Emergency services were called to Shell Waikouaiti at 11.20am, following reports a truck had driven into the service station's canopy.
Truck driver Earl Shannon, of Bluff, told the Otago Daily Times he used the service station up to three times a week, but had never hit the "bloody building before".
The 4m high Hino truck had clipped the corner of the station's canopy, tearing it from the building, smashing windows and causing minor damage to one petrol pump.
No other vehicles were in the forecourt at the time, and the two attendants were inside the building when the incident occurred.
Owned by Ngai Tahu Seafood, the refrigerated truck contained two tonnes of live crayfish destined for export. The cargo, estimated to have a value of $200,000, was undamaged and the truck continued its journey to Christchurch.
A Ngai Tahu Seafood spokeswoman said the company was investigating the incident.
Constable Jon-Paul Tremain, of Waikouaiti, said the driver had misjudged his entry into the service station, and the accident had the potential to be much worse, given the large supply of flammable liquid.
Police were still investigating, but charges were likely.
Jonathan Hill, of Greenstone Energy, the company which owns Shell's New Zealand operation, said the site had been extensively damaged, and there was every likelihood it might not reopen.
The neighbouring premises of Hawkesbury Motors was unaffected.
Two forklifts were supporting each end of the service station canopy yesterday.
"We have some very serious concerns over the structural integrity of the shop," Mr Hill said.
"It is in a pretty bad way. We will make a decision over the next little while on the future of the site."
The company was working to redeploy the service station's six staff.
Some were expected to work at the refurbished station in Palmerston.
