Sydney's massive WestConnex motorway project is underway with an environmental impact statement to be made public early next year.
The NSW government says it awarded a tender to prepare the environmental impact statement (EIS) for the project's M4 widening stage to "a joint team from SMEC/RPS".
"The awarding of the first major tender follows the approval of the WestConnex business case late last month and the lodgement of the M4 Widening planning application," Premier Barry O'Farrell said in a statement.
"This is a game-changing project for western Sydney and I'm delighted with the enormous momentum that is now behind the project."
Mr O'Farrell said the EIS for the M4 widening would be exhibited for public comment in early 2014.
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He said the main construction industry briefing for all three stages of WestConnex would be held later this month.
The $11.5 billion network of motorways and tunnels will link the city's west and southwest suburbs with its port, airport and CBD.
Construction on stage one, which involves widening the M4 between Parramatta and Homebush and extending the motorway to Haberfield via tunnels, is set to begin in 2015, with the whole network due for completion in 2023.
