The expansion of the complex, planned for the site of the current Woolworths car park on Hibberson Street by the Vinta Group, will cost nearly $27 million and balloon the total area taken up to about 10,000 square metres, including a new two-storey car park for 500 cars.

A major retail chain will also open a new store in the precinct, although the developers were coy on naming the brand. Woolworths and Big W are already in the centre.

The company has high hopes of the new centre becoming a landmark - linking the properties they already own into a unified mall.

According to the company, Vinta first built the The Marketplace, comprising the Woolworths supermarket, 25 stores and 11 offices, in 1999.

Then, in late 2005, the company developed and opened a second part of The Marketplace across the road, which included the Big W, another 39 stores and six offices.

Finally in late 2008, the company said it bought the Woolworths car park, the block the developers plan to now build on.

"The development site will provide the catalyst to expand and reposition the existing centres to become the dominant town centre in the Gungahlin region,' the company's statement said.

The developers are also proposing an overpass and underpass to link their proposed and existing assets.

"This new [underground] carpark will also be connected to the Big W centre's carpark via a tunnel underneath Hibberson Street, so customers will be able to travel freely between the carparks without the need to exit and re-enter," a spokeswoman from The Vinta Group said.

City planning authorities fear, however, this may interfere with future light rail lines.

"City Planning also flagged concerns about the overpass," its submitted statement reads, saying planners advised the developer that "Capital Metro may have issues as [the proposed] underpass and overpass may impact on light rail".

According to the same document, the Gungahlin Community Council has thrown its support behind the proposal.

"The proponent met with the Gungahlin Community Council on September 24 2014 to discuss the full DA proposal. The Gungahlin Community Council supports the application," the statement reads.

The spokeswoman also spruiked the job benefits of the new enlarged centre.

"The redevelopment will benefit the region with an increased retail offer for customers as well as creating employment during construction and with the additional stores," she said.

After community consultation ends in mid-December, the company expects construction to begin in February 2015, according to the application.