Perth Airport's annual passenger growth could quadruple to 40 million in the next 17 years - more than double the estimate by the airfield's owners - according to a State Government paper.
The WA State Aviation Strategy Issues Paper, which has just been released for comment, warns that "even that figure, which represents a growth of 7.7 per cent a year, is conservative given over the past five years passenger numbers have soared by 9.2 per cent a year".
Plane movements are also breaking records, increasing by 260 per cent since 1992 to 141,000 a year.
The report warns of the importance of investment in the airport's infrastructure to meet demand but Perth Airport Pty Ltd chief executive Brad Geatches yesterday dismissed the figures.
"The past is not a good indicator of the future and there are very good structural reasons why we expect the annual growth rate to slow materially," he said.
Perth Airport argues that much of the demand has been driven by fly-in, fly-out workers for the construction phase of big projects and demand will peak about 2015.
"The net effect is that FIFO passenger numbers are expected to flatten and, potentially, decrease for a period after construction activity peaks," Mr Geatches said.
He also believed that outbound international growth rates for WA would "slow materially over the next few years".
Construction of a new regional terminal is under way and work on extensions to the international terminal is set to start shortly. But the paper says these will not be adequate for the growth forecasts.
However, one airline executive believes that "past growth patterns are a better indicator of future trends".
"When you put the oil and gas coupled with mining sector projects together, you would have to say that the growth prognosis for the next 20 years will remain very positive," the executive said.
"Perth will eventually be bypassed by direct connections from the Pilbara to the Eastern States as the Perth experience is simply too hard."