Overseer is a tool used by Horizons and other regional councils to model nutrient losses for the purposes of planning, consenting and auditing.

On 11 August, central government released its report entitled “The Government response to the findings of the Overseer peer review report”. This report was Government’s response to the questions raised by the Parliamentary Commissioner for the Environment. As part of producing its report, Government commissioned advice from a panel of experts.
In summary, the expert panel concluded that in its current form, it would not have confidence that Overseer estimates of nitrogen lost from farms are suitable for use as a stand-alone measure of total nitrogen losses, that it does not have confidence that Overseer’s modelled outputs tell us whether changes in the farm management reduce or increase the losses of nutrients, or what the magnitude or error of these losses might be.

In response, Government has committed to continued support for Overseer. It has also identified a number of options for the future, including a second generation Overseer and new and alternative tools for managing nitrogen loss.

More detail can be found on MfE’s website.

What this means for Horizons Regional Council

Nitrogen discharge numbers are an integral part of the regulatory approach in catchments where a nitrogen reduction is needed.

In common with a number of councils, Overseer numbers are embedded in the One Plan and in resource consents in the region - particularly for intensive land use.

Overseer has been a useful tool to promote farm practice improvement.

Government has committed to improving Overseer and/or developing additional tools to be able to manage nitrogen loss. Horizons sees the urgent need for this to occur to support both water quality improvement and remove uncertainty for rural consent holders.

MfE will be providing council guidelines on how we can proceed, which will be important as Overseer has been the only tool available to us for modelling nutrient loss.

It is going to take some time to work through the implications of the report from Government.

Horizons will continue to administer its regional plan – the One Plan.

What this means for existing consent holders

Horizons appreciates that the Government report has caused concern for farmers with intensive land use consents.

The type of practice improvements farmers have been using to reduce nitrogen loss are backed by strong science. It is vitally important that these practices continue. Consents remain a legal requirement and you should continue to implement on-farm practices that reduce nitrogen loss in accordance with your consent and nutrient management plan.

Council has considered the implications for consent holders that are currently required to provide an annual nutrient budget as part of their Intensive Land Use (ILU) resource consents. In these situations, nutrient budgets are used as a sole measure to determine whether a farm is complying with its nutrient leaching limits.
Following the Government report, it is Council’s view that it would be unreasonable to require farmers to provide an annual nutrient budget as required by a condition of consent, given the budget cannot be used for a regulatory or compliance purpose.
Council will, however, focus its compliance efforts on whether the mitigations that have been committed to via the consent process and management plans have/are being implemented within the required timeframes.
Farmers are still encouraged to keep records of the data and information they have previously used to input into the Overseer model. The reasons for this are two-fold; firstly, maintaining these records may be a condition of an ILU consent and Council may wish to audit these records to check whether inputs on the farm are consistent with what was anticipated as part of the consent application process, and, secondly, this information will be critical for farmers as a new regional plan for freshwater is developed by 2024.
Council cautions against intensification occurring as a result of this issue. Intensification will require resource consent under the National Environmental Standard for Freshwater and is likely to result in non-compliance with existing ILU Consents.
As noted, your ILU consent remains a legal document. The mitigation practices you have committed to remain backed by strong science and implementing then is helping to improve water quality.

Plan Change 2

Plan Change 2 (PC2) looks to provide consenting pathways for intensive land uses subject to environmental improvements.

Overseer is currently a fundamental component of PC2.

PC2 also recognises practice change on farm and supports good and best practice, as well as the use of alternative modelling methods.

PC2 is currently subject to appeals before the Environment Court. Horizons will need to advise the Court of the Government report on Overseer as part of the appeals process and work through the issues that it raises.

As options become clearer Horizons will provide as much information as possible to affected parties.

Horizons is also seeking meetings with Government on the implications of its report for PC2.

Horizons is working with other regional councils that have Plan changes that use Overseer currently underway.

Essential Freshwater (NPS-FM and NES-F)

Horizons is currently in the process of preparing for a revised One Plan to give effect to the National Policy Statement for Freshwater Management (2020).

Regulation/use of farm plans to reduce nutrient losses from farms will be an important part of the Plan.

At this point Overseer is not able to be included as a regulatory tool based on Government’s report.

Government is of the view that a tool will be available by 2024 to help manage nutrient losses.