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31 million barrels of oil later, new life for old rig

31 million barrels of oil later, new life for old rig

Royal Dutch Shell’s 36-year-old Cougar oil and gas platform. The bulk of the platform was converted into an artificial reef in November.

This location, however, will never produce oil. Instead, the 3,000-ton frame, from a retired platform operated by Royal Dutch Shell, will become home to barnacles, mussels, sponges and other aquatic invertebrates and a way station for migratory fish from red snapper to whale sharks seeking food and shelter.

“These platforms are essentially the gas stations or rest stops in the Gulf,” said Ruth Perry, a marine scientist and regulatory affairs specialist at Royal Dutch Shell. “The artificial reefs allow ecosystems to grow. We’ve seen growth within hours or days or weeks.”

This new life for an old platform, called Cougar, comes courtesy of a federal program that has recycled more than 450 offshore oil and gas rigs into artificial reefs in U.S. waters. Scientists discovered long ago that as offshore oil production ventured deeper into the ocean waters off Louisiana and Texas, the platforms became magnets for shrimp, snapper, coral and other species that had long clung to scattered hard banks rising from the Gulf’s vast floor of mud, clay and silt.

The federal program, created by Congress in 1984, aimed to build on this phenomenon by encouraging oil and gas companies to leave their platform frames in deep water, where they would be transformed into artificial reefs. The program has not only created thriving, aquatic ecosystems, but also saved oil companies the expense of hauling platforms back to land, then dismantling and disposing of them.

The program, called Rigs to Reefs, also provided a public relations boost for an industry often reviled for spills and other environmental damage.

“I think basically everyone around the Gulf Coast sees it as a very positive step,” said Chris Ross, a finance professor at the University of Houston. “It’s a great habitat for marine life, and it’s much cheaper than trying to recycle it.”

Besides, he added, “What else are you going to do with it?”

Making it happen

Oil companies, required by federal regulators to remove offshore platforms from the ocean at the end of their productive life, can opt instead to work with Gulf Coast state agencies to identify which platforms would be suitable to become artificial reefs. The agencies seek permits to do so from the Army Corps of Engineers and Coast Guard, and they assume any liability for environmental damage caused by the reef. Myriad factors go into choosing a spot to deploy a reef. The state agencies avoid putting them too close to natural reefs or too far from the original site, which would drive up transportation costs.

The agencies also avoid shallow waters, shipping lanes and anywhere a ship might strike them. The ideal spot for an artificial reef is close enough to shore to allow fishermen to reach them, in an area where the sediment of the seafloor is strong enough to support a massive structure.

In 1981, Shell deployed Cougar in 337 feet of water, extracting oil and gas from what were the furthest reaches of the oil industry’s territory in the Gulf at the time. The platform, one of Shell’s first ventures into deeper waters, came with one of the first on-site computer systems to monitor wells that would produce a combined 31 million barrels of oil equivalent over their life spans.

Now, a variety of species, Perry said, will be drawn to different sections of Cougar’s steel frame, already encrusted with aquatic species like barnacles, bryozoan, sponges, oysters, mussels and coral.

The frame, some 35 stories tall, will sit on its side on the ocean floor, its steel pipes capturing different levels of sunlight that plankton and phytoplankton – a source of food for fish – need to survive and thrive. Larger fish species, including sharks, will dwell closer to the surface of the ocean than smaller ones.

The Coastal Marine Institute, a research center at Louisiana State University, has found that one of these structures, which stand on eight legs, can create habitat for up to 14,000 fish. Each platform leg can have two to 6 inches of encrustation of aquatic invertebrates on the metal, said Larry McKinney, executive director of the Harte Research Institute for Gulf of Mexico Studies at Texas A&M University-Corpus Christi.

‘It’s ocean dumping’

Some environmental groups have argued artificial reefs only pull fish and aquatic species away from natural reefs, and essentially turn the ocean into a scrap yard. And whatever environmental benefits oil platforms may offer as artificial reefs, their presence also risks the possibility of major oil spills that could devastate the fishing industry.

The 2010 Deepwater Horizon disaster cost the Gulf of Mexico fishing industry up to $1.6 billion in 2010, according to the U.S. Bureau of Ocean Energy Management, which oversees offshore development.

“It’s ocean dumping,” said Linda Krop, chief counsel of the Environmental Defense Center in California. “You have birds on telephone wire. Is that the best habitat for them, or is a tree a better habitat for them? The same thing with the ocean. What’s the best habitat for fish?”

More fish in the sea

But teams of scientists have found that these iron islands – both artificial reefs and active oil platforms – relieve the stress on natural reefs by attracting fish with new and bountiful sources of food and space for reproduction. The result is larger fish populations, which is why fishermen cluster their boats around oil and gas platforms in the Gulf, McKinney said.

Over the past decade, the size of the Gulf commercial catch has increased 28 percent, to more than 1.7 billion pounds in 2016 from nearly 1.4 billion pounds in 2006. The value of the catch jumped about 30 percent, to more than $900 million from less than $700 million during that period, according to federal statistics.

The National Oceanic and Atmospheric Administration estimates that in 2015 commercial and recreational saltwater fishing in the Gulf of Mexico generated nearly $34 billion in sales as products moved from the docks to consumers through wholesalers, retailers and restaurants, and supported about 250,000 jobs.

Snapper catches are up

The Harte Research Institute said this month it will lead a $12 million effort by 21 fishery scientists to estimate the number of red snapper living in the Gulf today. Commercial landings of the species have climbed nearly 40 percent since 2006, to about 6.5 million pounds in 2016, according to NOAA.

“Today, there are more snapper in the Gulf than 10 years ago, and many of those, perhaps even more than we know, are on artificial reefs and platforms,” McKinney said.

Commercial landings of red snapper have climbed nearly 40 percent since 2006, to about 6.5 million pounds in 2016, according to NOAA.

The Harte Research Institute has received funding from the oil industry for certain publications, McKinney, but not for any research on artificial reefs, which is funded by the Texas Parks & Wildlife Commission, which benefits from improving fish stocks. In Texas, revenue for licenses sold for saltwater fishing rose 47 percent between 2005 and 2016 to nearly $600,000, according to the commission.

Saving money

The major oil companies operating in the Gulf of Mexico – Exxon Mobil Corp., Chevron Corp., Shell Oil Co., BP and others – have participated in the Rigs to Reef program for years. Nearly half of the oil companies in the region, mostly smaller, private ones, are interested in the reef program to the extent it saves them money on transporting the platform onto land and dismantling it, McKinney said.

For Shell, towing Cougar 50 miles to the reef site rather than hauling it 100 miles to shore for dismantling and disposal saved the company $1.24 million, said Ernest Hui, Shell’s decommissioning business improvement lead. Shell donated about half the savings to the Louisiana Department of Wildlife and Fisheries “to monitor and support” the habitat, the company said.

“The economics made sense,” Hui said. “We see reefing as a benefit. We’ve been trying to do this around the world.”


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