June 15th, 2010
11:45 PM ET

How the oil-disaster flow estimates have evolved

U.S. government officials on Tuesday said they now estimate the ruptured BP well in the Gulf of Mexico is spewing 35,000 and 60,000 barrels (1.5 million gallons to 2.5 million gallons) per day; that's significantly more than the first estimate of 1,000 barrels per day in late April.

Below is a recap of the different estimates that officials have made, and when they made them, since the disaster began with the explosion of the Deepwater Horizon oil rig on April 20.

- April 23: Three days after the explosion of the Deepwater Horizon rig, and one day after the rig sank, Coast Guard Rear Adm. Mary Landry said crews were cleaning up a 1- by 12-mile-long oil slick spreading through Gulf waters. She said crude oil did not appear to be leaking out of the wellhead but that remote vehicles would survey the scene. BP officials had said a day earlier that BP they did not know whether oil or fuel was leaking from the rig. But BP Vice President David Rainey said: "It certainly has the potential to be a major spill."

- April 24: Landry said oil was leaking from two places - later to be clarified as two places on the riser pipe extending from the well's blowout preventer - at a preliminary estimate of about 1,000 barrels (42,000 gallons) a day. Officials later said that the two leaks were found within 36 hours of the April 20 explosion.

- April 28: Landry said the estimated amount of oil spilling into the Gulf of Mexico has increased to 5,000 barrels (210,000 gallons) a day, five times the initial estimate. The new estimate was based on analysis from the federal National Oceanic and Atmospheric Administration, she says. Also, BP official Doug Suttles said the company has found a third leak in the riser pipe.

- May 2: Coast Guard Commandant Adm. Thad Allen said it was impossible so far to know how much oil will eventually leak.

"We lost a total well head; it could be 100,000 barrels [4.2 million gallons] or more a day," Allen told CNN's "State of the Union." The official estimate, though, remained at 5,000 barrels (210,000 gallons) a day.

"This spill, at this point in my view, is indeterminate," Allen said. "That makes it asymmetrical, anomalous and one of the most complex things we've ever dealt with."

- May 13: After BP released underwater video footage of the leak, independent experts such as Purdue University associate professor Steve Wereley said the flow rate is probably much higher than the official estimate.

Wereley estimated that about 70,000 barrels (2.94 million gallons) of oil were leaking each day, based on an analysis of video of the spill. "You can't say with precision, but you can see there's definitely more coming out of that pipe than people thought," he said. "It's definitely not 5,000 barrels a day."

- May 27: A panel of government experts estimated the well is spewing oil at a rate of 12,000 to 19,000 barrels (504,000 to 798,000 gallons) a day, U.S. Geological Survey chief Marcia McNutt said.

- June 10: The panel of government experts, called the Flow Rate Technical Group, estimated the well was leaking 20,000 to 40,000 barrels (840,000 to 1.7 million gallons) per day through June 3. The figure was calculated in part by using high-definition video that BP released after demands from members of Congress.

The new estimate was of the well's flow rate before BP's cutting of the damaged riser pipe extending from the well's blowout preventer on June 3, McNutt said. After BP cut the riser that day, it placed a containment cap over the preventer's lower marine riser package to capture some of the leaking oil.

Scientists estimated that the spill's flow rate increased by 4 to 5 percent after the well's riser pipe was cut last week in order to place the cap atop the well.

BP said that with the cap, it was capturing about 16,000 barrels daily and sending it to a ship on the surface. Before that, BP was capturing some oil through a siphon inserted into the well riser.

- June 15: Government officials increased the estimate to between 35,000 and 60,000 barrels (1.5 million gallons to 2.5 million gallons) per day.

The change was "based on updated information and scientific assessments," the Deepwater Horizon Incident Joint Information Center said.

"The improved estimate is based on more and better data that is now available and that helps increase the scientific confidence in the accuracy of the estimate," it said.

soundoff (141 Responses)
  1. Jim Demidoff

    I watched the BP CEOs opening address on CNN today. The most interesting thing I took from it is that he said they eventually plan to have enough equipment to capture 80,000 barrels a day. If they can manage to capture that much from the containment vessel not including the leakage from around it, how much is the real leak rate. It must be at least 100,000 barrels in a best case scenario. I think that they could capture more but the containment vessels design probably only allows for around 80,000 barrels per day.


    June 17, 2010 at 5:59 pm | Report abuse |
  2. Dr. Anthony Hayward

    I try to ask BP for you next tym I see heem too find out fer you ok Ravi. It hard to no rite off becaz it be so far under the oshun. If our stoopid contracters ackshually werked on wut they wur supossed too. If I gessed I wud say it wud be only a few gallons here.

    I want to go on record tew say that I jus got dun in your United congress club meeting wher they say I stone well stuff. I did not know we had tings so far under your watur until last wendsday!! You elect meenees to your congress and I like talking with parlamehnt akross da beeg pond.

    PhredHead I am reely happy aboot Cheney not beeing in chage. He wud shewt me with a rifal which wud hert reely bad.

    You gais had yer congress man make me crys today when I try to bee nise to them this mourning. I start thinking since yu soo meen that you dont need your fishys anyways and that your pellikans shud jus stay brown like theyr name says brown pellikans anywysa!! BAIAGAIN!

