A man was rescued after more than half an hour in the Tamaki River yesterday.
Coastguard northern region duty officer Mark Leevers said they were told about the emergency at 5pm, but stood down before arriving after another person intervened.
Riverlea Ave resident Anna Jorgensen called police after seeing the man swimming between yachts moored in the Panmure Basin river.
"His dinghy was drifting away and he couldn't get to it," she said.
Jorgensen became worried after he spent more than half an hour in the water. His dinghy floated to shore and was used by another person to rescue him as he clung to a yacht.
