"Had this happened outside the harbour, I'd hate to think what would have been the likely outcome."
Emergency services were alerted about 7pm. Police Search and Rescue, Whangarei Coastguard and the Marsden Point Oil Refinery emergency services boats were all called out, and St John Ambulance and the Whangarei Heads Fire Brigade were also called for assistance.
The group left Urquharts Bay and were fishing around the channel between the gun emplacement and Busby Head.
Mr Metcalfe said it took about an hour to rescue the group, who were located ashore on the rocks underneath the gun emplacement.
"Ultimately, a lot of people were involved for an incident that never should have happened," he said.
All five managed to walk back to the end of the road at Urquharts Bay, where they were checked by ambulance staff.
A male and female, both aged 22, were treated by ambulance, as they were "extremely cold" and "more so" at risk of hypothermia, according to St John Northland district operations manager Tony Devanney.
One of the two also had a minor foot injury, the others were fine and no one was taken to hospital.
Mr Metcalfe said anyone in the water would have struggled to stay alive for any length of time.
"Even when they managed to get ashore, the risk of hypothermia was still very real due to wet clothes and cold air temperature," he said.
Mr Metcalfe said the near-tragedy was a reminder that people needed to be well prepared when they went boating, by having lifejackets for everyone on board, ensuring the engine was in working order and having at least two forms of communication.
"To me, don't have five adults in a 3m boat at any time.
"They were risking their lives," he said.
