Dairy and horticulture land use limited by nitrogen regimes

If involved in the purchase of dairy farms or land for horticulture you need to be aware of the potential for different nitrogen leaching regimes to apply around the country. These regimes apply in the Bay of Plenty (Rotorua Lakes), Canterbury, Manawatu-Wanganui, Otago and Waikato (Lake Taupo), and are soon to follow in the Auckland region. If advising on the purchase of land, there is a need to be certain as to whether the current or proposed rules restrict the intended use of land, whether rights can be traded, and whether any necessary resource consents for the intended land use are likely to be granted. Expect more regional councils to adopt nitrogen leaching regimes driven by the government’s anticipated freshwater reforms due in 2013.


The proposed unitary plan is expected to contain controls on nitrogen leaching when notified in 2013.

Bay of Plenty (Rotorua Lakes)

Rule 11 of the Bay of Plenty Regional Council’s Water and Land Plan targets the Rotorua Lake catchments (Lakes Rotorua, Rotoiti, Okareka, Rotoehu and Okaro). Nitrogen leaching is capped based on a historical benchmark. Activities complying with the cap are permitted. In most cases, the benchmark is an average of the annual nitrogen and phosphorus losses between mid-2001 and mid-2004. The Bay of Plenty Regional Council is considering implementing a trading regime.


Until 1 July 2017 the proposed Canterbury Land & Water Regional Plan requires all farms to record their nutrient loss using a computer programme and provide the record to the council on request in order to be a permitted activity. Farms within the Lake Zone must also prepare a farm environment plan for annual audit to be permitted. After 3 consecutive complying audits, the audits occur at three year intervals. After 1 July 2017 leaching limits will apply.


The One Plan for the Horizons (Manawatu-Wanganui) Regional Council is the first in the country to reduce the amount of nitrogen allowed to leach from properties into waterways from current levels. It requires farmers to meet decreasing nitrogen leaching limits over the next 20 years, using a software model to monitor nitrogen losses from the soil. All dairy, irrigated sheep and beef, cropping and vegetable farmers will require resource consent to discharge contaminants from their soil into lakes and rivers. Discharge limits vary according to land classification. The classification system takes account of soil type, geology, slope, vegetation cover and climate to give land a score from 1 (the flattest and most productive land) to 8 (steep, mountainous land). The One Plan sets higher leaching allowances for the best land, and lower limits for steeper country. The horticulture industry has challenged these rules by a High Court appeal, which is currently pending.


The Otago Regional Council has proposed Water Plan Change 6A (water quality) which aims to maintain good water quality. New controls will allow discharges that meet limits for nitrogen, phosphorus, E.coli, and sediment.

Waikato (Lake Taupo)

The Waikato Regional Council has rules (Variation 5) which aim to maintain the water quality of Lake Taupo at its current level by monitoring and capping nitrogen leaching. Variation 5 requires landowners in the Lake Taupo catchment to use of a software model to determine maximum annual nitrogen loss and a nitrogen management plan to show this limit will not be exceeded. Landowners/users are able to trade unused discharge rights under on a lease or sale basis. Activities that comply with discharge limits do not require resource consent.