Dairy farms in New Zealand use as much water as 60 million people, experts say.
According to a new analysis, New Zealand's dairy industry - which adds up to 2,000 farms - uses water equivalent to the combined populations of London, New York, Tokyo, Los Angeles, and Rio de Janeiro.
Officials are currently proposing a water tax on dairy farmers.
Agricultural economist Peter Fraser has commented on the issue, and proposed a water tax.
"There's an issue here with how we've gone and used our land. Why have we gone and put these incredibly water hungry uses such as dairy farming in such water scarce areas?" Fraser told New Zealand media outlet Stuff.
"It's because the water's free."
The analysis found that the average cost of a water tax on an irrigated dairy farm would be between $10,000 and $15,000.