State Highway Three has been reopened after a truck and trailer carrying detergent rolled this morning between Waverly and Whanganui.
The 30-year-old driver was not injured but was taken to hospital as a precaution.
Sergeant Andy Anderson said it appeared the driver had lost concentration while turning a corner and rolled the truck.
It was possible he had fallen asleep but investigations are continuing.
State Highway 3 near Nukumaru was closed for several hours from 6:45am until police set up a one-lane diversion through paddocks at a nearby marae.
A Taranaki Daily News reporter at the scene said the traffic was backed up for about 2km in both directions from the crash.
A crane was used to clear the road about 1pm.
The truck had a hazardous-chemical warning sign but police said it posed no immediate risk.
- Taranaki Daily News
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