No more delays: Coalition set to firm up Badgerys Creek as the site for Sydney's second airport.

The Federal Government is expected to announce Badgerys Creek as the site for Sydney's second airport early in the new year. Photo: Brendan Esposito

The Sydney council that would host a second airport built at Badgerys Creek has reversed its opposition to the plan after consultation revealed the proposal had broad community support.

Liverpool City Council formally changed its position to one of support on Monday night when it tabled research showing a high proportion of people believed a Badgerys Creek airport would benefit the community.

The Federal Government is expected to announce Badgerys Creek as the site for Sydney's second airport early in the new year.

The 1700-hectare site in south-west Sydney was bought for an airport between 1986 and 1991.

Liverpool's Liberal mayor Ned Mannoun said 30 years of indecision surrounding the airport had hampered local business growth and economic development plans for the region.

“To date, Council's position has been to oppose any proposal to build an airport at Badgerys Creek, however Council has reassessed its position based on the widespread community support for the airport,” Cr Mannoun said.

Council conducted a telephone survey, two independent focus groups and an online survey after resolving to consult the community in September.

The phone poll of 1237 people found that 54 per cent of residents supported Badgerys Creek as the location of a new airport, 35 per cent were opposed and 11 per cent indifferent.

A total of 39 people were involved in the focus groups.

The first group reversed its 59 per cent opposition to the airport to 53 per cent support by the end of the meeting "highlighting how attitudes can change once participants are provided with new information", the report to council said.

A second evening focus group, catering to full-time workers, increased its 60 per cent support to 73 per cent by the end of the meeting.

But the same trend was not reflected in the online survey, which returned 472 responses.

It found 54.4 per cent of those were opposed to a Badgerys Creek airport, compared to 42.6 per cent in favour.

This included a "disproportionally high" frequency of responses in opposition from Bringelly and Greendale, suburbs neighbouring Badgerys Creek, the council report said.

The council report said aircraft noise was the "issue of most concern" for residents who opposed the airport.

No Aircraft Noise spokesman Allan Rees said the "critical" question was whether those involved in the consultation were being asked if they supported a 24-hour airport.

"We think these things have to be pretty clear up front, because we think Wilton is much more likely to be suitable for a 24-hour airport," Mr Rees said.

Monday's meeting resolved to set up a "multi-government taskforce" to ensure council had an active role, should the Badgerys Creek site be confirmed.

The council's new position was welcomed as an "early Christmas present" by the Western Sydney Airport Alliance.

Its spokesman David Borger said an airport at Badgerys Creek "is a big tick for thousands of new local jobs and millions of dollars in investment for Liverpool".

"The process undertaken by Liverpool City Council is a great example to other councils in the region who continue to stand by their antiquated motions of opposition to the airport," Mr Borger said.