Lake Rotorua

Lake Rotorua

Potential Impacts of Proposed Rules

The nitrogen reductions needed are large and challenging. This reduction is additional to work already done in the catchment by farmers, such as fencing off streams and planting trees.

We recognise the proposed rules will require more than farmers simply achieving good or best practice. The proposed rules will require system changes, or in some cases land use changes, throughout the whole catchment.

The proposed rules will have direct and indirect costs.  Farmers will have substantial costs which include on-farm changes and potential loss of farm value.  Beyond the farm gate indirect costs to industries such as suppliers, manufacturers, processors and contractors may occur.

An assessment was carried out for the Regional Council by Perrin Ag Consultants Ltd to help farmers understand what the proposed rules mean at an individual property level and the potential impacts on farm profits.


Report title 




On-farm effects of diverse allocation mechanisms in the Lake Rotorua catchment


Oliver Parsons, Graeme Doole and Alvaro Romera

Using representative farms from the Lake Rotorua catchment, this analysis estimates the profitability, productivity and land use change impacts of alternative nitrogen allocation methods on pastoral farming in the catchment. 

Appendices 1-4 - Input information

Appendix 5 - farm model method

Appendix 6 - optimisation model


Economic impacts of Rotorua nitrogen reduction. District, regional and national evaluation

Market Economics Limited

Based on the on-farm effects of alternative allocation methods (Parsons et al. 2015), this analysis estimates the impact of the proposed rules and incentives on the district, regional and national economies. 


Land values in the Rotorua area and Lake Rotorua catchment

Martyn Craven, Telfer Young (Rotorua) Limited

Using sales data and expert judgement, Telfer Young estimate the average size of changes in the property values resulting from the proposed nitrogen rules.  Drystock, dairy and lifestyle property values assessed. 


Rotorua NDA Impact Analysis D J Perrin, T Laan, L Matheson, D Walker Perrin Ag Consultants report on impact of Nitrogen Discharge Allowances on individual properties 2014