Ngati Kahungunu wants to tell a government-appointed panel why it's opposing Hawke's Bay Regional Council's proposed Ruataniwha dam.
A board of inquiry has been brought in to examine the water storage project, submissions on which closed on 2 August.
The board bypasses the Environment Court process in the consideration of resource consents for what would be the biggest dam construction in 20 years.
Ngati Kahungunu Incorporation chairperson Ngahiwi Tomoana says his tribe did not have enough time to consider the council's proposal. He says it would have liked to examine the plan and look at areas such as the economical and environmental values of the scheme.
Mr Tomoana says the iwi has lodged a submission with the board of inquiry outlining its reasons for opposing the plan, and he hopes that will encourage the board to slow down and return to the consultation process, thus giving the iwi time to look at all of the relevant information.
Given more time, he says, Ngati Kahungunu might have supported the proposal.