Roads Minister John Graham said he welcomed the scrutiny the inquiry would bring to the planning,design and delivery of the project.

“The government supported the establishment of the inquiry. The opposition did not,” he said.

“Transport for NSW has worked hard to make changes,including new lanes and traffic light phasing to keep local traffic moving in the most efficient way possible post-opening. Advice to me has been the system will need six months to settle.”

Greens MP for Balmain Kobi Shetty said it was unreasonable for the government to expect residents to continue bearing the brunt of the traffic chaos,particularly after they had dealt with years of disruptions during the construction of WestConnex.

“Transport for NSW have done what they can to squeeze as much traffic as possible through a very constrained system,but it’s clear we need some more bold solutions and the political will to implement them,” she said.

Transurban,which operates WestConnex,acknowledged the congestion on surface roads near the interchange but said its opening had led to faster trips for motorists travelling between the CBD and Sydney’s west and south-west. It cited a trip from Penrith to the CBD via WestConnex taking less than an hour,a saving of almost 10 minutes since the interchange opened.

The toll road operator said in a submission to the inquiry that potential changes to WestConnex’s signage,lane configuration and line marking were under consideration to help allay congestion on surface roads.

However,it said Transport for NSW was responsible for any actions to ease congestion on adjoining or nearby surface roads.

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