Work to duplicate Knox Road and the overhead railway bridge at Doonside is nearing completion but also causing major traffic delays.
The duplication is expected to be completed on the $10 million project by April 2013, a Blacktown Council spokeswoman said.
The project to upgrade and widen Knox Road is in the final stages, which includes the duplication of the bridge, road construction between Cross Street and Eastern Road, new street lights and traffic signals at the intersection of Knox Road and Eastern Road.
Long delays have been experienced by motorists on Eastern Road as construction work centres on the roundabout.
The spokeswoman said the council ‘‘thanked motorists for their patience’’.