Motorists will still be paying tolls on the Logan Motorway in 2051 – still 35 years from now - after a set of complex, expensive ownership shuffles progressively privatised the motorway since 2011.

The 30-year-toll on the Logan Motorway was to finish in 2018, because the original 30 kilometre-long Logan Motorway began in 1988.

But changes mean the tolls will now operate for 63 years, not 30 years.

The issue emerged on Thursday when Premier Annastacia Palaszczuk was questioned by a phone-in caller to ABC radio.

"Why has the government extended the period of the toll until 2051, making the residents of Logan, Ipswich and Inala pay more for this road for another 33 years (past 2018)," Jim from Forestdale asked.

Jim wrongly accused Ms Palaszczuk of making the decision when she was former premier Anna Bligh's transport minister; an issue Ms Palaszczuk was quick to deny.

However Jim correctly identified the broad circumstances of "privatisation" leading to the extension of the toll period.

Premier Palaszczuk said the issue was more complex than he had made out.

And it is.

Here is how that happened

The Logan Motorway was originally managed by the state government-owned Queensland Motorways, which began in 1980 as the Gateway Bridge Company.

On April Fool's Day in 2011, the previous Bligh government transferred about $5 billion of Queensland Motorways' tollways – including the Logan Motorway and the Gateway Motorway  – over to the Queensland Investment Corporation (QIC), effectively the state-government's banker and now with $78 billion of assets under management.

Back on April 1, 2011 – when the transfer was listed in the Queensland Government Gazette – toll increases were promised to increase by the CPI increase each year, and the toll period was extended until 2051; ie an extra 40 years.

So if you wanted to know how much longer you would be paying tolls on the Logan Motorway – until 2051, not 2018 – you should have been reading the Government Gazette on April 1, 2011.

Four years later in April 2015 Queensland Investment Corporation sold for $7 billion its holdings in Queensland Motorways to a private consortium headed by Transurban, who now runs the Logan Motorway, among others including the Legacy Way, the Gateway Motorway and the Go Between Bridge.

And then in October 2015 the first "above CPI" tolling increase – after privatisation was in place – began, when Transurban argued successfully for "over CPI increases" to cover $450 million in improvements to the Logan Motorway.

Transurban argues the "above CPI increases" will only affect trucks.

User-pays concept grudgingly accepted

The RACQ and the Queensland Trucking Association have said they grudgingly agree the yet-to-be announced truck toll increases are worthwhile.

But, both the RACQ's Michael Roth and Queensland Trucking Association's Gary Mahon agreed most motorists simply will be shocked to learn they will be paying tolls on the Logan Motorway until 2051.

"I'm sure they will be," Mr Mahon said.

Mr Roth said the RACQ "had accepted" the arrangement because it meant a new "tolled link" from Compton Road to the Logan Motorway would be built.

What the state government says

A spokeswoman for Main Roads minister Mark Bailey said the older Logan Motorway concession for 30 years did not provide enough funds for the continual upgrades.

"The original 30-year concession periods did not provide for the scale of the subsequent upgrades and associated operations and maintenance obligations," she said.

"The Gateway Upgrade Project completed in 2011 at a cost of $2.12 billion, provided a duplicate bridge, 16 kilometres of upgraded motorway, seven kilometres of new motorway and a free-flow tolling system."

'Without tolling, these substantial upgrades to both the Gateway and Logan motorways could not have been provided until considerably further into the future.

"Alternatively, funding would have to have been diverted from other priorities or other taxes may have had to be increased or introduced to fund infrastructure provision, maintenance and operation."

What the Opposition says

"This would never have happened if Andrew Fraser and Annastacia Palaszczuk hadn't broken their promise to the people of Queensland at the 2009 election not to sell assets," a spokeman said.

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