A truck carring a 64m-long wind turbine blade has tipped on its side along State Highway 45 in Taranaki.
The truck slid into a ditch and tipped over shortly before 8am while negotiating a bend at the intersection with Hamption Road, south of Ōkato.
NZTA said one lane had been reopeneded on SH45, and a stop-go was in place.
A contractor has been called to lift the trailer out of the ditch.
The blade was being transported from Port Taranaki to the Waipipi Wind Farm near Waverly in South Taranaki.
It was due to leave the port at 3am and arrive at Waipipi about 8am.