Broughton Pass is still on track to open by July with the final stages of the repair work under way.
The bridge was closed to the public in June last year when the approach to the bridge sustained significant damage in a heavy storm.
Wollondilly Council’s infrastructure and environment director Michael Malone said the bridge would be opened by July, weather permitting.
“There is no doubt the council is very keen to reopen the road as soon as possible so we can reconnect the communities of Wilton and Appin,” he said.
“The council and the experienced contractor Pan Civil will put in all efforts to reopen the road by July.
“We do get the frustration – it is an hour’s drive round and even our own employees have to make that trip.
“It is in all our interest to open the bridge as soon as possible.”
Mr Malone said the project was progressing well.
“Unstabilised sandstone material is used as structural fill [in the pit],” he said.
“It is combined with terramesh and re-enforcing rods, which run north to south and east to west in the pit.
“The rods are attached to the rock and act as anchors to form a reinforced earth structure.
“That structure is not attached to the bridge. It is a self-contained structure that abuts the bridge. That way no pressure will be put on the bridge.”
Mr Malone said there was about two metres of fill to go before the approach slab was finished.
The concrete slab will then be poured and covered with a wearing course – either asphalt or spray sill.
“Guard rails on the approach and on the bridge will also be installed and some concrete repairs on the bridge will also be completed,” Mr Malone said.
He said the council would also remove dangerous trees near the bridge, repatch the asphalt on the Appin side and repair drainage issues.
“We are taking advantage of the road closures by fixing other issues on the road,” he said.