Paynes Crossing Bridge will be replaced with a two-lane bridge in a project that is designed to improve access and safety for road users, including Rural Fire Service tankers and tourist buses.

The bridge is jointly owned by Cessnock and Singleton councils and provides a vital rural link between the two LGAs, crossing Wollombi Brook 11.6 kilometres north of Wollombi.

The single-lane, weight-limited timber bridge has deteriorated due to time, heavy traffic and storm damage.

The new bridge, to be built adjacent to the existing structure, will have an improved alignment and will be three metres higher than the existing deck, to increase access during flooding.

A $3.1 million project, it has received $667,000 from the Federal Government's Bridges Renewal Program and $668,300 from the NSW Government's Fixing Country Roads Fund, with the two councils to contribute the remainder of the funds.

Cessnock mayor Bob Pynsent welcomed the start of works this week.

"Payne's Crossing Bridge is located on the Cessnock and Singleton council boundary. This is an important access point for residents and people visiting both our wonderful local government areas," he said.

"It's fantastic we can collaborate with our neighbours to deliver this vital infrastructure.

"The upgrade is good news for the community as it's expected to bring new opportunities for both freight and tourism.

"The safety of residents during the fire season will also improve as a Rural Fire Service tanker will be able to cross the bridge to protect people, homes and property."

Singleton mayor Sue Moore said the long-awaited project would deliver considerable benefits to local residents and visitors to the region.

"It's been a particular concern that Rural Fire Service tankers had difficulty providing adequate fire protection in the area due to access limitations as a result of the load limit, and the load limit also had significant implications for tourist bus access," she said.

"I'm looking forward to the opportunities the new bridge will open up for people coming in to our area, particularly as we're working hard to promote local businesses and tourism."

A Cessnock council spokesperson confirmed that the old bridge will remain open until the new bridge is constructed, meaning no road closures will take place during the project, although some traffic disruptions and delays may occur.