    June 17, 2010 at 6:02 pm | Report abuse |
    • Abedin

      everyone is full of beans the BP oil spill on a scale of natural daristess does not make the top twenty it was much much less damaging than the pundits wanted you to believe. the worst natural disaster in american history was the great dust bowl of the 1930 s/References :

      April 24, 2012 at 2:40 am | Report abuse |
  3. Dr. Anthony Hayward

    youre congress man maak me cry today. i dun no why everwon here bee so meen to mee! it only few gallons of oil so why congress so mad and make me cry. I start to tink you no need feeshes and dat if you nam pellikan brown pellikan it shud reely bee brown!

    June 17, 2010 at 6:05 pm | Report abuse |
  4. leftyavenger

    The Republican deregulation of oil companies has led to this disaster. When Big people like BP can skip on essential materials like a shutoff valve so that their executives receive a bonus stimulus package, this is what happens. What can us Little People do, act like socialists who care about the environment? I think that the truth is finally coming out, Obama tipped his hand the other night stating that the Usa is running our of oil. Now we have the BP executives stating the obvious: they are big corporate people who run the world and we are small little people who vote and it doesn't really count.

    June 17, 2010 at 6:08 pm | Report abuse |
  5. John

    Did it ever occur to anyone that BP does not want to recover 100 percent of the oil leaking because that "is" the accurate per day leakeage # or a very good basis for it!!–(or at minimum less 5 percent of collected oil once leak is 100 percent being recovered to surface since cut and cap procedure)....I do not think they really want that # out.
    maybe best to stall ( Put in a good show) in hopes that the next capping procedure attempt work's then the real # will be unknown...Just as no one can claim if it was BP oil that killed some of these animals...I think the .001 that were not killed by BP oil are not worth squabeling over–BP should take responsibility for all the death that happens there( – last 3 years averages)–no questions asked!!

    June 17, 2010 at 6:11 pm | Report abuse |
  6. John

    what temperature is this oil coming out at? and will it heat–or cool–the Gulf in the immediate area?? anyone of you guru's know? this could be another effect on the climate and hurricane formation/strengthening.

    Also if anyone knows about the dust bowl/depression it was actually worse than this OIL BOWL/depression as of date
    especially in human lives lost and ecological loss. search youtube for (AMERICAN holocaust) about Black Monday (not Black friday)..it shows some pretty wild stuff about black GOLD let's not bury hidden historical truth. not to say this will not outgrow the dust bowl if something is not done, I think it is premature to claim history or estimate total cost's. so quickly this is far from over after all...but I sure hope it is not as costly as the Dust bowl in terms of ecological economical human etc. etc. etc. and wildlife losses

    June 17, 2010 at 6:39 pm | Report abuse |
  7. John

    besides any temperature changes this might cause–immediately due to differences in oil coming out of the ground and sea temperature differences (if any–but I am certain there must be)......I guess the water tables er should (we call them oil tables now?) will rise too!! add that into these calculations how much oil would need to leak to add an inch to sea level and if in the case of a total release of the reservoir's contents will florida me emmersed in watery oil??

    June 17, 2010 at 6:52 pm | Report abuse |
  8. John

    well in reality we are kind of fooled by phrases and deception by big wigs all the time-think about it–federal reserve–hmm is it not actually a deficit or do we have a pile of cash building up??-Homeland security-Does this imply the safety of the American people... or the land secured-(and for/by whom)??National health care-does this imply healthier people with the best care or a healthier nation through health expierementation and the selective culling of the herd?? Lies and half truths are what built this entire situation why would anyone ecpect less at this point of the game!!?--EPA quote–The air is safe this is the norm to first responders in massive incidents like this and 911!!!-
    Well we have beaten worse in the past and hope the people triumph over this bag of lies also!!

    June 17, 2010 at 7:15 pm | Report abuse |
  9. Mark

    I stand by my original estimate based on a simple mathimatical formula. It is June 28th and my estimate of gallons of oil spilled into the Gulf of Mexico is 322,195,394.2784 gallons of oil. Engineers and experts have refuted my claim by claiming there are errors in my formula. Of course my formula is not perfect but presents a logical opinion based on my methodology. In the end you might find that my estimate describes a lower bound of the flow. The use of dispersants in the hundreds of thousands to millions of gallons of corexit are designed to hide the full extent of the disaster. The use of corexit, a toxic compound is a disaster in itself. I am ashamed that our government granted any permit for BP to conduct any operations in US territorial waters. Their track record is deplorable, their safety standards are comparable to that of third world countries and the permits for them to drill should have NEVER been granted. Thank you Mr. Obama for making all of this possible. THE GULF IS GOING TO DIE!!! Only God can help us now. You wouldn't understand because you are a Muslim...

    June 28, 2010 at 5:01 am | Report abuse |
  10. Norman

    My own estimate made a few days after April 24 was 18,000 barrels a day. This clearly was different than the 1000 barrels per day being disseminated at that time. My estimate was based on our published research
    and was thought by me at the time to be a minimum estimate. It is still hard to understand why our government would underestimate the flow so badly.

    June 29, 2010 at 11:48 pm | Report abuse |
1 2 3 4 5 6