Last week, Plenty residents who face having their homes demolished to make way for the expanded road told an independent panel hearing the project should be scaled down.

Forty residents raised $18,000 for the three-day panel hearing earlier this month.

VicRoads is seeking to acquire land to turn the two-lane road into a four-lane road, with service lanes, bus lanes and on-road bike lanes.

The speed limit would increase from its current 70 km/h to 80 km/h.

Planning consultant Michael Dunn said: "Everyone knows the road desperately needs an upgrade. The question is how big the road should be."

Mr Dunn said the acquisition was a "land grab", where VicRoads was acquiring more land than needed to build the road so they would have flexibility in planning the final route.

Much of the land VicRoads wants to acquire would be to make way for service lanes, he said. Under the proposal, Plenty Metropolitan Fire Brigade would be forced to drive nearly 500 metres in the opposite direction along a service lane to travel south.

Plenty resident Des McQueen – whose older house and sawdust factory are both in jeopardy – said residents were hopeful speed limits would be reduced and service lanes abolished to save more homes.

Traffic engineer Stephen Pelosi – on behalf of residents – argued projected traffic could be accommodated in the existing single lane road. Mr Pelosi also said the duplication would only improve peak hour traffic on Yan Yean Road until the traffic hit the congested Diamond Creek Road intersection.

He also argued the speed limit should be reduced to 60 km/h.

The panel now has until mid-April to report its findings to VicRoads. The acquisition must eventually be approved by Planning Minister Matthew Guy, and the project is yet to receive funding. VicRoads network planning director Robert Freemantle declined to comment before the findings were received.