Industry lobby group DairyNZ was responding to staff advice circulated to Otago regional councillors as part of the deliberations over the council’s proposed land and water regional plan, due to be finalised in June next year.
DairyNZ general manager for sustainability Dr David Burger said it supported change on-farm where science highlighted the need for improvement.
"Good management practice gets all sectors moving in the right direction towards reducing contaminant loads, but DairyNZ also recognises further work may be required in some catchments, where good farming practices alone won’t achieve the desired water quality outcomes over the long-term," Dr Burger said.
However, he said there was already "a strong mechanism in place to manage further intensification", referring to the government’s national policy statement (NPS) for freshwater management.
"DairyNZ accepts Te Mana O Te Wai as the fundamental concept that sits at the heart of the NPS," Dr Burger said.
The regional council staff report identifies Otago as the third-worst region for increasing nitrogen loads and dairying in New Zealand after Canterbury and Southland, and suggests initiatives such as banning new dairy conversions or reducing stocking rates in certain under-pressure areas in order to ensure the water quality requirements are met.
Areas identified as not possible to clean up without this action include the Catlins, lower Clutha, lower Taieri and North Otago.
Forest & Bird freshwater advocate Tom Kay said DairyNZ’s comments indicated there was a growing realisation that "farm management plans were not enough".
"The writing has been on the wall for some time," he said.
In order to address water quality issues, regional councils needed to step up.
"Unfortunately, no matter how many farm plans we write, or how much ‘good management practice’ we have on our farms, it will never offset simply having too many cows in a catchment," he said.
"We have to have some very frank conversations about the places where we’ve intensified farming too much — and figure out how we can help everyone change to ensure our rivers and lakes are healthy."
Otago Fish & Game environmental officer Nigel Paragreen said Otago’s water plan had contained a "maintain and improve" style of direction for many years.
"I don’t think that has been effective in stopping water quality from deteriorating," he said.
The NPS for freshwater "requires us to draw a line in the sand about the quality of environment that we want to achieve".
"Its success will depend on a robust pathway to achieve it.
"We shouldn’t leave it to chance," Mr Paragreen said.
"This is a problem for everyone, not just one industry.
"The fundamental issue with balance is that it’s out of whack — our rivers, lakes and wetlands in some places are under stress."
Federated Farmers Otago president Luke Kane said the organisation could not comment in any detail on the report to regional councillors on nutrient stress on waterways, as it had not been made publicly available.
However, he said "at an educated guess there are now more than 20 active watercare/catchment groups in Otago and North Otago, with farmers and other landowners joining with others in the community to drive continued progress on waterway quality".
"Farmers are very aware of tougher environmental standards in place, and ahead of us," Mr Kane said.
"The vast majority are already utilising technology and good management practice — such as variable rate and precision fertiliser placement, timing of fertiliser application, proof of placement and monitoring of impacts."
New Zealand First candidate and former Federated Farmers Otago president Mark Patterson said the suggestions were likely to be controversial with farmers.
"Dairy farmers have moved a long way in recent times, and they’re continuing to build on the good work," Mr Patterson said.
"But the changes won’t happen overnight, and there’s going to be a lag effect."
