As of January 5, 25 people had drowned since the beginning of December — equal to the total for all of last year's 2020/21 summer, with nearly two months to go.
In recent weeks there have also been several deaths.
Last Saturday, a snorkeller died after a water incident in the Coromandel.
Water Safety NZ chief executive Daniel Gerrard said the level of drowning was "unprecedented" and described it as "horrendous".
"I'm at a loss on what to say," he told the Herald.
"I'm just horrified at the level of drownings. It's just an absolute shocker."
Fourteen people died in the country's waterways over the Christmas New Year period just past – the highest number in 25 years.
Water Safety NZ Chief executive Daniel Gerrard said there had been 18 preventable drownings so far this year, a quarter of last year's total in less than a month.
This time last year, there had been eight.
Gerrard said their data so far had shown "older guys behaving badly" was the area they needed to focus on.
"They're a difficult group to engage with, but it's really about being out there with your mates and not being 'that guy' that does the foolish thing," he said.
"[We need to get] any messaging we can to those guys to stop and think about their family, about their friends, before they jump in, or turn the motor on the boat.
"It's often not seen as risky behaviour – it's overestimating your ability and underestimating the conditions."
He was not expecting any fewer people on the waterways this long weekend, even though New Zealand was now at the red light setting because of the spread of Omicron.
Findings from the 2021 statistics showed 84 per cent of the drowning victims were male, and 96 per cent of the Māori drowning deaths.