Queensland Deputy Premier Jeff Seeney used his ministerial powers to rezone a privately-owned caravan park on the Sunshine Coast against the wishes of the local council and the advice of his own department.

Experts said the eleventh-hour move was highly unusual and compared it to controversial interventions in local planning decisions by ministers in the Bjelke-Petersen government of the early 1980s.

A senior source at Sunshine Coast Regional Council told the ABC the move had "added several million dollars to the value of the land at the stroke of a pen".

"I've never seen anything like [this] in all my time at Council," the source said.

"This is private land, in private ownership. You wouldn't expect the state to get involved."

Mr Seeney, local LNP state MP Steve Dickson and the park's owner have all defended the move, saying it was in the interests of its 240 vulnerable elderly residents.

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"[The Council's plan] would have put 243 vulnerable residents out on the street and I wasn't going to have that," Mr Dickson said.

Mr Dickson said he was prepared to justify his lobbying of Mr Seeney to Parliament if necessary.

But planning experts have questioned the need for such ministerial "micromanagement" and criticised a lack of transparency in the process.

Rezoning will allow houses and apartments worth millions

The ABC contacted more than a dozen residents at the park and none knew anything of the Council's rezoning proposal or the Deputy Premier's intervention.

Using Right To Information laws, the ABC obtained documents showing Mr Seeney, as planning minister, in March ordered Sunshine Coast Regional Council to put the Maroochy River Caravan Park in its "medium density residential" zone, allowing its redevelopment as houses and apartments worth millions of dollars.

The council had wanted to preserve the park's existing mix of mobile caravans and small permanent units for the over-50s.

It had proposed "back-zoning" the park, in an area previously designated "mixed housing", by classifying it instead as a tourist park in the "community facilities" zone.

The owner, SEQ Properties, lobbied against this, saying it would reduce the park's value and put the company under financial pressure.

It also claimed it might have no choice but to launch immediately a development application to make use of so-called "use it or lose it" provisions, which extend existing zoning provisions for 12 months.

SEQ Properties made two submissions to Council, both of which were rejected, and lobbied Mr Dickson and Mr Seeney's office to intervene.

Emails also describe a meeting between the park owners and Mr Seeney in November 2013 at which the Council's rezoning proposal was discussed.

In early March, Matt Adams, senior policy adviser to Mr Seeney, wrote to SEQ Properties saying the Deputy Premier would not be ordering the changes requested to the proposed Sunshine Coast Regional Plan.

"The determination of specific zones in a local government area is the responsibility of council and... the state's involvement is limited to matters of state interest," Mr Adams wrote.

"This is consistent with the Queensland Government's commitment to empower local governments to have more control on the future direction of their communities.

"Given the above, the Deputy Premier will not be imposing a conditional approval requiring a change as requested in your submission."

Caravan park owner was 'broad supporter' of LNP

Mr Dickson and his staff then met the manager of planning, Garth Nolan, in Mr Seeney's office.

In a file note, Mr Nolan recorded: "I was unable to provide any specific issues... that could be considered as a state interest to justify such a change".

But 10 days later Mr Seeney reversed this position.

Just a day before Sunshine Coast Regional was due to vote on its regional plan, Mr Seeney wrote to Mayor Mark Jamieson making the State Government's endorsement of the plan conditional on including the caravan park in the medium density residential zone.

No reasons were given.

SEQ Properties is a "broad supporter" of the LNP, according to the company's chief executive. ( ABC News )

Mr Seeney told the ABC it was "appropriate for the State Government to intervene when Council planning decisions remove a landholder's existing property rights".

He said the Council's planned rezoning "would have resulted in the potential loss of much-needed affordable housing for 240 Sunshine Coast residents".

Mr Seeney said his department, by refusing to act, had got it wrong.

"After receiving the representations from Minister Dickson... and after reading the submissions that had been made, I reached the view that the department's decision was incorrect and I gave the direction to correct it."

SEQ Properties chief executive Angus Booker said the company was a "broad supporter" of the ruling LNP and had attended two fundraising lunches for the party.

Emails describe a meeting between SEQ Properties director David Johnston and Mr Seeney in November 2013 at which the Council's rezoning was discussed.

Mr Seeney said he did not recall meeting Mr Johnston and had "no knowledge of whether he'd made a contribution to anybody".

Planning intervention 'reminiscent of Bjelke-Petersen'

Planning experts said Mr Seeney's intervention was highly unusual, lacked transparency and sent a chilling message to local councils.

"There clearly should be better grounds for intervention on behalf of a state interest than what we've seen in this case," said Dr Laurel Johnson, lecturer in planning at the University of Queensland.

Dr Johnson said the decision could undermine good governance by local councils and their confidence when making planning decisions.

Planning decisions often affected the value of properties and this wasn't grounds to justify ministerial intervention, she said.

"Land use planning doesn't guarantee us a particular property value," she said.

"This reminds me of the days of ministerial rezoning in the 1980s under the conservative government of that time."

Dr Chris McGrath, a barrister and senior lecturer in planning law at UQ, said: "To me, the real question is why the Deputy Premier needed to be involved in this micromanagement of the planning scheme process. There does not appear to be any state interest involved."

"The process that was followed and the Deputy Premier's last-minute decision seems very strange and lacks transparency."

Caravan park resident Stan Lonsdale said many of the residents were very old and would find it difficult to find accommodation if forced to move out.

He said there had been no information from the park's owner about the future of the site.

"We're sort of second-class citizens, I think, really," he said.

Premier Campbell Newman criticised Sunshine Coast Regional Council earlier this year for not doing enough to encourage development in the region.

He said property developers had told him they had found it difficult dealing with the council.