A memorial service marking the fifth anniversary of the Whakaari/White Island eruption will be attended by 33 survivors and family members, including Australian Jesse Langford, whose mother, father and sister died that day.

The families will then get the first private viewing of the design for a memorial at a riverside location that is yet to be determined, to honour the 22 people who died in the eruption on December 9 2019.

Mark Inman, whose tour guide brother Hayden Marshall-Inman's body has never been found, said Monday would be a day of reflection.

"We do one thing every ninth [of the month] now. We actually go out to Whakaari and we hang out there and say hi to my brother and just sit in the bay and remember, and just think about all those good times that we used to have.

"But we also reflect on life that's sort of carried on without him and we think about all those others that lost their lives as well."

Inman said he and his family, along with other family members of victims, would head to the island off the coast of the Eastern Bay of Plenty at dawn on Monday.

Hayden Marshall-Inman's body was never found. Photo: RNZ / Dom Thomas.

At the same time, a karakia - open to the public - would take place at Te Hau Tutua Park.

Ngāti Awa would lead the karakia, as it had done each year since the tragedy, but iwi liaison Joe Harawira said all faiths would be included in the prayer ceremony.

Harawira said the main aim was to be inclusive, to make the visitors feel like they were part of a wider family and community that would never forget the events of 9 December 2019.

"Because we've made a commitment, the (Whakatāne District) Council and Ngāti Awa to, every year, remember this particular occasion."

Forty-seven tourists and guides were on the island - which was at alert level 2 for volcanic activity - that day. It began erupting at 2.11pm.

Of the 25 who survived, all suffered burns, including Langford, who was 19 at the time.

The 33 survivors and family members attending on Monday are from New Zealand, Australia and Britain. They are understood to be the biggest contingent to attend in the five years since the eruption.

Family members of some of the Australian victims of the eruption at the 2022 service marking the third anniversary of the disaster. Photo: Troy Baker.

At noon, the families, along with dignitaries including Emergency Management Minister Mark Mitchell, Police Commissioner Richard Chambers and Whakatāne mayor Victor Luca, will meet at Te Mānuka Tūtahi Marae for a pōwhiri.

At 2.11pm there will be a minute's silence followed by speeches, after which the families will be given an opportunity to speak.

At 4pm, a design for a new memorial at the heads will be unveiled by Harawira's brother, sculptor Peter Harawira.

Joe Harawira said the drawing was fantastic.

"It's a beautiful idea. It's a beautiful concept."

Inman said he had already begun fundraising efforts for the memorial starting with a golf tournament on Friday, and a concert featuring Kora, Joel Shadbolt of LAB, and Maisey Rika among others on the weekend.

Inman had so far raised $160,000 for first responders on the day including the Coast Guard, the Whakatāne Fire Brigade, Burns Unit, and St John Ambulance.

He said the families would be having a quiet Sunday in the build-up to Monday, which he described as an emotional day.

Victims of the eruption and their families have been awarded more than $10 million in total reparations for the fatal tours.

Earlier this year, Judge Evangelos Thomas sentenced five companies that took tourists to the volcanic island and said reparations were to be paid by the island's owner Whakaari Management Limited, White Island Tours and the helicopter company Volcanic Air Safaris.

Natalie Akoorie/RNZ