Former planner Harry Audus, who in 2009 and 2011 did modelling around closing the Victoria Bridge to cars, says many vehicles would be end up using the nearby toll road.

Brisbane Deputy Mayor Adrian Schrinner has called on the state government to share details of the impact on the road network of the potential closure of the Victoria Bridge. Premier Annastacia Palaszczuk in July promised to provide the details to council.

Mr Audus, when in private practice, found that by 2021 the nearby Go Between Bridge's morning peak traffic flow would increase by 35 per cent and its afternoon peak would increase by 20 per cent, if the VIctoria Bridge was closed to cars.

Mr Audus in 2011 also analysed the impact of council of closing the Victoria Bridge to cars when Lord Mayor Graham Quirk proposed building a second bridge beside the Victoria Bridge for buses in December 2011.

The Go Between Bridge between Milton and South Brisbane is a toll bridge carrying 14,000 vehicles a day with the toll revenue now flowing to its new owner, Transurban and then back to ratepayers in a pro-rata payment now in place.

The state government – under legislation – has restrictions on closing some free transport links if it "channels" traffic towards toll routes.

However, in South Brisbane other untolled routes would exist if Victoria Bridge was closed.

The RACQ in February asked that the Go Between bridge toll be removed.

Mr Audus said his firm's modelling also showed there would be a "slight increase on the William Jolly Bridge" in the morning and no increase in the afternoon by 2021.

The rest of Victoria Bridge's car traffic is spread through Stanley and Vulture streets in Woolloongabba before it gets to the Victoria Bridge, Mr Audus said.

"I think, in general terms, it is a very good idea to close the Victoria Bridge," Mr Audus said.

"But I don't think you can do it on its own," he said, estimating it would cost $40 million for changes to add two new bus platforms to the Cultural Centre busway.

On July 8, Ms Palaszczuk in a letter to Cr Quirk promised detailed network impact information - gathered by Neil Scales, director-general of Transport and Main Roads - would be shared with council chief executive officer Colin Jensen.

Mr Jensen was chief engineer at the Department of Transport and Main Roads, then deputy director-general, then Queensland's co-ordinator general before he joined council in 2010.

"Mr Scales will respond to Mr Jensen about assessing these impacts, in addition to how best to facilitate access to information to develop the business case for the (Brisbane) Metro project," Ms Palaszczuk said.

However, council on Thursday said it had received no specific information from Transport and Main Roads since July.

The department on Thursday sent an inconsequential one-paragraph response to questions from Fairfax Media about impacts on the road network.

Cr Schrinner said council wanted the detailed network information from the state government identified by the Premier.

"If the state government has further considered the transport network impacts from a closure of the Victoria Bridge to general traffic that the Premier requested, we ask that they share the information with us so we can update the modelling we've already done."

Mr Audus, who worked with council, Queensland Transport, Translink and five private transport planning companies, including Maunsells, said the biggest proportion of cars now using the Victoria Bridge would by 2021 use the Go-Between Bridge.

"What the firm found was that by 2021 – if the Victoria Bridge was closed to private traffic – that would result in a 35 per cent increase in the morning peak on the Go Between Bridge," Mr Audus said.

The Go Between Bridge in 2016 carries 14,000 vehicles, the William Jolly Bridge about 40,000 vehicles, Story Bridge 109,000 vehicles and the Captain Cook Bridge 132,000 vehicles.

"In the morning peak, there would be a slight increase on the William Jolly Bridge and about 1000 vehicles would go elsewhere," Mr Audus said.

"In other words, along Stanley Street and Vulture Street through South Brisbane."

In the afternoon peak the biggest (though lower than the morning peak) percentage of the Victoria Bridge's traffic would also go to the Go Between Bridge (20 per cent), there would be no increase on the William Jolly Bridge and about 8 per cent redistributed through South Brisbane, he said.

Cr Schrinner will meet with Transport Minister Stirling Hinchliffe "in coming weeks".

He said council's information shows there is room for extra vehicles on the William Jolly Bridge.

"There is spare capacity on the William Jolly Bridge for vehicles who can also access the Captain Cook Bridge which also directly connects the CBD with South Brisbane."

Mr Audus declared he provided information for The Greens to develop their Victoria Bridge plan at the 2016 Council election.