Coastguard’s National Operations Centre said three people tipped into the water when a craft overturned on the Rangitīkei River bar at Tangimoana, a coastal settlement about 15km southwest of Bulls.
One person made it to shore. A second was found on the beach, and the third was brought in by Coastguard volunteers.
It was the first of two tragedies at the settlement in a month.
Ryder Hayden Coley-Clark, 7, from Whanganui, drowned last Friday after he and another person were swept out to sea.
Cara Barron, principal of Churton School in Whanganui, told the Herald it was an “incredibly difficult time” for the school community.
“We are deeply saddened by the loss of one of our students.
“We are supporting our tamariki and staff while respecting the wishes and privacy of his whānau.”
In a Givealittle post, his family described Ryder as an “awesome kid full of life” who was taken way too soon.
Police said the person with Ryder made it back to shore unharmed.
Officers worked at the scene alongside Hato Hone St John, the New Zealand Defence Force, Coastguard Manawatū and Coastguard Whanganui volunteers, Surf Life Saving New Zealand and members of the public.