It’s not hard to see why some are reluctant. The extraction and burning of fossil fuels including oil and gas are major drivers of climate change. Overall, in 2019, gas made up 21% and oil 34% of the world’s CO2 emissions from fuel, with a significant proportion coming from offshore rigs like these and thousands of others.

But the objections are not just symbolic. There are concerns that the cost savings offered to oil companies under the rigs-to-reefs programme could encourage them to expand, Hislop notes. She adds that research and discussions about what to do with the rigs once they have been decommissioned are ongoing.

But Blue Latitudes says the aim of rigs to reefs is not to reward polluters and boost the oil industry, but to protect valuable marine habitats by offering an alternative to complete platform removal.

If California’s platforms are toppled, it would result in the loss of 27 huge marine ecosystems. Some of these rigs are taller than the Eiffel Tower – the Harmony platform in the Santa Barbara Channel, for example, reaches depths of 1198ft (365m). “California platforms are some of the largest and deepest in the world,” says Hazelwood. “You don’t even see the beams, they are so encrusted with marine wildlife.”

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