Transport Minister Troy Buswell believes motorists will adapt quickly to the diversion of Riverside Drive, which takes effect today.
The section of Riverside Drive between Barrack and William streets is now closed and traffic will be diverted via those streets and The Esplanade to make way for Elizabeth Quay.
"People have already been adjusting their travel patterns," Mr Buswell said. "I've noticed the usual band of naysayers out there saying we're all doomed and the world has ended because Riverside Drive has been diverted.
"They're exactly the same people who said that when we put the third lane into the Graham Farmer Freeway tunnel.
"I reckon in a few months people will look back and go: 'What was all that (fuss) about?' Diverting Riverside Drive will have an impact.
"People will get used to it."
Shadow transport minister Ken Travers said the removal of part of Riverside Drive was designed to force traffic on to other roads "as far south as Manning Road and as far north as Walcott Street".
"That is going to add to congestion in Perth," he said. "What we needed was a major investment in public transport to match that closure."
Yesterday, a free smartphone app was launched that will allow motorists to spot roadworks, accidents and traffic snarls in real time. The Right Move Perth app helps motorists and public transport users plan their journey by providing live information on traffic conditions and disruptions from Main Roads, the Public Transport Authority, the City of Perth, the Weather Bureau and Google.
"Clearly, people are hungry for accurate, real-time information to help them make good decisions when it comes to transport. This will do it," Mr Buswell said.
The app cost the Department of Transport $220,000.