The Victorian Civil and Administrative Tribunal has given the green light for the 30,000-square-metre expansion, which will make it the biggest development in Highpoint's 34-year history. The expansion increases the centre's size by an estimated 25per cent.

An extra 1000 car spaces and 100 new shops will be housed under the expansion. Project developer GPT Group praised the VCAT ruling as a win-win.

"It's a pretty easy decision for VCAT when both parties are happy," GPT development manager Damien O'Connor said.

"We've been involved in 12 months of community engagement and the residents had a number of items that they put forward, and we subsequently met with the community groups and reached a list of outcomes."

Mr O'Connor cited changes made to plans for the Warrs Road landscape as an example of concessions made on behalf of the developer.

"The new plans allow for a buffer zone between the ring road and we believe this will deliver a better landscaped outcome."

But Maribyrnong Resident's Association secretary Alan Ross said that even though some small changes were made in the interests of residents, the main concerns about increases to traffic volume remained.

"We're not entirely happy with the result," he said

"We are still really worried that the existing traffic situation was deemed as adequate in the traffic surveys in the first place.

"Neither the council nor VicRoads offered any further advice except that everything would just be hunky-dory. I guess time alone will prove who's right," Mr Ross said.

Cr Catherine Cumming was the sole dissenting voice when the original plans were proposed to the council in February.

"The traffic report was done by those with a vested interest in Highpoint and, surprise, surprise, the report came back suggesting the increase will have minimal impact," Cr Cumming said. "You'd really have to have your head in the sand if you didn't think that this development will have an impact."