Six families mourned six people who died by drowning over the official holiday period - two more water-related deaths than this time last year.

Water Safety New Zealand has released the preliminary figure for the preventable fatal drowning toll over the official holidays, which ran from 4pm on Christmas Eve to 6am on Friday.

The deaths include that of a man who got into trouble while crab fishing at Uretiti Beach, south of Whāngārei, about 10am on Christmas Day.

He was pulled from the water at 12pm.

A few hours later, about 3pm, a person died while snorkelling at Kai Iwi Lakes, north of Dargaville.

On Boxing Day, a 60-year-old swimmer died at Onemana Beach - 10km north of Whangamatā.

The next day, a woman in her 60s died after a boat capsized in the Houhora Harbour, in the Far North. Emergency services were called there just after 11am.

On New Year's Day, a 70-year-old man drowned near a boat ramp on Beach Rd, in Whangamatā, at 3pm.

The sixith victim was aged over 65 and in Auckland. No other details are known about the victim or incident.

Water Safety NZ chief executive, Jonty Mills, said: "Every one of these preventable deaths is devastating for a family and a community and has real and profound impact on many people's lives.

"It has also been another busy holiday period for our frontline services, which indicates the toll could have easily been much worse."

OVERALL DROWNING DEATHS IN 2019:

A total of 78 people died by drowning last year, provisional figures from Water Safety NZ showed.

The highest number of drownings happened in Auckland - where 17 people died - followed by 15 drownings in the Northland region.

In 2018, a total of 68 people died by drowning around New Zealand. That was the second lowest number of drownings recorded since 2010, when 64 people drowned.

In 2017, a staggering 92 people drowned that year.

This year's statistics showed that a number of the drownings happened when people were alone, Mills said.

That emphasised how important it was to take a friend or buddy when heading out on the water.

"While our waterways are our playground, they can be incredibly unforgiving and need to be treated with respect," Mills said.

Some of the key safety messages Water Safety NZ highlighted including swimming between the flags at patrolled beaches and having an adult actively watching children around water at all times.

People out swimming should also always look out for rips. Those heading out on boats need to be wearing lifejackets - as does anyone fishing from rocks.

Boaties and paddlers are also encouraged to take two waterproof forms of communication on their person.

"Remember the water safety code: Be prepared, watch out for yourself and each other [and] be aware of the dangers and know your limits."