Deepwater Horizon – Part 3 – The Aftermath

by | Nov 4, 2016

Broadly speaking, the Gulf of Mexico and nearby coastal environments were indeed harmed during the Deepwater Horizon oil release. But, despite the size and length of the release, most scientists agree that the environmental damage was not nearly as severe as it could have been.

At the peak of the response, BP, the U.S. Coast Guard, and the federal government had 45,000 people, over 6,000 vessels, and over 1,000 miles of installed booms installed to contain and clean up the released oil. All cleanup operations were under the command of the Incident Commander, a Four Star Admiral of the U.S. Coast Guard. Foreign countries offered assistance and boats from as far away as Taiwan, and Holland participated in oil skimming operations.

This is the third article in a three-part series. If you haven’t read the first two articles of the Deepwater Horizon incident, you can read the first by clicking this link: Deepwater Horizon – Part 1.

Impact and Extent

The first oil-covered bird was found on April 30th, which led to 12,000 volunteers to call the Audubon Society to assist with the rescue. Ultimately, 11,000 birds, sea turtles and mammals were rescued, cleaned and released.

Forty percent of the viable fishing and shrimping territory in the Gulf, 80,000 square miles were shut down by the Federal government by June 2010. BP attempted to ease the loss of income by hiring commercial fishing vessels to assist with the cleanup in a program called “Vessels of Opportunity”. Fishing would not fully reopen for almost two years later.

The Unified Command authorized the use of 500,000 gallons of chemical dispersants to help in the cleanup – the largest quantity of dispersants ever used for a spill. How these dispersants may have affected the environment remains controversial.

Oil from the spill reached 600 hundreds of miles of shoreline, and vast areas of the Gulf were depleted of oxygen when bacteria degraded the hydrocarbons in the water column. Biodegradation started almost immediately after the spill as bacteria degraded dissolved methane, ethane, and propane in the water column.

As bad as the spill was, it could have been much worse to fisheries and the coastal water if it were not for warm Gulf temperatures that enhanced bacterial degradation of the oil in upper waters, circular gulf currents, and a persistent north wind that kept the bulk of the oil away from the coastline. The following time lapse video shows oil migration during the spill event.


A figure from the National Commission Report to the President illustrates the maximum extent of oil.


It is generally agreed that about 4 million barrels of crude oil and associated hydrocarbons were released during the three months it took to kill the well.

Oil Capture

The National Commission estimates that cleanup efforts removed approximately 25 percent of the released oil and emulsified oil, and tar balls floating on the water and deposited on beaches; 25 percent of the oil evaporated at the sea surface and 25 percent became dispersed into the water column to be degraded by bacteria in upper waters or transported and diluted in deep waters. The remaining 25 percent was captured at the wellhead, burned on the sea surface, or skimmed with booms.

Local Industry Returning to Normal

Tourists have returned to the beaches. Some residual oil and tar balls buried sediment still work their way to the surface after storms, but for the most part, things look normal on the beaches. Some bird nesting sites and fish spawning areas contain elevated concentrations of certain hydrocarbons but, again, nesting and spawning appear to be normal.

One surprise outcome of the spill is the growth of the shrimp industry: shrimp abundance has increased in the hardest hit areas, and studies show shrimp and other seafood now have less petroleum chemicals in their system than before the spill. Scientists are not sure why, but it may have to do with the temporary loss of oxygen from the hydrocarbons, evolving bacteria which removed oil from prior spills, or that the spill killed off a shrimp predator.

Regardless of the reason, shrimp are abundant and more chemical free than before the spill, in an unanticipated consequence of it.

Lingering Effects

Like public trust, some ecosystem damage can be irreversible. Lingering public doubt and increased tar balls will be Deepwater’s legacy. Corporate culture may have changed from the spill, which could result in safer oil platforms and operations, but there is little evidence that public trust has increased.

Deepwater Horizon Aftermath Cost

In the end, it cost BP, Halliburton, and Transocean about $60 billion dollars to kill the well, compensate damaged parties, pay fines and legal fees, clean up and monitor the environment and settle legal claims. All of this is in addition to the roughly $50 billion dollars (in 2010 prices) in lost crude oil production resulting from the spill.

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