A PREDICTED "200 kilometre" megacity running from Noosa to the Tweed will never happen if Sunshine Coast leaders get their way.
But Professor Peter Spearritt, who first made the startling prophecy in 2000, has suggested the mammoth urban sprawl is already taking place.
Prof Spearritt, who works at the University of Queensland's urban history department, told the Brisbane Times, development in 2015 had joined the Sunshine Coast to Brisbane, Logan and the Gold Coast.
"We've really been there for almost 10 years, primarily because we have this linear urban form from Noosa to the Tweed with a bit of a bump out to Ipswich," Professor Spearritt said.
The population of the narrow strip between Noosa and the Gold Coast - South East Queensland's "200km city" - will swell by 2.2 million to 5.5 million in 30 years.
This growth has forced the Queensland Government to issue a draft study to be released early 2016 to give early ideas of where future residential growth will have to occur, a spokesman for the Department of Infrastructure, Local Government and Planning said.
Do you believe the Coast is at risk of becoming part of mass 'mega city'?
This poll ended on 29 June 2015.
Yes, you only have to look at all the developments cropping up
No, that's crazy you can clearly see where the Coast starts and ends
Who knows, it's hard to predict
This is not a scientific poll. The results reflect only the opinions of those who chose to participate.
"The region is facing considerable growth over the next 30 years which may see its population rise from 3.3 million people to 5.5 million people - a significant challenge that will require both infill development, and new and well-located greenfield development to accommodate this growth," the spokesman said.
"The Queensland government is currently working with local governments, non-government organisations and industry to determine how and where this growth will be accommodated prior to releasing a draft plan in early 2016 when the community will be asked for their views on how SEQ should grow."
Sunshine Coast Mayor Mark Jamieson "vehemently" rejected the concept.
"We do not want to see the Sunshine Coast become a dormitory suburb of Brisbane," he said.
"With the support of our neighbours in Moreton Bay Regional Council, we're trying to convince the State Government of the importance of this natural break to both councils and to south-east Queensland as a whole.
"It is our front door.
"You know when you arrive and you know when you leave.
"If we lose it, we lose our identity as a unique region and we lose one of our most significant environmental features."
Even UDIA Sunshine Coast president Andrew Stevens doesn't see it changing.
"I was driving up from the Gold Coast this morning and all I could see from the Caboolture service station is bushland," Mr Stevens said.
"There is a substantial 20 kilometre odd inter-urban break (between the Sunshine Coast and Caboolture). I don't believe this will ever change".
Not even the proposed future developments of Caloundra South, Halls Creek and Beerwah East were likely to remove the green break.
Cr Jamieson said the inter-urban break had "a value of at least $5 billion to the regional economy" and played an important part in branding the region.
He said it also played a key role in protecting water quality in the Pumicestone Passage.
The Inter-urban Break:
- Is a 613sq km non-urban area in the northern part of Moreton Bay region and southern part of the Sunshine Coast region
- Is loosely aligned with the Pumicestone Passage catchment
- The National Heritage-listed Glasshouse Mountains and the world recognised Ramsar protected Pumicestone Passage are significant features.
- About 52.5% is made up of national parks, state forests and forest reserves.
- About 36% is owned by the State Government and is leased for forestry purposes.
- It is characterised by land uses including rural, forestry, rural-residential, townships, tourism, community uses and extractive resources.