Enquiries into the accident were continuing and a decision over whether to prosecute the driver would be made at a later date, he said.
The truck, owned by New Zealand Vehicle Deliveries Transport Ltd (NZVD), had minor damage to its trailer.
The bridge was inspected by KiwiRail structural inspectors from Dunedin but appeared to be unscathed.
The three damaged vehicles and two others were cleared by 1.30pm with help from the New Zealand Fire Service and a forklift driver from a nearby business, Mr Paterson said.
PTS Logistics, NZVD's parent company, declined to comment on the crash last night.