The local, state and federal governments have investigated the viability of building a second major airport in Sydney since the 1940s.[59] Between 1987 and 2000, domestic travelers through Sydney more than doubled to nearly 27 million, and international passengers served increased from 8 million to 15 million. The Sydney region passenger demand is forecast to reach 87 million passengers by 2035, more than doubling, and to double again by 2060.[60] Close to half of all scheduled flights in Australia take off or land at Kingsford Smith. In 1998 the airport handled 45 per cent of international passengers in Australia.[61]
The Federal Government has bought most of the required land in a proposed site at Badgerys Creek, west of Sydney. This site would be accessible by the Westlink M7 motorway. Despite acquiring almost all the land necessary for the building of the Badgerys Creek airport, and multiple studies and reports commissioned that recommended building the airport, in 1995 new airport leasing legislation was blocked in the Australian Senate, and construction was delayed until after the 2000 Sydney Olympics. All the major Australian airlines, including Qantas, indicated they would prefer additional development of Kingsford-Smith Airport. In 1998 most local authorities reversed their previous support of the new airport and protested against potential noise and pollution impacts. After the 2001 terrorist attacks decimated the air travel industry, the national government announced its belief that the current Sydney airport could accommodate additional air travel demands for at least another decade.[citation needed