Questions about the integrity of steelwork in Adelaide's elevated South Road Superway will be considered by a committee of the South Australian Parliament, but the Transport Department has assured motorists the structure is 100 per cent safe.

Key points: Public works committee will question Transport Department

Public works committee will question Transport Department MP Tim Whetstone worries steelwork compromised

MP Tim Whetstone worries steelwork compromised Transport Department confident Superway 100pc safe

The road in the northern suburbs opened last year but Opposition frontbencher Tim Whetstone told 891 ABC Adelaide he had written to the public works committee and it had agreed to investigate his concerns.

"My background is that I am a qualified toolmaker so I've done extensive work in heat treatment of steel," he said.

Mr Whetstone said workers on the project had taken photographs of construction practices because they had concerns.

"[They said] some of that structural cord, some of the ties that are used as the strengthening rods within the concrete structures, had been compromised," he said.

"There had been oxy sets used to form the steelwork and the integrity of that steel has been compromised.

"What that does is it takes the structural integrity out of that steel cord."

Mr Whetstone said the parliamentary committee had agreed to seek information from the Transport Department and call witnesses to a hearing in February.

"There are a number of questions that need to be answered — whether there was a shortage of that structural cord, obviously it's been reported [previously] that there was a lack of skilled workforce at some stages through the course of the project," he said.

Superway 'opened early' at election time

The Opposition MP also questioned the political background to the project.

Tim Whetstone says his background as a toolmaker prompted his concerns. ( ABC News )

"This Superway was opened early — in the 2014 election — and straight after the election it was partially closed again to finish off the work ... I think it might have been rushed," he said.

A statement from the Transport Department said: "The South Road Superway has been built to the highest construction standards. It is structurally sound — 100 per cent safe for people to drive on.

"As with all major infrastructure builds, procedures were followed to ensure the structural integrity of the Superway.

"Any modification to the reinforcement was approved by the designer, with major changes reviewed by the proof engineer and the department's independent reviewer.

"Every stage of the construction was subjected to an independent review and found to be completely safe."

Mr Whetstone said he was yet to be convinced, even though he was confident that the construction company involved "have a very high reputation of road building".

"But I think the process needs to be questioned and that's simply why I've put the letter to the committee."