Late last week, the Illawarra Business Chamber and the NRMA released Upgrading Road Connectivity between the Illawarra and Greater Sydney, which called for upgrades to the M1 Princes Motorway and Picton Road.

It also touched on a new linkage between Picton Road and Mt Ousley.

Called the Mt Ousley to Picton Road Connector, it would start just northwest of the new Mt Pleasant Road overpass and link up to Picton Road at the intersection with Mt Keira Road.

“The alignment would have a length of around 3.3 kilometres with an average grade of 6 per cent,” the report stated.

“Most of the alignment would need to be in tunnel. The route would be around four kilometres shorter than the current access to Picton Road.”

Costs are estimated to be as much as $1.6 billion.

“The connection of the proposed tunnel into Mt Ousley would provide significant engineering challenges and high costs,” the report stated.

The report identifies the tunnel as a “conceptual solution” to reduce access time to Picton Road and as an option to consider in investigations for a second crossing of the escarpment.

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The need for another crossing has been a part of government planning for several decades, both to relieve pressure on the motorway over Mt Ousley and to provide an alternate route if that road becomes blocked.

The IBC-NRMA report recommended these investigations should look at options that also exclude Mt Ousley.

“Between 1996 and 2006, Roads and Maritime Services studied several options for a road crossing of the Illawarra escarpment, including options to upgrade Bulli Pass (in 1996), with alternative alignments that removed the hairpin bend,” the report stated.

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“However, no alignment could be identified to reduce the grade to less than 10 per cent, which was considered to be too unsafe to be feasible.”

Rixons Pass Road and a crossing north of Mt Kembla have also been considered.