Plunket is reminding people to supervise children around water at all times, while Water Safety NZ has set a target of no drownings over the holidays.
Plunket's warning came after a man was discharged without conviction last week after his 17-month-old baby drowned in a swimming pool on Christmas Day 2014.
In sentencing James Mataafi, Justice Peter Woodhouse said seven adults were there that day and it was assumed someone was supervising the children swimming outside the Manurewa home.
Plunket's safety adviser, Sue Campbell, said supervision of young children is critical, as they are attracted to water and can get into trouble quickly.
"At this time of year when there are lot's of activities - family gatherings or getting together with friends and you might be around a beach or a river or even a pool at home - it's very important to mainly set up a roster whereby an adult will always be watching the children.
"And you can take turns so it doesn't have to be an arduous thing and you can make it fun by having fun with the kids."
Ms Campbell said young children were attracted to water and could get into trouble quickly.
She said it was encouraging that statistics were showing drownings and hospitalisations of young children are down.
Meanwhile Water Safety New Zealand was aiming for a target of zero drownings for the Christmas holiday period after last year's toll of 10 deaths, up from an average of seven.
The official holiday period began yesterday at 4pm and runs until 4 January at 6am.
The organisation's chief executive, Jonty Mills, said the target was zero this time.
He said there was a new social media campaign was targeting the at-risk group of young men by using a character with a scythe called the Swim Reaper.
"We can use what we call geotargeting to actually target these young Kiwi males at the point where they are making some often bad decisions," he said.
"And there's certainly some high-risk locations like Hunua Falls and parts of Northland."