From rigs to reefs: Researchers encourage authorities to rethink oil rig removal

Oil rigs have often been highly criticized for their negative impact on the environment. But now, researchers are encouraging authorities worldwide to rethink the idea of removing all obsolete oil rigs, as well as wind turbines and other offshore installations, from our waters given that marine life can benefit from the infrastructure. 

Researchers who conducted a global survey of environmental experts found that nearly 95 percent of them — 36 out of 38 — agreed that a more flexible case-by-case approach to the decommissioning of offshore installations could benefit the environment in the North Sea, located in northern Europe. That approach would allow for more installations to be left in place or moved to what researchers described as a designated reefing location.

"Internationally, it has been decided that all artificial installations in the sea must be removed when they are no longer in use," according to a news release on the findings, which were published earlier this month in Frontiers in Ecology and the Environment, a peer-reviewed scientific journal. "But now almost 30 international researchers say that this decision perhaps should be reconsidered."    

Oil rigs worldwide were built to "withstand pretty much anything — hurricanes, tsunamis. .... So they're sitting there quite firmly," said freelance journalist Lina Zeldovich, who recently wrote an article on the topic for JSTOR Daily. "They're outliving their age, they're done. Some of them need to be taken out. Some of them will have to be taken out soon."

"It is a multi-billion-dollar effort. Should we do it? So apparently, maybe not in some cases," she said on CBSN.

Fish have made oil rigs — in place for decades — home. The rigs are structured in ways that offer marine life shelter and protection, said Zeldovich. "And scientists in some cases are seeing this new diversity around these rigs, and they're saying: maybe we should leave them there or cut them in parts and leave parts of the rigs there, to keep these fish living," she said.

In the North Sea, for example, an old oil rig will have the same function as a stone reef, said Jonas Teilmann, a senior researcher from Aarhus University who was involved in the study.

"We have observed a significantly increased biodiversity around the old facilities and encourage the authorities to consider, in each individual case, whether an exemption from the demand for removal can be granted," Teilmann said. 

Zeldovich noted, however, that "there are some caveats." Scientists are discussing whether regulations regarding oil rig removal should be changed, and that could possibly have negative repercussions. 

Requirements that offshore oil and gas infrastructure be completely removed were put in place by the 1958 Geneva Convention on the Continental Shelf "to make sure that the oil companies took responsibility for their obsolete infrastructure," according to Zeldovich. 

Some people are concerned that changing the regulations could open loopholes that would let rigs stay in place even when they should be removed. "Maybe some are leaking, for example," Zeldovich said.

"It also can cause other issues," she added. "Now it sounds like drilling offshore is not really damaging the ocean, so some people can make a point of: 'let's drill more.'"

"And the last thing that some scientists are thinking about is, can it bring some invasive species? So if you have some species that are sort of floating through the water and they have nothing to settle on, they don't settle. But now if you give them some space to hang on and settle, they might."

Still, the group of international researchers is urging officials and politicians worldwide to temporarily suspend mandatory decommissioning of offshore infrastructure, according to the release on the researchers' findings. 

"According to the researchers, the competent authorities should instead make an environmental assessment of which structures to leave and conduct follow-up investigations of the effect of the new reefs," it says.