Nitrate pollution in Canterbury water is getting worse - study

The state of New Zealand's water is back under the spotlight following the publication of new research on dairy farming.

It's found there is not enough rain and river water in Canterbury to dilute nitrate pollution into acceptable drinking water standards.

Water quality is an ongoing and growing issue in New Zealand.

"We're amongst the worst in the world in the way we treat our water," the study's author Dr Mike Joy said.

And particularly in Canterbury.

"Where three-quarters of the monitored groundwater sites are getting worse, significantly worse," Dr Joy said.

Now, a study suggests every litre of milk produced in the region needs up to 11,000 litres of water to dilute the pollution from its production and that's more than what is available.

"It's just been a hands-off approach to intensification of farming, there's been no enforcement by regional councils, very weak standards set by central government," Dr Joy said.

He said Environment Canterbury (ECan) has failed its region.

"No, I don't agree with that," ECan director of science Dr Tim Davie said.

Because ECan said it's been working hard to improve things.

"Fundamentally we're all saying the same thing, we need to improve the environmental footprint from farming, farmers know that, farmers are working on it," Dr Davie said.

"We know that, we're working on it, it is heading in the right direction, we're not there yet though."

"I really feel for the farmers because they're trapped by their own industry pushing them and a failure of government to limit them," Dr Joy said.

But farmers say dairy farmers aren't solely to blame.

"You just don't take the cows off the Canterbury plains and it's all going to go away," Federated Farmers board member Chris Allan said.

"The rivers don't care or the aquafers don't care where the nitrates come from, whether they come from cows, sheep or potatoes."

He said farmers are working hard and things will improve, it will just take time.

"Absolutely it can get better, we've got new technologies, precision agriculture, good management practices, farm environment plans. Give a farmer a problem and they solve it and that there's what we're doing," Allan said.

According to Allan, it's still good enough to drink.

"Tastes like water to me."