Rules introduced to protect fresh water against the impact of intensive farming are not being enforced by Horizons Regional Council.
Many farms are effectively operating without a consent and others have been granted consent to leach nitrogen at two or three times the One Plan limit at times throughout their 15-year consent period.
The One Plan, adopted by Horizons last year after a decade of planning, hearings and legal challenges, puts limits on nitrogen leaching by intensive farm operations, namely dairy farming, commercial horticulture, cropping and intensive sheep and beef farming.
Under the plan, existing intensive farming operations in targeted water management areas are required to apply for resource consent to discharge contaminants to the land and to water, and to have nutrient management plans to show how they will comply with the nitrogen limits.
The One Plan rules for some catchments, including parts of Wanganui and Rangitikei and also Lake Horowhenua and Mangatainoka, came into effect on July 1 this year.
However, figures released to the Chronicle this month reveal 80 per cent of farms in those catchments have not yet applied for a consent.
Of the 60 farms that have applied, none have been declined and so far 52 have been granted.
But 85 per cent of the 52 consents granted fail to meet the One Plan limits and have, instead, been issued with restricted discretionary consents, with some projected to have nitrogen leaching rates three times the limit.
The Resource Management Act requires consent applications to be publicly notified where the effects may be more than minor. None have been publicly notified.
Horizons strategy and regulations manager Nic Peet said he did not think the consents needed to be publicly notified as an individual farm would not have a more than minor effect on the environment.
"The effects are cumulative," he said.
The Act does define effect as including "any cumulative effect which arises over time or in combination with other effects".
On the missed deadlines, Dr Peet said July 1 was when the rules took legal effect but he would not expect everyone to have lodged an application by then.
"The key thing is that these steps are under way - that's the nature of new regulation," he said. "They won't have a consent but they are in the system on the way to getting one."
Horizons originally estimated 80 per cent of farms would meet the limit but now, in fact, 80 per cent of farms will not. That was why they were being issued discretionary consents, Dr Peet said.
The model used to measure nitrogen leaching did not provide an accurate measurement of what was getting into rivers, he said. "Effectively, the numbers act as a flag for us. The number on the table doesn't equate to outcomes in the river."
Horizons instead wants to look at it as big picture plan to reduce fresh water pollution. "That's more important than a single date on a plan," Dr Peet said.
A recent Massey University report on managing New Zealand freshwater biodiversity and supporting ecosystems said excessive nutrient run-off from over-intensive agriculture was one of several causes of pollution of the freshwater waterways.
-Another group of targeted water catchments in the region had a consent deadline of July 31, 2014, and the Chronicle has asked Horizons for compliance figures for those.