Qld rail project delayed over safety fears

A billion-dollar Queensland rail project has been delayed indefinitely because of a potentially fatal signalling flaw.

An independent audit investigation will now determine who's at fault over the defective signalling system for the Moreton Bay Rail Link project, which was supposed to open in mid-2016.

Transport Minister Stirling Hinchliffe says he ordered the probe immediately after receiving advice about the problem on Monday morning.

Mr Hinchliffe says the current signalling system would fail after three trains passed through busy Petrie station.

The system should be able to handle 26 signalling changes at once at Petrie, but was failing after 15, increasing the risk of "signals passed at danger", he said.

"This is like running a red light," Mr Hinchliffe said.

"The operation of these signals is critical to safety and I never want to see a rail accident caused because we allowed a signalling system that didn't pass muster to operate."

When asked whether the flaw could have been fatal, Mr Hinchliffe replied: "I had very grave concerns about the reliability and the safety of the network. That's why I've made the decisions I've made today."

Mr Hinchliffe warned the signalling system would likely have caused delays spread across the southeast Queensland rail network.

He could not say how much the system cost to install nor the cost to remove and replace it.

The person to lead the audit will be announced in coming days.

Redcliffe MP Yvette D'Ath questioned whether funding cuts under the previous Newman government forced contractors to find savings and choose a cheaper, unsafe signalling system.

But shadow treasurer Scott Emerson, transport minister at the time, argued savings were found when Theiss was awarded the contract, which was determined by an independent panel within his department.

Mr Emerson said the Labor government had been in charge of the project for 18 months and should have been checking on its progress throughout.

"We're seeing Labor trying to sheet home blame to everyone else, when the reality is that they have been asleep at the wheel once again on another major project," he said.

The project, when completed, will deliver a 12.6km dual-track passenger rail line in the Moreton Bay region, north of Brisbane.

The $988 project is jointly-funded by the Commonwealth ($583 million), Queensland government ($300 million) and local council ($105 million).