State Highway 30 near Benneydale is down to one lane after a logging truck overturned.
A police media spokeswoman said the crash happened about 9.15am, near Mangaokewa Rd.
The logging truck crashed into a ditch and overturned, spilling "a few logs" across the road, she said.
The driver, the sole occupant of the truck, was not injured.
The NZ Transport Agency said a detour was originally in place via Mangaokewa Rd but it was suitable for light vehicles only.
