A person drowned every three days this summer at New Zealand beaches, says Water Safety New Zealand.
Of the 40 who died, 11 people drowned while swimming, up from seven swimming-related drownings the summer before, the organisation said.
Though rivers were traditionally the spot New Zealanders drowned at most, beaches took the lead this summer with 12 drownings - double the number year before.
Six people drowned in rivers.
Water Safety New Zealand's CEO Matt Claridge said the number of deaths this summer was down from the five-year average of 41, but the number was still "alarmingly high".
"It's promising that we're seeing a downward trend but the number of drownings still occurring in this country is disproportionately high," he said.
The number of deaths this summer was still around 30 per cent more than Australia's summer season toll on a per capita basis, Claridge said.
He said the high number of drownings could be related to the long stint of hot summer weather, meaning more people went to the beach.
However, it still showed people were not paying attention to water safety basics.
Claridge said males made up 81 per cent of the total summer drownings with the vast majority of those that drowned in either the 15-24 or 45-54 age groups.