Rigs to reefs: How offshore oil platforms could prevent the next great ocean extinction

Published on Wednesday, 05 June 2019

Published by Stephen Peters and Dan Millison on Wednesday, 05 June 2019

Coral could hold the key to saving the world’s oceans from the looming climate crisis. Photo: Francesco Ricciardi
Coral could hold the key to saving the world’s oceans from the looming climate crisis. Photo: Francesco Ricciardi

A few miles off the coast of Mabul, Malaysia, stands an abandoned offshore oil platform. At first glance, it’s an eyesore. But look closer. It has been converted into a resort for diving enthusiasts to explore these beautiful waters. The rig can accommodate up to 60 people in air-conditioned guest rooms. There’s a conference room, even wifi.

Another feature: the potential to save humans from extinction. The rig might be a blueprint for how to save our oceans from a tide of destruction that threatens to wipe out the support systems that make human life possible.

Healthy oceans are the lifeblood of humanity—we cannot survive without them. Small marine creatures provide more than 50% of the oxygen we breathe. In other words every second breath we take. Oceans produce 15% of the protein we consume and absorb about 40% of global CO2 emissions. In fact, they have probably naturally sequestered about 30%-50% of total carbon dioxide emitted by humankind.

But ocean acidification threatens to upend the ecological balance that produces these global public goods. Acidification happens when an increase in carbon dioxide in the atmosphere leads to more CO2 being absorbed by the oceans. This produces more carbonic acid and makes the ocean more acidic, triggering a toxic domino effect. 

The more acidic the ocean becomes, the less efficient small marine creatures are at using calcium carbonate to grow their bodies. Zooplankton, algae, shellfish, and other calcifying organisms including corals, can’t adapt to this rapidly increasing acidity. We know this from geological records which show that periods of high CO2 coincide with extinctions of calcifying creatures.

  The world could lose 90% of its coral reefs by 2052.

Since the beginning of the industrial revolution, ocean acidity has increased by 30%—much faster than any known change in the past 50 million years. Measured in pH where a lower number is more acidic, pH went from 8.2 to 8.1. This might not sound like a big difference, yet when oceanic pH reaches 7.9 or lower, coral reefs and calcifying organisms will not be able to survive, setting off a cascading collapse of marine life, possibly over a few years.

Such a scenario would have terrible economic consequences. According to the World Resources Institute, coral reefs generate nearly $30 billion annually and sustain 25% of marine life and nearly 1 billion people through coastal protection, food security, and income. More than 30% of the world’s coral reefs have died over the past several decades and 90% are projected to die by 2052, due to acidification, other forms of pollution, and overfishing. There will be no exploitable wild fish stocks in Asia for commercial fishing by 2048, according to the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services,

That amounts to an existential threat to humanity. How can abandoned oil rigs help avoid this fate?

Studies have shown that artificial reefs—which is what some offshore oil rigs have become —can be reconfigured to cultivate a limestone substrate on which coral can grow. Corrosion protection systems commonly used on offshore oil and gas facilities can cause growth of limestone on metal.  This was discovered more than 40 years ago and has been used for artificial reef projects around the world. Two of the largest such reefs are in Indonesia, on the northwest coast of Bali, and at Gili Trawangan on the northwest coast of Lombok.

Researchers at the Mote Marine Laboratory in the Florida Keys, the Hawaii Institute of Marine Biology, and others have found that the natural growth rates of coral can be accelerated by a factor of up to 50 using a micro-fragmenting process. This process can be coupled with the limestone growth process to grow coral reefs faster than they are dying off.

  Turning Southeast Asia’s 1400 offshore oil rigs into a lifesaving artificial reefs

There are about 1,400 rigs in Southeast Asia, many of which are due shortly for decommissioning. Based on experience in the United States, at least 100 of these rigs could be converted. A successful rig-to-reef program in Southeast Asia will require a lot of “learning-by-doing,” with the collaboration of governments, petroleum operators (who achieve large savings in lieu of complete decommissioning), and aquaculture specialists to foster a new breed of marine entrepreneurs.

The converted oil rig off the coast of Mabul shows how to make this approach a win-win for the environment and the economy. This enterprise isn’t simply beneficial for the future of healthy oceans and possibly life as we know it. It’s also a profitable venture in terms of both ecotourism and commercial fishing.

It also shows how the global discourse about environmental degradation needs to be reframed so that environmental solutions are more commercially viable. Unlocking the capacity to innovate and create is the first step out of a zero-sum game mentality that perpetuates a quest for unsustainable profits and causes the environmental catastrophe we now call the “Climate Emergency.”

Turning oil rigs into reefs might be easily dismissed by sceptics. Instead, we need to encourage and incentivize these ideas, and celebrate the people behind them.

They embody the kind of bold vision needed to save the oceans and prevent the next great extinction event — our own.


ADB recently announced the Action Plan for Healthy Oceans and Sustainable Blue Economies, which includes the Oceans Financing Initiative. We invite you to join us in addressing this existential threat to humanity.