A total of $1.4 billion has been set aside for North-South Road corridor projects.
That includes $177 million for upgrading the Pym Street to Regency Road stretch between Gawler and the River Torrens.
The government hopes it will increase freight movements and reduce travel time.
As expected, the state will receive $220 million for the electrification of the Gawler rail line.
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"Current services on the Gawler rail line are reaching capacity and will be unable to support future demand," budget papers say.
The federal government has also allocated $160 million for the Joy Baluch bridge in Port Augusta.
WHAT'S IN THE BUDGET FOR SOUTH AUSTRALIA
* $1.4 billion for the North-South Road corridor projects, including $177 million for the Regency Road to Pym Street
* $220 million for electrify the Gawler rail line from Salisbury to Gawler
* $160 million for the Joy Baluch bridge
