An environmental group says irrigation schemes won't necessarily protect farmers from a changing climate and may actually make some more vulnerable.
Forest & Bird advocacy manager Kevin Hackwell says irrigation will lead to an intensification of farming, with farmers running more stock and needing more inputs to farm.
He says the higher farmers are geared, the more likely they are to use up to the maximum of their water storage, and the more risk they face if irrigation fails.
He warns that if farmers build up infrastructure on the basis that water supply will always be reliable, their investment will be at risk if they get two droughts in a row - and theat is more likely with climate change.
"With water storage you've got to give yourself a really good buffer," he says.
Irrigation subsidies questioned
Mr Hackwell also questions why New Zealand taxpayers are contributing to the schemes, when he says the extra wealth generated by irrigation will be captured by a few.
"In a lot of cases these irrigation schemes, they're about private benefit. There'll be individual landowners who will benefit from getting the water (and) will be making the profits out of them."
He asked why irrigation schemes can't be funded by those who are going to benefit from them.
"If these are such good propositions, why do they need massive public subsidies?"
However, the Minister for Primary Industries Nathan Guy says the current drought illustrates the need for irrigation to store and distribute water.
He says if all the proposed major irrigation schemes around the country come to fruition, up to 400,000 hectares of farmland could be irrigated.
