"If they were to repair Evans Pass (Sumner Rd) they wouldn't have so far to go to get into Christchurch [from Lyttelton]. The only way they can travel is around through Gebbies Pass and until that road is rectified we may even be looking at more of this kind of thing happening."
Senior Constable Flynn said it had been fortunate the truck did not roll off the road and down into the gully below the road.
"I think they were extremely lucky to come to rest the way they have. Much more and they would been completely tipped over."
The investigation was yet to be completed but early indications were that no charges would be laid over the incident.
Witness Nicky McCaughan was cycling with three friends when the "surreal" drama unfolded, as the truck tipped just 10 metres in front of her.
"I was biking past going up the hill and he was coming down the hill to turn the corner but in order to do that he had to come right across the other side of the road so we sort of had to go off the road to allow him to be able to do that," she said.
"He was just coming down, taking it very slowly and coming right round the corner and the bend was too sharp and too steep [of an] incline. The whole back trailer just went flip and his cab just went bang, poor guy."
Mrs McCaughan said she spoke to the driver after he climbed free from the cab and he told her he had taken trucks with big long trailers around that stretch of road before and they had come close to tipping over.