The road will remain closed over the weekend and the Waitaki District Council will investigate whether warning lights were active in the moments before impact.
A Fire and Emergency New Zealand (Fenz) spokesman said two appliances from the Oamaru station responded after a truck rolled on to its side in Humber St about 12.40pm yesterday.
The driver did not need help to get out of the truck, the spokesman said.
A St John spokesman said that an ambulance and an operations manager treated a patient for minor injuries at the scene.
A KiwiRail spokesman said the truck had hit a rail overbridge. The bridge was checked for damage and reopened to trains at 2.30pm. No rail services were affected.
Council roading manager Mike Harrison said it had been suggested
warning lights on the approach did not activate immediately and that would be investigated.
The bridge had Waka Kotahi NZ Transport Agency standard height warning markers that were visible from both directions.
The road was expected to be closed until at least Monday, Mr Harrison said.
The overbridge has been the site of several truck crashes over the years.
One in November 2020 followed height clearance signs being lowered to 3m from 3.6m.
It was the third such crash at the bridge in an 18-month period.
In 2014, a truck transporting cars hit the bridge, causing its cargo to spill on to Humber St.
NZTA data shows truck crashes at the site in 2006 and 2008.
— Additional reporting Nic Duff
