By working together, Ngati Kahungunu and other iwi hope to send a strong message about the state of Hawke's Bay's waterways.
Today Ngati Kahungunu will be presenting evidence to the Waitangi Tribunal at Waiwhetu Marae in Wellington, as part of stage two of the National Freshwater and Geothermal Resource Inquiry.
Hearings for the first stage of the inquiry were held in July 2012.
Ngati Kahungunu chief executive Adele Whyte said it was an honour to submit evidence on the first day for stage two - more than 800 pages worth - alongside the testimony and evidence from other Ngati Kahungunu whanau and Taiao (environmental) advocates.
"We're just all resolute that our waterways are really important, and that we want to protect them and we want to be seen to be doing all that we can," she said. "Giving evidence is another way for us to show how serious we are of protecting our waterways."