Attorney general’s department advised Coalition Toondah Harbour development could breach wetlands convention

The Coalition government decided a controversial apartment complex and marina proposed for Queensland’s Moreton Bay should proceed to the next stage of the assessment process, despite legal advice from the federal attorney general’s department warning it was unacceptable because of the risk it posed to internationally listed wetlands.

The government was advised that a development inside the Ramsar site could put Australia in breach of its international obligations before Josh Frydenberg, who was environment minister at the time, recommended his department proceed with an assessment of the Walker Corporation’s long-proposed Toondah Harbour.

Under the proposal, more than 3,000 apartments would be built on top of about 42 hectares of protected wetlands. It is currently being assessed by the federal environment department, with an environmental impact statement expected to go on public display soon.

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In 2018, the ABC reported Frydenberg had rejected environment department advice that the development should not proceed to the assessment stage because it would affect the ecological character of the site, which is listed under the Ramsar convention on wetlands.

Leaked documents showed Walker Corporation was considering legal action at the time if the government ruled the development was deemed ineligible for assessment as “clearly unacceptable”.

A letter from Walker Corporation’s legal advisor to the federal government in February 2017 seen by Guardian Australia suggests the environment department based its view on legal advice from the office of international law in the attorney general’s department.

The letter says environment officials, supported by the legal advice, had told the company several times that the proposal should not proceed to assessment because developing inside the wetlands would be unacceptable under national environmental laws due to the risk of putting Australia in breach of international obligations under the Ramsar convention.

The company disagreed. In the letter to the department and minister’s office, it argued Frydenberg would not be contravening the act if he decided the development should be assessed, and not rejected outright.

Frydenberg ultimately referred a modified proposal for assessment under the Environment Protection and Biodiversity Conservation (EPBC) Act. In a letter to the Queensland government, he suggested that the boundary of the wetland could be changed, a step that would effectively delist part of the protected area to accommodate the development.

At present there is no proposal to change the boundary and the decision on whether or not to approve Walker Corporation’s most recent application – the third iteration of the project – will rest with the current environment minister, Sussan Ley.

The Australian Conservation Foundation said the legal advice referred to in the 2017 letter likely remained relevant to Ley’s assessment given the current proposal would still affect the Ramsar wetland.

“How can the government still be considering this project against the clear advice of its own international law experts?” the foundation’s biodiversity policy advisor, Brendan Sydes, said.

Sydes said it was inconceivable that Walker Corporation could demonstrate the project would not irrevocably damage the internationally important wetland, which is home to 124 rare and threatened species, including dugongs, turtles and birds.

“The Australian government should never place the interests of Walker Corporation above the protection of a globally important place. Minister Ley must take her responsibilities under the EPBC Act seriously and reject this proposal,” he said.

More recent documents obtained by Guardian Australia under freedom of information laws show the environment department reminded the government of its obligations under the Ramsar Convention.

Much of this advice is focused on consideration of whether the development would be considered “wise use” of the Moreton Bay Ramsar site.

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A draft letter from Ley to the former Queensland environment minister, Leeanne Enoch, says: “In deciding whether or not to approve the proposal under the EPBC Act, and what conditions to attach to such an approval if granted, I must not act inconsistently with Australia’s obligations under the Ramsar convention.”

In the unsigned letter, Ley said she would need to deliver a comprehensive assessment that ensured Australia met its obligations.

In another document, officials wrote a briefing for Ley ahead of a tour of the Toondah harbour site with Walker Corporation in January 2020.

The briefing says the department wanted to be involved in talks with Walker Corporation about its environmental impact statement (EIS), “particularly those that demonstrate how a net benefit will be achieved for the Moreton Bay Ramsar site”.

It notes that no Australian government had ever approved a commercial residential development of the scale proposed inside a Ramsar wetland and that, if approved, the development would remove a substantial amount of foraging habitat for the critically endangered eastern curlew.

It would also affect two known roosting sites, including one where 180 individual eastern curlews had been recorded.

The briefing says that ordinarily wise use of a wetland would relate to “traditional or cultural use of a wetland by Indigenous peoples, or to developments supporting education or public awareness of wetland values”.

A spokesman for Ley said the minister would observe all of her obligations before reaching a decision.

“These include the need to carefully consider all relevant information on the proposal including public comments, the EIS and policy and statutory documents, consistent with the requirements of the Act before reaching a decision,” he said.

Walker Corporation declined to comment and the attorney general’s department said it did not comment on legal advice it provided to government.

The environment department said it would not comment on legal advice it had received.

A spokesperson said the department was in the process of reviewing Walker Corporation’s draft EIS.

In response to questions, a spokesman for Frydenberg said: “No environmental approval was provided for the project while the former minister was in the portfolio.”