Update, 6.18pm: Both northbound lanes of the highway are now open at Croom, but the on-ramp is still closed
Earlier: A man has been taken to hospital and the Princes Highway is partially closed northbound following a truck crash at Croom.
The truck overturned about 3.30pm on Tuesday, at Shellharbour Road.
Paramedics treated a man aged in his 40s at the scene for leg injuries before taking him to Wollongong Hospital.
One of the two northbound lanes remains closed, as does the on-ramp heading north.
Instead of taking the on-ramp, motorists are advised to take Shellharbour Road, Lake Entrance Road, and New Lake Entrance Road to join the Princes Highway.
There is heavy traffic stretching along the highway from Kiama Downs to Croom.
It is understood the truck was carrying blue metal, a construction aggregate.
Police and Fire and Rescue NSW were also on scene.
It was the second truck crash of the day in the Illawarra - another driver was left with serious head injuries after he crashed on the M1 Princes Motorway at Spring Hill.
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