About 40 properties will be fully or partially acquired and 74 hectares of native vegetation bulldozed for construction of a $1.8 billion motorway to the new Western Sydney Airport.
Construction of the 16-kilometre M12 motorway is due to start in 2022 and be completed by 2025, about a year before the $5 billion airport at Badgerys Creek is scheduled to open.
The estimated cost of the project has already risen by more than $400 million to $1.8 billion due to an increase in land values around the site of the airport.
The M12 motorway will offer motorists a direct link to the new airport at Badgerys Creek.Credit: Peter Rae
The federal government included an extra $405 million for the motorway in the Budget in April, taking its funding to $1.45 billion. The remaining $350 million for the M12 will come from the state government.
The Herald revealed in January that the state's transport agency had been investigating options to either reduce the scope of the project or secure extra funding after putting the cost at $1.38 billion – $130 million above what had then been committed by the two governments.
The state government released an environmental report for the M12 on Wednesday that showed 36 properties will be partially acquired, and five fully, for the motorway. Most of the properties are farms or orchards. Temporary leases of land will also be needed during construction.
The report says about 74 hectares of native vegetation is expected to be dug up for the motorway, including about 1.85 hectares of an existing bio-banking site within Western Sydney Parklands. The state's bio-banking scheme is intended to offset the loss of biodiversity, including threatened species.
In all, the project is set to impact about 90 hectares of land within the 5280-hectare Western Sydney Parklands, including bush land, walking tracks and the Wylde mountain bike trail. The state's roads agency is working with the trust overseeing the parklands on a replacement mountain bike trail.
Penrith City Council mayor Ross Fowler said the route chosen would probably have the least impact of those considered for the M12 motorway over the past few years.
"It was always going to have an impact somewhere and hopefully this is the one that has the least impact on the population," he said. "It is a much needed piece of infrastructure."
The new motorway, which will be two lanes in either direction and not be tolled, will link the M7 at Cecil Hills to the Northern Road at Luddenham and offer motorists direct access to the airport.
While traffic on roads in the wider area will generally be improved as a result of the project, the report said the motorway may lead to an increase in travel times for motorists on the M7 motorway in the morning peak, mostly due to extra vehicles merging from the M12 at an interchange.
"This merging would generate localised delays, particularly in the northbound direction," it said.
Travel times on the Northern Road from Elizabeth Drive, northbound to the M4 motorway, will also increase due to motorists driving from Western Sydney Airport using the M12 and the Northern Road to travel north in the evenings.
Western Sydney's population is forecast to rise from two million today to three million by 2036 – or an average of 50,000 extra residents each year – which will pile pressure on roads such as the M12 and other transport in the area.
NSW Planning Minister Rob Stokes said the state was working with the the federal government to ensure that road and transport infrastructure was in place to better connect the region to the rest of Sydney before the first plane takes off at the new airport.