A new report has found that Sydney airport will reach full capacity in 2025, much sooner than predicted.
In a report Sydney versus the World, Commonwealth Bank of Australia analysts Andre Fromyhr and Matt Crowe said airport management has less time than expected to address how it will handle volume growth.
The report said Sydney airport will require new infrastructure such as a new runway, terminal or second site shortly after 2025, in order to meet increased demand.
AAP reports federal and state governments have been debating the need for a second airport for Sydney for 27 years.
A number of sites for a second airport have been raised from Badgerys Creek and Wilton, on Sydney's outskirts, to as far afield as Canberra and Newcastle.
During the late 1980s - 1990s the federal government spent $A170 million acquiring land at Badgerys Creek, but a decision to proceed is yet to be made.
AAP reports that a joint federal and NSW government study in March 2012, recommended proceeding with a new airport at Badgerys Creek and lifting the limit of 80 aircraft movements per hour.
The Gillard government has rejected both recommendations, but is currently investigating Wilton, south-west of Sydney, as the site for a second airport.
Federal Minister for Infrastructure and Transport Anthony Albanese said the CBA report confirms the findings of the joint study - that Sydney needs a second airport sooner rather than later.
"The government has acted on the findings of the joint study and commissioned investigations into the suitability of Wilton as the site for Sydney's second airport," he said. "The study into Wilton will be concluded early this year."
The CBA report said that lengthy construction timetables meant politicians would have to make a decision on the airport soon.