Sydney Airport has again achieved the lowest ranking of the country's four-biggest airports with passengers concerned about kerbside congestion at both its international and domestic terminals.
In its annual report on the state of the airports, the Australian Competition and Consumer Commission warned that the country's four largest airports – Sydney, Melbourne, Brisbane and Perth – will have to invest more if they are to resolve congestion, accommodate future passenger growth and improve service levels.
"It is likely that the current infrastructure at monitored airports will be under increasing pressure in future years given evidence of aeronautical and land-side congestion at some airports," ACCC chairman Rod Sims said.
Brisbane was the only airport to improve its quality of service, while Sydney Airport's overall quality of service was again rated the lowest among the four biggest airports.
Melbourne Airport' average quality of services was also unchanged at ''satisfactory'', while passengers' ratings of Tullamarine remained ''good''. Airlines' ratings fell from ''satisfactory'' to ''poor''.
''Airlines again expressed concerns with the standard and availability of certain aircraft-related facilities, particularly aircraft parking bays,'' the ACCC said of Melbourne Airport.
''There is evidence of emerging capacity issues in terminal forecourt areas and connecting road system.''
Sydney Airport's rating for quality of service was unchanged at ''satisfactory'', which was again the lowest among the four largest airports. Passengers' ratings of Kingsford Smith was unchanged at satisfactory, while airlines' ratings were lower at ''poor''.
''Sydney Airport's low quality of service ratings and relatively low investments in the face of on-going increases in demand, suggest that needed investments have not been forthcoming,'' the ACCC said in its report.
''While options for capacity expansion may be limited by regulatory constraints, there may be scope for addressing concerns with the quality of some aircraft-related and passenger-related services.''
All four airports also reported higher car parking revenues in the 2012-13 financial year.
Sydney Airport has the highest car-parking revenue per space, as well as the highest car-parking margin per car park space, of the country's four-biggest airports.
Travellers are slugged $56 for a car park for eight hours at Sydney, $32 for three hours and $16 for an hour. In comparison, Melbourne Airport charges $56 for eight hours, $28 for three and $14 for an hour.
The ACCC said the airports' revenues and profit margins had increased due to continued growth in passengers, which had also helped boost what they earn from car parking.
''Since 2002-03 all monitored airports have reported significant real earnings growth but in the same period ratings of average quality of aeronautical services have decreased at three out of the four airports,'' it said.
The competition watchdog said airlines had expressed concerns about a lack of parking bays at Melbourne Airport, which had worsened in recent years.
''Melbourne Airport faces runway capacity constraints in the medium-term as well as challenges enhancing the effectiveness of its land-side infrastructure,'' it said.
Sydney Airport said it ‘‘continues to listen and respond to our passengers’ feedback’’, and as part of its long-term plans intended to improve ground transport.
It also emphasised that it had invested about $2.4 billion in improving its infrastructure since 2002, and planned to invest a further $1.2 billion over the next five years.
“We continue to focus on developing the airport in a way that responds to the changing needs of our passengers and airlines,” Sydney Airport chief executive Kerrie Mather said.