In an effort to get intensive farms legally consented, Horizons Regional Council is proposing to change numbers on the maximum nitrogen they can leach in its controversial One Plan table.

The matter was discussed at a strategy and policy committee meeting on August 14, and councillors agreed to a three-staged approach.

Last year the Environment Court told the council it must refuse consent to farmers unable to restrict nitrogen leaching to totals in the One Plan's Table 14.2. The totals were taken from a version of Overseer, a computer system for estimating the amount of nitrogen leaching through soil.

Read more: Editorial: Horizons need to be consistent in regulation


The figures were from a 2007 version of Overseer. It has been updated eight times since, and its estimates of nitrogen leached have increased 60 per cent.

Meanwhile, the council has been steadily checking nitrogen in waterways. It has found some decreases, and no increase anywhere near 60 per cent. Its conclusion is that the nitrogen unaccounted for is being lost as a gas.

Horizons Regional Council is taking a three-staged approach to intensive farming consents and their effect on water, chairman Bruce Gordon says. Photo / file
Horizons Regional Council is taking a three-staged approach to intensive farming consents and their effect on water, chairman Bruce Gordon says. Photo / file

About 90 per cent of region dairy farmers could not meet the Table 14.2 figures, Whanganui Horizons councillor David Cotton said. Yet the intention of the One Plan was to achieve better water quality - "within the means of most farms".

People who could not meet the maximums in the table were given 15 to 25-year consents, Palmerston North Horizons councillor Rachel Keedwell said. They were simply asked to reduce their leaching and use good management practices.

The Environment Court found this unlawful, and asked Horizons to stick with the existing maximums. Changing the numbers in the table, in a plan change notified by the end of this year, will make lawful consenting possible.

It could take two years to formally change the plan, and Overseer numbers could change again in that time. But Horizons staff have said further big jumps by Overseer are unlikely, and the changed numbers will allow more farms to comply.

Councillors were assured nitrogen making its way to rivers will not increase with the new numbers.

There could be equity issues though, because farmers who got the earlier consents had an easier time, Keedwell said.


And there will still be some farmers who cannot meet even the new maximums - horticulturists, for example, who can leach twice as much as intensive dairy farms.

The council plans to notify another plan change next year. It would give those farmers consent, provided they are on track for gradual reduction.

The next stage is a catchment by catchment overhaul of freshwater management, where residents will discuss and agree on water quality targets. It will take until 2025 to cover all seven catchments.

In Cotton's personal opinion, it will be the best long term answer.

"All the rivers have different problems. For the Whanganui, it's sediment, and it needs trees on the hills. For the Manawatū it's nitrogen. We have only got one law for all catchments," he said.

Keedwell isn't so sure a collaborative process will work. She said people in the collaborative Land and Water Forum failed to reach agreement, and environmental groups walked away.

Both councillors say the council is moving in the right direction, though Keedwell said progress has been slow and costly.

Fish & Game is one of the parties that took Horizons to the Environment Court over its previous consenting. Its CEO Martin Taylor said the Parliamentary Commissioner for the Environment is investigating the Overseer programme at the moment.

He didn't know what the committee had decided, but had little faith in the council.

"We are highly sceptical at this stage, if the plan changes make it easier for the people who are polluting to go on polluting. Perhaps instead of focusing on the vested interests of a few dairy farmers they should focus on the environmental health of their rivers and streams, which they have an obligation to do under the Resource Management Act."