Tom Koutsantonis wants inquiry to include contractor Laing O’Rourke over Darlington project wall collapse

The Opposition wants an inquiry into the collapse of a concrete retaining wall in the Darlington upgrade to rule out the financial troubles of the major contractor as a cause.

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The Opposition has called for an inquiry into the collapse of a concrete retaining wall at a section of the Darlington upgrade project to rule out the financial troubles of the major contractor as a cause.

Traffic restrictions will in be place for six weeks along one of Adelaide’s busiest thoroughfares after rain caused a non-structural concrete retaining wall to collapse on Monday.

Investigations launched by the State Government began with the cause already deemed likely to be water leaking between a concrete retaining layer sprayed onto a dirt embankment, and the soil itself.

The Opposition wants an inquiry into the collapsed concrete barrier at the Darlington upgrade project. Picture: 7 News

But Opposition transport spokesman Tom Koutsantonis — asked to leave the site by workers during a media conference on Tuesday — said contractor Laing O’Rourke should be part of any investigation.

The Queensland Building and Construction Commission suspended the UK-based company’s licence for a week in March while it provided evidence of its viability.

The company was not available to respond on Tuesday, but Mr Koutsantonis said: “I don’t know if an independent audit will uncover if any corners were cut. If corners were cut, the taxpayers deserve better on a $620m contract’’.

Opposition transport spokesman Tom Koutsantonis was asked to leave the site by workers during a media conference on Tuesday.

Laing O’Rourke was appointed by the previous Labor state government and Liberal federal government as one of the major contractors for the 3.3km and $620m Darlington Upgrade Project.

A department spokesman said the department and construction company Gateway South were investigating the damage, between Sturt Rd and Flinders Drive.

“The impacts of rain events has been taken into consideration as part of the design and construction,” he said.

“However, in this unusual circumstance, water has penetrated behind shotcrete wall in the section between Sturt Road and Flinders Drive.

“Remediation works are required to prevent further ingress and repair the damaged shotcrete.”

The spokesman said testing was continuing to “determine the full extent of damage ahead of required remediation works”.

“Works in other sections of the project are able to be undertaken while remediation works are ongoing,” he said.

Transport Minister Stephan Knoll said: “South Australians can have full confidence that this project will be operational as scheduled by the end of the year.”