Subdividing land in the Taupō catchment

The regional plan has permitted activity rules for on-site wastewater systems and for animal grazing, that can have implications for area and nitrogen requirements for subdivided land.

• If a new property is to have a permitted activity on-site wastewater system, it must comply with Rule 3.10.6.3 for an advanced wastewater system or Rule 3.10.6.4 for a standard septic tank system.
• For a property to have a standard septic tank, it must be at least 4ha in size (as per Rule 3.10.6.4).
• Any property less than 4ha must have an advanced wastewater system (as per Rule 3.10.6.3).
• For the wastewater system to be permitted by Rule 3.10.6.3 or 3.10.6.4, Land Use Rule 3.10.5.1 must be satisfied.
• For Rule 3.10.5.1 to be satisfied either:
  • The property (or area to be subdivided) was used for farming activities (areas in pasture not including retired or forestry) as at 9 July 2005, and the land has not had a nitrogen allocation via land use consent, and the conditions of the rule are satisfied (including limitations on animal numbers), or
  • The property was used for farming activities as at 9 July 2005 and did have a nitrogen allocation via land use consent, or the land had a nitrogen allocation but was not used for farming activities, and a land use consent shows there is sufficient nitrogen allocated to the land "for farming" (12 kgN/ha/yr) and wastewater (3.5 kgN/yr for advanced systems or 10 kgN/yr for standard septic tanks).

As explained below, this means for a new 5000m2 property that was subdivided off a larger property that was not benchmarked but was in pasture as at 9 July 2005, no additional nitrogen would be required, and no accounting for nitrogen is required.

A minimum property size of 5000m2 is required to install an advanced wastewater system unless it was granted subdivision consent prior to 9 July 2005.

If the permitted activity wastewater conditions cannot be met, a discretionary activity consent could be applied for under regional plan rule 3.5.7.7.

To complete a subdivision down to 5000m2 on land that has a nitrogen allocation and was consented or not consented to farm under rule 3.10.5.3, to allow for an advanced wastewater system, accounting of nitrogen is required.

The Section 32 report for the Taupō Rules explains how the minimum property sizes were determined (see pages 153-155). It assumes that for a typical 5000m2 property, half the property is used for house, driveway, lawns and gardens, and half could be used for animal grazing.

Rule 3.10.5.1 requires that for a 5000m2 property, 2500m2 may be used for farming. If 12 kgN is needed for farming activities on 1ha, then 3 kgN is needed for 2500m2 (i.e. 1/4 ha).

So, to satisfy Rule 3.10.5.1 for a 5000m2 property, 3 kgN/yr is needed for potential farming, and 3.5 kgN for an advanced wastewater system. So, for a 5,000 m2 property that was farmed and had a nitrogen allocation and was consented or not consented under rule 3.10.5.3, a land use consent would be needed to show there is 6.5 kgN allocated to the property for the permitted animal numbers and wastewater nitrogen.

This can also be scaled up. For a 1ha property, we would assume again that 2500m2 is used for house, driveway, lawns and gardens, and the balance of 7500m2 (3/4 ha) may be used for farming and therefore needs 9kgN/yr (plus the 3.5 kgN for wastewater).

To complete a subdivision down to 5000m2 to allow for an advanced wastewater system on land that was used for farming activities (wholly pasture) to permitted activity levels, that does not have a nitrogen allocation, no accounting of nitrogen is required.

However, if any of the proposed lots include a portion of land that was NOT pasture as at 9 July 2005 (such as a forestry or retired area that was fenced off to exclude stock), accounting of nitrogen IS required.

Figures to use for the accounting of nitrogen

Rule 3.10.5.1 does not allow for covenants that state no animals will be grazed on the property. If such covenants are to be used to reduce nitrogen requirements in cases where the property being subdivided was used for farming activities under rule 3.10.5.3, because no permitted activity rules allow for this, a consent would be required for the wastewater discharge.

If additional nitrogen is required for a property or whole development, the nitrogen will need to be purchased from another landowner in the Taupō Catchment. A consent is required from Waikato Regional Council to transfer nitrogen between properties.

If a subdivision is to have reticulated sewage, no consents are needed for on-site wastewater, so wastewater Rules 3.10.6.3 and 3.10.6.4 do not apply. If the property sizes are less than 2500m2, we will generally assume that the whole property is used for the house, driveway, lawns and gardens and that land use Rule 3.10.5.1 is therefore not relevant. However, for larger section sizes, even if the property has reticulated sewage, Rule 3.10.5.1 requirements for nitrogen for farming must be satisfied.

If the land was benchmarked and has a nitrogen allocation greater than 12 kg N/ha, then the landowner could (prior to subdivision) reduce the nitrogen on the land for farming activities to 12 kg N/ha. Excess nitrogen could be sold to another Taupō Catchment landowner. This would need to occur through a consent process.