The 92-year-old Junction Bridge is one of only 44 bridges built in NSW between 1905 and 1936 using the rare Harvey Dare truss structure design, which has "the highest survival rate" of the truss style according to Transport for NSW (TfNSW).

Upper Hunter MP Dave Layzell said the Junction Bridge provided an important link for the local community and rehabilitation works were needed to ensure it continued to give safe and reliable service into the future.

"We will be replacing the bridge decking and sealing the bridge deck, rebuilding the abutments and repainting the timber elements to give it a new lease on life," Mr Layzell said.

"With these works Transport for NSW is looking to increase the capacity of the bridge, providing benefits for primary industries in the area."

NSW Minister for Regional Transport and Roads Sam Farraway said Junction Bridge was previously owned by the Upper Hunter Shire Council but its ownership and maintenance was transferred to TfNSW in July 2020.

"The opening of this bridge in 1930 would have been momentous for the local community and it is great that it will continue to play a pivotal role in keeping them connected," Mr Farraway said.

Restoration work on the bridge is expected to be completed by mid-2023, weather permitting, and TfNSW said there would be changes to traffic management during that time.

TfNSW said it will endeavour to maintain alternating traffic flow arrangements during the day works, but some bridge closures might be required on occasions, with traffic to be diverted to a temporary side road.

"We're upgrading the existing side road so people will continue to have access at all times until work is complete in April next year, weather permitting," Mr Farraway said.