Horizons' One Plan

November 2012


On 6 September 2012 the Environment Court released its decision on the Horizons Regional Council’s One Plan, which covers a substantial part of the central and southern North Island. The One Plan seeks to address four key region wide issues: declining water quality; increasing demand for water; sustainable hill country land use; and threatened native habitats.

One of the key issues considered by the Court was the effect of activities on surface water quality and, in particular, non point source nutrient discharges from agricultural activities. It is a significant decision that highlights the increased pressure being placed on the agricultural sector to reduce and manage nutrient discharges that affect water quality. 

What did the Environment Court say?

The central issue affecting surface water quality was the amount and types of run-off and leachates arising from agricultural activities that find their way into water bodies, namely rivers and lakes in the region. Much of the Court’s attention was focussed on nitrogen leaching, as it is particularly difficult to prevent it from getting into water, due to its ease of passage into water bodies through groundwater and also across the surface of land.[1]    

The Environment Court was critical of parties who submitted that there was no need to enhance water quality of some water bodies, as they were no worse than similar water elsewhere in the country. The Court held that such a proposition was in conflict with the purpose of the RMA, which among other things aims to sustain the potential of natural resources and safeguard the life-supporting capacity of water.[2]

In addition, the Court found that suggestions the science relating to nutrient discharges was insufficiently understood did not hold sway. The Court responded by saying that, whilst the science will never be fully understood, it is understood that the quality of many of the region’s water resources are degraded to the point of not being potable for human or stock, and that science does know how to stop it, and reverse it.[3]

The Court also noted that whilst voluntary programmes such as the Clean Streams Accord are a positive step, a regulatory regime of measurable standards was required to ensure compliance.

The decision reflects the view that agricultural activities are no longer “off limits”, and that any land use activity will be expected to comply with water quality standards, regardless of the activity. 

So what happens now?

Currently Horizons Regional Council is redrafting the provisions of the One Plan in line with the decision of the Environment Court. As such, the precise details of the One Plan provisions are not certain.

Within the region’s catchments a number of “priority catchments” have been identified.  Within these priority catchments existing dairy, intensive sheep and beef (which are farms that are irrigated and over 4 hectares), and cropping and horticulture operations will require a resource consent in relation to nutrient management.

In addition, any conversions to dairy, intensive sheep and beef, cropping and horticulture anywhere in the region will require resource consent for nutrient management. Nitrogen limits will be calculated based on land use capability (LUC), which is closely linked to soil type.

Federated Farmers and Horticulture NZ have lodged an appeal challenging the Environment Court’s rulings, including those related to the water chapters of the Plan and, in particular, the need for resource consents for intensive farming activities.  There is a general feel amongst both farmers and horticulturists that the One Plan will introduce significantly high compliance costs, meaning these activities will not be economically viable. Fertiliser Company Ravensdown has also joined the appeal.

Federated Farmers (among others) have been highly critical of the science used to measure and calculate nutrient discharges from farms and, in particular, use of the Overseer model. Originally designed to assess fertiliser requirements and nutrient flows around farm systems, Overseer is now in its 6th version, and being utilised in a much broader way.

In addition to a wider range of farm types and systems, Overseer is now being used by many regional councils (including Horizons) as the primary tool for calculating nutrient runoff. However, there are many variables that affect the amount of nitrogen a farm system leaches and, depending on the adequacy of the information being inputted, Overseer can give differences in leaching losses of ±20%.[4] 

This level of potential inaccuracy could represent issues going forward, especially in terms of enforcement of nutrient limits. If a farmer is prosecuted for exceeding nutrient allowances, it could be difficult to prove given the significant variability seen in Overseer results.

What will the decision mean in practice?

The One Plan reflects the move towards catchment-based water management that seeks to manage the effects of all land uses and activities within that catchment. The One Plan has already been a source of guidance for other regional councils around New Zealand. This can already been seen in other regional plans, such as the Canterbury Land and Water Regional Plan, which also seeks to manage nutrient discharges from agricultural activities by setting nutrient discharge limits.

The One Plan recognises the significant impact that nutrient discharges from agricultural activities can have on water quality and the growing scepticism that voluntary measures to mitigate nutrient discharges, whilst well intended, will not significantly reduce nutrient discharges without having measurable and enforceable standards in a regional plan.

However, whilst councils will have enforceable standards, the ease of enforcing those standards could be very difficult, given the potential for variability in results from the Overseer model. This has the potential to result in litigation, a result regional councils are seeking to avoid.

There is no doubt that compliance with the One Plan will increase the costs of agricultural activities for some operators in the region. However, many argue that this is no different from other businesses that discharge contaminants and require resource consents to do so, and is therefore just another cost of doing business.

We now await the High Court decision to see if the approach of the Environment Court is upheld.

[1] One Plan Decision Version: Part 5- Surface water quality- non-point source discharges [5-2].

[2] Ibid, at[5-7].

[3] Ibid, at[5-9].

[4] One Plan S42A Report- “Concerning Water Quality”, Dr Stewart Ledgard, at p4. 




Disclaimer: This is a brief sumamry for information purposes only and is not legal advice.

Posted on Wednesday 7th November, 2012 at 03:29 pm