New Zealand has about 720,000ha of land under irrigation, but about half that again could be sustainably irrigated by 2025, an industry body says.
IrrigationNZ's first annual "snapshot" showed that Canterbury - already the most irrigated province with 444,777ha under irrigation - had most of the potential, with a further 200,000ha on the drawing board.
The Wellington region, which has 16,638ha under irrigation, had 30,000ha more in the pipeline, the snapshot shows.
IrrigationNZ chief executive Andrew Curtis said about 350,000ha throughout the country could be sustainably irrigated by 2025.
New Zealand abstracts about around 2 per cent of its water resource - or 5 per cent if hydropower is excluded - which is low by international standards.
Irrigation accounts for 60 per cent of water usage and pastoral-based activities make up about three quarters of New Zealand's irrigated area - dairy 50 per cent and sheep and beef finishing farms 25 per cent.
The other 25 per cent of land under irrigation supports mainly vegetable and arable crops, alongside fruit and wine growing.
In 2012 it was estimated that irrigated farms provided a $2.7 billion contribution to the economy, and more than double this in terms of the benefits to the wider community.
Curtis said irrigated agriculture underpinned several of the provincial economies on the east coast of New Zealand.
IrrigationNZ chairwoman Nicky Hyslop said there had been a big increase in investment in upgrading irrigation systems, which had seen efficiency improve by 50 per cent over a generation.
Irrigation NZ represents 3600 irrigators and 150 service providers.
See the latest Irrigation NZ report here: