Congestion on the rail line to Sydney could be so bad in just over a decade that freight trains will barely be able to use it.
This raises the spectre of a massive increase in truck traffic on the region’s already choked key roads.
This is the shocking scenario contained within a Transport for NSW business case for the Maldon Dombarton rail line – a report the government has kept hidden since it was completed in June 2014.
The business case recommends the construction of the freight rail line, including the four-kilometre Avon Tunnel, two railway bridges and three road bridges.
If the Maldon-Dombarton is not built, the report puts forward a scenario that the growth in passenger trains by 2031 would make the rail line so congested that freight companies could basically forget about using it.
“Post 2031, a significant enhancement in passenger train service frequencies is proposed on the Illawarra Line, most notably between Hurstville and the city,” the business case said.
“Assumptions made by Transport for NSW have assessed the impact of these additional services would reduce future rail freight capacity to eight paths per day with freight operations confined to night times only when passenger services are assumed not to be in operation.”
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The business case acknowledges this scenario “was not considered a feasible alternative”.
The document was released through a freedom of information request from Wollongong MP Paul Scully – though only after he appealed the departmental refusal to make it public.
“It’s a damning assessment of the capacity of the region’s infrastructure,” Mr Scully said of the business case, “and provides very clear warnings that unless the Maldon-Dombarton rail project is started and completed, freight transport to and from the Illawarra will simply grind to a halt in as little as a decade.”
The report also shows how quickly the cost of building the line increases while governments delay construction.
A 2011 report for the federal government estimated the project costs at $470 million.
In 2014, the NSW government business case put that cost at $701 million – a 49 per cent increase in just three years.
The business case also states $105 million would be required to improve the line between Coniston and Unanderra.