The Hawke's Bay Regional Council will decide on 31 October whether to take a large scale water storage project to the next stage, by seeking resource consents.
A feasibility study presented to the council on Wednesday shows the Ruataniwha Project would be financially, technically and environmentally feasible.
After three years of investigation, planners are proposing a single large dam on the Makaroro River, rather than a series of smaller dams, to provide irrigation water for 20,000 to 30,000 hectares of farm land, on the Ruataniwha Plain in central Hawke's Bay. It will also provide limited power generation.
Council chief executive Andrew Newman says about 5000 to 6000 hectares in the area are irrigated. But he says even on that limited scale, irrigation is not sustainable in the long term without storage.
Mr Newman says it is the council's view is that current irrigation that is sourced from surface and ground water is having an adverse impact on river flows during summer months.
He says long term, there needs to be some sort of storage solution even if irrigation remains at current levels.
Mr Newman says if the regional council agrees to apply for a consent at the end of October, getting the Ruataniwha project to the construction stage is still a long way off.
He says there is a long way to go before the consent process is complete and assuming the project does get consent then investors still need to be willing to invest in it and build it.