An iwi opposed to the Ruataniwha dam says if the scheme proceeds it should be scaled back by a third and users charged a 5c per cubic metre levy to mitigate the environmental and cultural effects of the project.
In its 57-page submission to the board of inquiry assessing the Tukituki Catchment Proposal, Ngati Kahungunu Iwi Incorporated (NKII) sets out a number of reasons for its opposition to the Hawke's Bay Regional Council's Ruataniwha Water Storage Scheme.
Under the scheme, the council's commercial arm, Hawke's Bay Regional Investment Company, is proposing to build a $265 million dam on the Makaroro River, northwest of Waipawa and Waipukurau, with a 90 million cubic metre water storage capacity.
In its submission, NKII says a number of hui it has held have highlighted tangata whenua concerns about "inappropriate" management of water resources in the region which have lead to over-allocation, drying of streams and increased pollution.
"The [Tukituki Catchment] proposal promotes substantial increases in land use intensification without, in our view, sufficient measures to avoid, remedy or mitigate adverse effects from contaminants and nutrients on surface water and ground water," NKII's submission says.
The iwi says it has never relinquished its rights to and interests in water under the Treaty of Waitangi but did not have an adequate role in governing and managing the local water resource. Consultation on the proposal had been insufficient, the iwi says, and more sustainable alternatives had not been adequately considered.
"The location for the proposed dam and water storage area is on a major fault line and there has been a substantial increase in the number of medium-to-large earthquakes in Hawke's Bay over the last five years," the submission says. If the project were to go ahead the storage capacity of the dam should be restricted to 60 million cubic metres with the consequential reduction in the proposed 83m dam wall.
The iwi also wanted a 5c per cubic metre charge on all water used for irrigation under the scheme "such monies to be used for iwi/hapu cultural monitoring and kaitiakitanga [guardianship] purposes, including environmental mitigation and enhancement".
NKII has had its concerns about the need to mitigate potential environmental impacts heard by one of the council's commercial partners, South Island iwi Ngai Tahu, which has signed up as a potential investor in the water scheme. NKII chairman Ngahiwi Tomoana said over the weekend his iwi had reached agreement with Ngai Tahu that the South Island iwi would pull its investment in the scheme if the water storage proposal does not reach "the same high ecological and cultural standards" the iwi has for its own rivers.
The board of inquiry will begin hearing oral evidence from the project's backer and opponents when it begins sitting in Hastings on November 18.