It is easy in retrospect to say that the Deepwater Horizon accident did not have to happen. The design of the blowout preventer should arguably have anticipated that a difficult-to-control well might cause the well pipe to be propelled upwards and buckle and so present a far-from-ideal piping geometry for the so-called blind shear rams in the blowout preventer to deal with.
There evidently were warnings that the well being drilled was a difficult one to control, and there were reported irregularities in the condition and status of safety devices and warning systems on the rig. However, instead of these precursors of failure being heeded, they were ignored or accepted as business as usual. In the wake of the spill, BP, Transocean (the rig's owner-operator), and the contractor Halliburton argued among themselves about who was responsible for the accident.
The presence of the blowout preventer provided a sense of backup security, in that it presumably could be called upon to control the well should anything go drastically wrong on the rig. This proved to place unwarranted confidence in an unreliable piece of complex machinery. The relative liability of the companies involved in the drilling operation gone amok will no doubt continue for some time to be argued among managers, lawyers, and regulators, and the final outcome is likely to be a financial settlement that will not get to the heart of the matter. What appears to be clear about the technical, economic, regulatory, and environmental tragedy is that the root cause of the Deepwater Horizon oil spill was at least as much a human problem as a mechanical one.
Henry Petroski is the Aleksandar S. Vesic Professor of Civil Engineering and a professor of history at Duke University. His latest book, An Engineer's Alphabet: Gleanings from the Softer Side of a Profession, has just been published.
See Prof. Petroski's December column, Made in Japan.
See Prof. Petroski's November column, An Engineer's Alphabet of Thoughts on Design.
See Prof. Petroski's October column, Distinguishing Between Scientists & Engineers.