The infrastructure project will also include improvements to ramps for drivers entering and exiting the highway.
Deputy Prime Minister and Minister for Infrastructure and Regional Development Warren Truss said the project aims to fulfil the government's commitment "to remove congestion and improve efficiency on our roads", according to a recent statement.
"The Gateway Motorway is a major arterial road for Brisbane and this stage of the $140 million project will help get traffic moving on what is often a badly congested road," Truss said.
"Not only will the widening of Mt Gravatt–Capalaba Road mean motorists get to their destinations more quickly, they will get there safely.
"We've just completed the extension of the Gateway Motorway South on-ramp to the Pacific Highway, and this widening continues our commitment to increase efficiencies for road users."
Federal Member for Bonner Ross Vasta said he was "delighted" the government was focussed on improving Brisbane roads.
"This is a much needed upgrade for Brisbane motorists," Vasta said.
"Along with the $1 billion Gateway Motorway North upgrade, it is fair to say the Australian government has a clear focus on this important corridor."
Assistant Minister for Public Transport Steve Minnikin said the project will provide a safer and more efficient connection, to and from the Gateway Motorway benefiting more than 35,000 motorists who travel on this stretch every day.
"In partnership with the Australian government, this is another example of the Newman government delivering on its election promise to deliver better infrastructure and better planning for Queenslanders," Minnikin said.
"I am looking forward to the completion of the project so we can keep Brisbane moving."
The federal and Queensland governments are jointly funding the projects, investing $70 million each into the upgrades.
