Environment

Should today's oil rigs be tomorrow's reefs?

Cod gather around a sunken oil rig
Cod gather around a sunken oil rig
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Cod gather around a sunken oil rig
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Cod gather around a sunken oil rig
An oil barrel serves as a shelter for a fish
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An oil barrel serves as a shelter for a fish
A brittle star occupies a subsea installation less than one year old
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A brittle star occupies a subsea installation less than one year old

According to an international understanding, all offshore oil rigs, wind turbines and other structures must be removed from the environment once they're no longer functional. A new study, however, claims that it might be better for marine life if such decommissioned installations just stayed put.

Typically, structures such as oil rigs remain operational for at least 20 to 30 years. During that time, an increasing number of marine plants and animals adhere to their underwater pilings, pipes and other parts, or take shelter amongst them. Larger animals are drawn in to feed upon those organisms, creating a whole ecosystem.

When the structures are dismantled and taken away, those ecosystems vanish.

A brittle star occupies a subsea installation less than one year old
A brittle star occupies a subsea installation less than one year old

With that in mind, an international group of approximately 30 scientists is now suggesting that the decision to unquestioningly remove all such structures should be reconsidered – instead, authorities could determine if it were best to leave or remove structures on a case-by-case basis. Along with continuing to provide the local marine life with a home, leaving the installations alone would also save the money that would otherwise be spent on tearing them down.

"By leaving the rig in place, we may ensure greater biodiversity in the sea," says senior researcher Jonas Teilmann, of Denmark's Aarhus University. "The physical structures also ensure that the areas will not be trawled. The heavy trawls turn the seabed into a uniform desert with poor biodiversity."

A paper on the research was recently published in the journal Frontiers in Ecology and the Environment.

Source: Aarhus University

5 comments
Synner
As a petroleum engineer working on rigs out of TX - the benefits of rigs on local marine life can’t be understated (side note: In the Gulf of Mexico a lot of the rigs are just left sitting there or are sunk into the ocean. This practice of full removal mainly applies to other areas especially the North Sea which requires full removal). We place unmanned submersibles into the water regularly for inspection, and the marine life is often so dense it makes it hard to see anything else. You see some pretty cool things down there, it’s like an island of life in the middle of a desert of nothing - move a mile away from the rig and it’s desolate & barren.
Deres
I have always wondered why the legislation does not ask to create "artificial reefs" from those structure. They could had some material where plants and corrals easily adhere and holes for fish to hide. Moreover, if some corals are put on the structure, they could become permanent.
ljaques
It is an excellent idea to leave them there, and I hope they do so in the end. Trawling should cease, as well.
Zachary Smith
"Should today's oil rigs be tomorrow's reefs?" Not entirely sure but if making it a reef is cheaper than the alternative, I'm certain they'll attempt to sell it to us in such a way as to make us believe they care about the ocean.
warren52nz
I've been saying for years that throwing an empty (glass) bottle off a boat is probably good for the marine life because: a) glass is inert, essentially made from sand and b) it would provide a safe habitat for small creatures and thus create a new ecosystem However I've had a hard time convincing the skipper of any boat I happen to be on but I'm convinced it's true.