When a Hurricane Hits an Offshore Oil Platform

Date:

31/08/2017


For most of the year, the Gulf of Mexico is a nice place to be. It has warm waters; it doesn’t have ice or winter storms. All things considered, if you insist on attaching spindly structures to the ocean floor to drill for a highly flammable substance, the Gulf of Mexico is one of the less inhospitable places to do so.

But then there is hurricane season, when all that pent-up heat in the water threatens to turn into 100-mph winds and 12-foot storm surges. So here we are in August, with Hurricane Harvey heading toward the coast of Texas. In addition to causing serious flooding and power outages, the hurricane could deal a major blow to the country’s oil and gas operations.

Offshore drilling in the Gulf accounts for 17 percent of America’s crude oil production, and the Gulf coast has 45 percent of its refining capacity. In preparation for Harvey, ExxonMobil has announced it is reducing output at its platform in the Gulf; Royal Dutch Shell and Anadarko Petroleum have already evacuated employees from their platforms. Mobile drillships will be relocated and the drilling operations shutdown. Hurricane Harvey’s current projected path is not a direct hit on the densest area of offshore platforms and refineries, but paths are always hard to predict. It is time to wait and hope for the best.

n 2005, the one-two punch of Hurricanes Katrina and Rita destroyed 115 platformsand damaged 52 others. Offshore oil and gas production in the Gulf shut down for weeks. “The overall damage caused by Hurricanes Katrina and Rita has shown them to be the greatest natural disasters to oil and gas development in the history of the Gulf of Mexico,” a government official said some months later.

The 2005 hurricane season did force the industry to take hurricane preparations more seriously. In 2008, the American Petroleum Institute released a new set of standards for offshore platforms. The changes included how high the platforms should be to account for the cresting waves of a 100-year storm. As the Times-Picayune has reported, these heights have been a “moving target for the past century.” In the 1940s, offshore platforms were 20 to 40 feet above sea level. In the 1990s, more than 70 feet. And after Katrina and Rita, they are now at 91 feet.

The platform height is crucial, says Robert Bea, a professor emeritus in civil engineering at the University of California, Berkeley, because it is supposed to protect platforms from the most dangerous part of the storm. Offshore platforms can generally deal with wind and rainfall okay, but cresting waves will do real damage. “The pressures generated in those wave crests can exceed several thousand pounds per square inch,” says Bea. Everything below the platform has to reinforced to withstand those pressures.

Bea thinks that U.S. regulations are still too weak when it comes to protecting offshore platforms from Gulf hurricanes. Other countries like the United Kingdom, for example, use a “safety case” system. Safety cases have their origins in the nuclear industry, and they proactively lay out all of the risks of a facility along with how they will be controlled. In contrast, says Bea, U.S. regulators take a more reactive approach to risks.

The United Kingdom operates offshore platforms in the North Sea, where inclement weather is common. “They have intense weather for a very long time,” says Bea. “It’s another factor that encourages them to be more proactive in these investments to prevent large failures.” The Gulf of Mexico, on the other hand, is placid and safe for most of the year. Until a hurricane hits.