SH 1 closed after truck and trailer rolls

A truck and trailer unit has rolled on State Highway One at Mangamuka in Northland. 

The road is completely blocked and will not re open until midday today. 

Diversions are in place as follows:
The road is closed just before the Mangamuka Gorge. 
Traffic for both directions should use Broadwood Road to Awaroa Road.
 Then Kaitaia-Awaroa Road through Herekino onto Kaitaia via the coastal route.
Traffic control personnel will be present to assist.