"There is more work to be done before we get to that point," she said.
The Government has already given the project $1.25 million for future investigations and Greater Wellington has also committed money toward the research.
She said the Government's willingness to be an early investor in new irrigation schemes meant it recognised the economic benefits that could be provided by more reliable water.
The investment company will kick-start projects and help unlock massive opportunities for New Zealand, Mr Guy said.
The project would create jobs and security for farmers, said Masterton district councillor David Holmes, who is keen to see the project underway.
He said last week's downpour was a perfect example of what could be saved for a dry summer, if the irrigation was in place.
"The incentive is coming from central government which is wonderful."
However, with many other regions also proposing irrigation schemes, Wairarapa would have to "wait in the queue", he said.
Mr Guy said the crown company would be a minority investor in irrigation projects.
"Crown Irrigation will invest where it is considered necessary to get a project underway."
With a few billion dollars worth of investment, New Zealand could future-proof its agricultural sector and thus its economy, said IrrigationNZ CEO Andrew Curtis.
Mr Curtis said the financial support for irrigation infrastructure was long overdue.
"Many communities have been trying for several years to raise sufficient investment capital so our plea is for Irrigation Investments Ltd to move quickly to turn proposals into reality."
He said over a billion dollars was wiped out in the summer by drought and the country couldn't afford to bail out its agricultural industry twice every decade.
Mr Curtis says the answer lies with a combination of regional and on-farm water storage development.
Mr Guy said irrigation would help boost exports, creating thousands of jobs. Better river flows could also improve habitats for fish and birdlife.
