What Caused BP’s Deepwater Horizon Disaster?

The smoke has literally cleared from BP’s Deepwater Horizon disaster. Now comes the dirty work of figuring out who to blame.

Deepwater Horizon on fire


The smoke has literally cleared from BP’s Deepwater Horizon disaster. Now comes the dirty work of figuring out who to blame. According to a nearly 200-page report released this week by BP, the disaster was caused by multiple companies and “work teams” that contributed to “a complex and interlinked series of mechanical
failures, human judgments, engineering design, operational
implementation and team interfaces.”

BP’s report blames a handful of key players for the accident: Transocean (owner of the ill-fated rig), Halliburton (the company that cemented the well) and itself. The report identifies four critical factors that triggered the disaster, none of which should be too surprising to anyone who watched the oil spill unfold. BP notes that well integrity was not established, hydrocarbons entered the well undetected and well control was lost, hydrocarbons ignited on Deepwater Horizon, and the blowout preventer failed to seal the well.

Reading between the lines of the report shows that BP deflects much of the blame. BP’s report claims, for example, that the well blowout occurred at the center of the pipe and not outside of the annulus (the shoddy well casing chosen by BP). That would mean that BP’s choice of a cheap well casing didn’t play a part in the disaster.

The company does admit that it played a part in the disaster. The report notes that BP incorrectly interpreted the well’s pressure test, and that BP employees missed out on the warning signs that indicated a well was about to blow out.

But BP isn’t taking enough of the blame to satisfy Transocean, which said in a statement, “This is a self-serving report that attempts to
conceal the critical factor that set the stage for the Macondo
incident: BP’s fatally flawed well design. In both its design and
construction, BP made a series of cost-saving decisions that increased

In any case, BP’s report is more of a PR stunt than anything else. BP’s report probably won’t influence the Department of Justice’s potential civil and criminal charges against the company, and Transocean is conducting a separate investigation. Still, it’s worth a look–it isn’t easy to fill up 200 pages with excuses and deflections.


[BP Internal Investigation]

Ariel Schwartz can be reached on Twitter or by email.


About the author

Ariel Schwartz is a Senior Editor at Co.Exist. She has contributed to SF Weekly, Popular Science, Inhabitat, Greenbiz, NBC Bay Area, GOOD Magazine and more