A man who tried in vain to save a young boy who fell from an Auckland wharf has joined water safety advocates in pleading for vigilance this summer.
The death of 5-year-old Haoran Chen, on November 11, came amid a year in which twice as many Aucklanders died in preventable drownings than the year before.
But the spike, revealed in new Water Safety New Zealand figures, was also observed elsewhere in the country, and has been partly put down to warmer weather over past months.
There was also a concerning spike in the preventable drownings of Kiwis over 65 - and those 5 and under.
Bayswater man Bernard Riedl almost drowned himself while trying to rescue Haoran, who fell into choppy waters at Torpedo Bay wharf, near Devonport.
"I didn't appreciate it before it happened to me, but that's the thing - one minute you are safe by the sea with your family, and next minute someone you love is drowning, or you are drowning yourself."
Water Safety New Zealand statistics showed Auckland's preventable fatal drowning rate jumped to 22 in 2017, double that of 2016.
Before that, the rate had been static for the previous four years.
The startling leap was among higher rates of drowning in many other regions, over a year that saw 88 such cases and a 13 per cent increase across the country.
It comes after several incidents since the start of the year.
A week after former soldier Wairongoa Clarence Renata died at Northland's Cable Bay after going into the water to save five children caught in a rip, Taupo woman Amy Jenny Brown, 35, drowned on January 9 while trying to save a child at Haumoana Beach in Hawke's Bay.
Water Safety New Zealand chief executive Jonty Mills said 2017's higher figures could have been partly due to hotter temperatures recorded over the last part of the year.
"There is an obvious connection between drownings and the weather. We've seen a spike from October related to the early onset of summer."
But New Zealand's drowning problem was nonetheless a complex one, he said.
"We have a very diverse and growing population with very high participation rates across a wide range of different activities and aquatic environments."
In Canterbury, nine people drowned compared with one in 2016, with increases also recorded in Wellington (eight to one), Bay of Plenty (12 to seven) and the West Coast (six to three) - the region that also had the highest rate per 100,000 population.
Marlborough, where three people drowned last year, had the second highest such rate, ahead of Gisborne, Southland, Bay of Plenty and Northland, with rates at around four per 100,000 of population.
Of those who died in preventable drownings, seven were toddlers - four more died than in 2016 - while the number of people aged over 65 also doubled from eight to 16.
"For under-5s the only solution is constant active adult supervision. Also, we are living longer, healthier lives and retirees are more active, so there is extra risk."
The majority of victims were Pakeha (48), with 15 Maori, 11 Asian people and six Pacific Islanders.
There was also a sizeable increase in the number of females who died, rising from 11 in 2016 to 19 last year.
"Historically a male problem, female drowning fatalities have almost doubled in 2017, a reflection of higher female participation rates across a wide range of activities."
Around home environments, seven drownings occurred in baths, eight in home pools and three in ponds, while two occurred at public pools.
Eleven people drowned far off coasts - nearly twice as many as in 2016 - while nine died in lakes, when none did the year before.
But the number of people who drowned in rivers nearly halved - 13 in 2017 compared with 23 in 2016 - and the number of beach fatalities fell from 21 in 2016 to 14 last year.
There were fewer cases of people drowning while swimming or aboard large boats, and no cases of deaths following dives or jumps, but there were increases in tragedies involving free diving, angling, scuba diving, shell-fishing, snorkelling, small boats, and "accidental immersions".
"These are people who ended up in the water when they had no intention to," Mills said.
Further, while there was a general significant increase on 2016's nationwide figures, said the longer-term pattern appeared more positive.
An analysis of five year rolling averages indicated a "plateauing" of preventable drowning fatalities against an increasing population, high tourism and immigration, and growth in recreational activity, he said.
Mills said New Zealand had some of the most magnificent beaches, rivers and lakes in the world, and being around water was part of the "quintessential Kiwi lifestyle".
"With any water comes risk and sadly every year far too many people lose their lives or are injured in, on or around the water.
"The tragedy is that most drownings and injuries are preventable.
"As summer continues we know Kiwis will continue to get out and enjoy our beautiful waterways but we need all Kiwis to take responsibility and think about water safety.
"Remember the water safety code. Be prepared, watch out for yourself and each other, be aware of the dangers and know your limits."