Land use change in parts of Canterbury looks set to be, at best, heavily regulated and, at worst, stopped altogether, if proposals in the Canterbury Land and Water Regional Plan proceed.
In the plan, Environment Canterbury has attempted to control what they perceive as the immediate risk of further water quality degradation caused by nutrient discharges from land.
The plan requires resource consent for land-use change, by using a definition of land-use change in combination with the 'nutrient allocation' status of the zone to determine how difficult it will be for farmers to get consent.
Land-use change is defined as "a resource consent to use, or increase the volume of, water for irrigation on a property" or "an increase by more than 10 per cent in the loss of nitrogen (N) from land used for a farming activity ...".
This percentage change in loss will be estimated using the Overseer nutrient model and compared with a baseline period between July 1, 2011 and June 30, 2013.
There are several flaws in this approach:
The margin of error in Overseer is around 20-30 per cent.
A 10 per cent change captures farms' routine yearly variation.
The time periods for estimating N loss are insufficient to span the cyclical farming operations, such as crop rotations.
Focus is on N loss, but this may not be a priority for a land use or a major concern in the determining the water quality of a particular catchment.
An increase in the volume of water for irrigation will also increase reliability of supply. Greater reliability will enable farms to increase plants' root zone activity - reducing overall nutrient loss.
The plan is currently going through its hearing stage and the definition of land-use change is undergoing vigorous debate.
Alternatives include using a greater percentage change, an increase in the absolute value for estimated N loss, or a combination of both; or moving to a production-based trigger, such as increases in stocking rate or change in yields in arable or horticultural crops.
A further option may include applying the definition only to activities currently requiring consents, such as water take and use or dairy conversions.
For the plan to function in its current state, it will be important to ensure a workable and fair definition of land-use change. Incentives must be right for farmers to make good decisions around nutrient management ahead of the catchment based discussions.
Federated Farmers considers it is more useful to focus on ensuring the plan encourages the adoption of on-farm Good Management Practice.
This approach, applied via Farm Environmental Plans in catchments where these are required, would have a broad water quality focus, rather than a narrow focus on one nutrient. This approach moves the conversation from land use change to sustainable land management.