Watchdog Warned Woodside's Browse Gas Plan Could Harm Rare Reef and Endangered Turtles

Woodside Energy's proposal to drill for gas off the north-west coast of Western Australia could significantly damage "exceptional" coral reefs, and it may not be possible to bring the risk of an oil spill down to an acceptable level, according to advice prepared for the state's independent environmental watchdog.

A draft letter from the WA Environmental Protection Authority, written in 2023 and seen by the Guardian, strongly criticised the company's plans for the Browse gasfield. It said Woodside's measures to protect endangered turtles and blue whales near Scott Reef would not be effective. Scientists have warned the project could harm the reef ecosystem, which supports more than 1,500 species, many found nowhere else.

EPA staff presented the draft to the authority's board in December 2023. Two months after it was discussed, in February 2024, the EPA wrote to Woodside saying its preliminary view was to reject the development. That was a major setback for a plan to drill more than 50 wells and pipe the gas 1,000km to the company's ageing North West Shelf export plant, which sits next to the world heritage-listed Murujuga rock art.

Woodside, Australia's largest fossil fuel company, won approval last year to run the North West Shelf until 2070, but it needs Browse gas to keep the plant supplied. Browse is about 300km off the Kimberley coast and is Australia's largest undeveloped gas source. Running the processing plant until 2070 could release about 88m tonnes of carbon dioxide a year once the gas is burned. The company hopes to win approval for Browse next year.

The letter said staff advised the board there was a threat of serious or irreversible harm to turtles, whales and the wider environment from oil spills, and that the precautionary principle should be invoked, meaning the EPA should assume the worst outcomes could occur. It also said that if a well leaked for 13 days, "irreversible consequences" for Scott Reef were possible.

In response, Woodside added explosive-driven shear rams to its drilling plans, which it says could seal a leaking well in seconds and limit the "longest credible duration" of a "highly unlikely" blowout to about 12 hours. Chevron, another WA gas exporter, rejected the technology for its own wells in 2024, calling it unproven and impossible to test in the field. A Woodside spokesperson said that if the rams failed, a capping stack would stop the flow within 16 days.

The draft letter also warned that Sandy Islet, which is critical to endangered green turtles and where about 1,000 turtles breed each year, could be threatened if the seabed subsided after gas extraction. It called a plan to top up the islet's sand "high-risk" and "likely to be limited" in success. Woodside said it would not drill any wells within 20km of the islet and would restrict flaring, which can confuse turtle navigation. The letter further said noise, traffic and vessel strikes would significantly affect pygmy blue whales, with Scott Reef the only known whale feeding ground on their migration route. Woodside said whale feeding there was opportunistic, but agreed the reef and islet had exceptional environmental value.

Glenn Walker, Greenpeace head of nature, said Woodside's response relied on "fanciful and unproven technology". "It would be a major backflip for both the WA EPA and the national EPA to now recommend approving this project," he said. Greenpeace nominated Scott Reef for national heritage listing last week.

Only two of the WA EPA's current nine board members were in place when it told Woodside it was set to reject Browse. One of them, chair Darren Walsh, said the assessment had been lengthy because the project was complex and the area sensitive. A final report will go to WA environment minister Matthew Swinbourn, followed by a three-week public appeal period before a decision. The national EPA said its assessment clock was paused while it awaited further technical advice.