measurement than they’ve had in the past.
Unfortunately, the containment system currently in place is, at the moment, only capable of capturing about 18,000 barrels of oil per day. According to the Post, BP is getting ready to deploy a second capture method that will add up to 10,000 barrels of capacity. If it works, the new system will take oil and gas through the “choke” line on the blowout preventer that was used in the “top kill” operation last month. The oil and gas will be brought up the line to a ship at the surface, where BP plans to burn it in two separate flares.
The arrival of another tanker ship in mid-July could push that daily capture rate to between 60,000 and 80,000 barrels. The spill won’t be stopped until BP finishes drilling relief wells, something that won’t happen until August at the earliest.