Minister for Regional Transport and Roads Paul Toole said the 13-kilometre section of upgraded track would cater for trains carrying up to 25-tonne axle load, increasing their capacity by more than 20 per cent and opening up higher speeds of 80 kilometres per hour along sections of track.

The Manildra Group, one of the state's biggest manufacturers of flour and grain products whose processing plant is based at Bomaderry, made the successful submission to upgrade the line under the NSW Government's $400 million Fixing Country Rail.

"Current axle load restrictions prevent 60-foot-long wagons from utilising as much as 33 per cent of their container capacity," Mr Toole said.

"When you factor in the combination of 40 and 60-foot wagons in use, it equates to a capacity loss of more than eight per cent for export volumes travelling from Bomaderry to Port Botany.

"Enabling freight trains to carry heavier loads will not only improve freight efficiencies, but it will also help free up currently idle freight capacity on the line and improve the reliability of passenger services."

Mr Toole said the upgrade is a huge win, allowing an extra 350,000 tonnes of freight into rail and take more than 10,000 truck movements off the road each year.

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Manildra national transport and logistics manager Mark Owens said the project would cut delivery times, allow more goods to be transported by rail and reduce costs for both manufacturers and consumers.

"These upgrades will improve rail capacity between the South Coast and our ports, and in doing so, significantly increase the efficiency and amount of freight we are able to move by rail," Mr Owens said.

The upgrade created 140 jobs and includes four tunnels, totalling about 1.2 kilometres in length, with 25-tonne axle load track and concrete sleepers.

Crews cleaned about eight kilometres of ballast, laid more than 10km of track, installed almost 400 new concrete sleepers and upgraded 700m of the four tunnels.

The project was funded under the NSW Government's $400 million Fixing Country Rail which is delivering projects to support, reinvigorate and upgrade important regional rail freight infrastructure throughout NSW.

Fixing Country Rail has already seen more than $229 million rolling out across 51 projects across regional NSW.

For more information, visit www.transport.nsw.gov.au/operations/freight-hub

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