"He said 'mum I've been in an accident', he told me he was fine but the car was totalled.
"That's a long way down, they're very lucky to be alive, it could have been a whole lot worse," she said.
An ambulance spokesperson said the two people were lucky not to have been seriously injured. He said the driver, Mr Campbell, complained of a sore shoulder but his passenger was uninjured. The pair were taken to Tauranga Hospital for observation.
Firefighters, ambulance officers and police attended.
Mrs Campbell said she was grateful her son was driving a "sturdy" car. "The mini ... saved their lives. If it was any other car they'd be squashed."