Farmers looking to buy water from the Ruataniwha water storage scheme will have a better idea of the costs when a contractor is selected to build the $230 million project by October.
Hawke's Bay Regional Council's investment company has shortlisted two companies which will now work on competing design and construction plans for the scheme, with the detailed costing expected by September.
It will provide farmers with an accurate price for access to water and critically, more information on the overall viability of the project in Central Hawke's Bay.
The first company shortlisted was France-based contractor Bouygues Construction which operated globally on large infrastructure projects, including dams and has a subsidiary based in Australia. The company will partner with the Napier branch of Opus International Consultants and MWH, recognised for their strong dam and irrigation design work around New Zealand.
The second was a joint venture between a Spanish infrastructure company Obrascon Huarte Lain, and New Zealand company Hawkins..
Obrascon Huarte Lain is ranked 21st among the 225 largest international contractors.
Hawkins is one of New Zealand's largest privately-owned construction companies.
Its dam design team is led by GHD, an Australian-based consultancy.
Water Infrastructure Group NZ would be involved in the irrigation distribution area, while GHD would cover the design of structures and canals.
Investment company chairman Andy Pearce said there were five companies from throughout the world who tendered for building the water storage scheme.
"We set up an expert selection panel which looked at everything from the companies' past experience in large infrastructure and dam building to their financial capability and ability to be innovative."
All five companies were of an extremely high standard and capable of delivering the scheme," Dr Pearce said.
"The two companies we chose exceeded the selection panel's expectations around understanding what is required through the design of the scheme and providing innovation for the dam and the distribution system."
Dr Pearce said the investment company accepted it was likely international expertise would be required to build the dam, given its size, scale and technical requirements.
Both companies will now be involved in a competitive final design phase which concludes in August.
A decision will then be made to select one of the two companies to build the project, should the scheme gain resource consent and proceed.
"This is a major milestone for the scheme because once we have detailed costings we will be in a better position to give farmers a more accurate idea of the price of accessing the water from the scheme."