The Auckland Westpac Rescue Helicopter responded after reports that a male patient was struggling in the water around 4pm.
Hot Water Beach Lifeguard Service chairman Gary Hinds said the service was packing up supplies after a day of training on the other side of the beach when the incident unfolded.
They were not notified of the emergency callout until six or seven minutes after Fire and Emergency New Zealand.
"We need to be there as soon as other people. If we get stood down that is fine, but 7 to 8 minutes, in a life-saving situation, is crucial."
A similar incident unfolded two weeks ago where there had been a near drowning on the beach, the service was only aware of the callout when the fire truck responding personally called Hinds to alert him.
Hinds wanted to receive the message of a callout at the beach as soon as other emergency services did. It was something he had been fighting for a long time, he said.
"I've been working on this for four or five years. We are like the poor cousins, we have the same training and assets and we are the ones at the beach and know it well.
"It is disappointing, we don't know if we could have changed anything, we have to sort this out so it doesn't keep happening."
A police spokesperson said the man's death had been referred to the coroner.