Mr Rangi says for this Rugby World Cup, the government asked Ngati Tuwharetoa and other iwi around the country to welcome the visiting teams.
"Ngati Tuwharetoa decided what better place to hold it than in a place that's very, very important to Ngati Tuwharetoa and in particular, Ngati Hikairo [the kaitiaki of Opotaka], and at a place that the South Africans will find very important because they've faced this haka for generations," Mr Rangi said.
"This is about sharing the story, Ngati Tuwharetoa's story around our version of the haka."
Planning for the powhiri has been going on for months, Mr Rangi said.
"There's been a lot of work put in by many people, especially the local hapu in that area and of course the tribe as well, to try and bring it to a state where we'll feel quite proud to welcome our visitors, but also being mindful that it's going to go across to the rest of the world.
"So we want to make sure that this cultural taonga or cultural knowledge that we have relating to this specific area, that we have the opportunity to tell its story but also to let people know that the hapu and the iwi are very proud that they're able to do this."
Opotaka offers spectacular views across Lake Rotoaira to Mt Tongariro and of course organisers were hoping for a fine day, Mr Rangi said.
However they had taken the precaution of constructing a temporary paepae for tangata whenua and manuhiri to shelter under if the weather was wet.
The powhiri will follow the usual format with a challenge issued to the visitors before they are brought up to the site, where Ngati Tuwharetoa and Ngati Toa tangata whenua will hold the powhiri.
Once the formalities are completed, local children will lead the visitors back down the path to a marquee for afternoon tea and entertainment by kapa haka groups.
The powhiri is expected to be about 60 to 90 minutes' duration as the South Africans will need to get back to their Taupo accommodation to continue their preparations for their World Cup matches, Mr Rangi said.
"But it will be long enough for the powhiri, I'm sure, to have an impact on them and certainly understand the haka the next time they face the All Blacks.
"When Ka Mate is done, they'll know a little bit more about where the haka originated."
Because the Opotaka site is relatively small and there is little carparking, the occasion is limited to invited guests only, including the South Africans, their management and families, marae representatives and kaumatua, who will be transported from Turangi by bus. A large media contingent is also expected.
However Turangi locals will be able to make a day of it in the Turangi town centre where they can listen to local musician Aaron Moeke, browse the stalls and shops, join in activities and games and then catch the ceremony being broadcast live on a big screen being set up at the west (library) end of the town centre.
The town centre celebrations will run from 11.30am until 2.30pm.
Opotaka - the site of the Ka Mate haka
It is said that Ngati Toa warrior chief Te Rauparaha composed Ka Mate after being pursued by his enemies to Opotaka, where he was hidden in a kumara pit by local chief Te Wharerangi.
His wife, Te Rangikoaea sat over the entrance to the pit.
When Te Rauparaha heard the pursuing warriors approaching he muttered "ka mate, ka mate (I die, I die)".
Then as he heard their footsteps growing fainter, he exulted "ka ora, ka ora (I live, I live)" before ascending out of the pit and into the sunlight ("Whiti te ra!"), where he performed his new haka.
Source: haka.co.nz.
