Accessibility. Skip to main content.

How the National Environmental Standards deal with electricity transmission activities (5 of 12)

These pages set out aspects of the NES that Transpower and councils need to consider for transmission activities.

  1. Summary of the NES
  2. Operation of existing transmission line and use of access tracks
  3. Overhead conductors and adding overhead circuits
  4. Earthwires and telecommunications cables
  5. Work on underground conductors / Taking existing overhead transmission lines underground
  6. Increasing voltage or current rating / Electric and magnetic fields
  7. Transmission line support structures — alteration, relocation, and replacement / Temporary / Removal
  8. Telecommunications and signs / Devices / Signs
  9. Discharges
  10. Trimming, felling, and removing trees and vegetation
  11. Earthworks
  12. Noise and vibration from construction activity

Work on underground conductors

Explanation: replacing and maintaining underground conductors

Replacing and maintaining underground conductors has no specific impacts, and is permitted without conditions – regulation 11(2) and (3). 

Explanation: adding underground conductors

Adding underground conductors (including adding circuits) is permitted - regulation 11(1) - provided that the EMF conditions in regulation 10 are met (Explanation: EMF conditions).

Taking existing overhead transmission lines underground

‘Undergrounding’, or moving overhead transmission lines underground reduces visual impacts.   For technical information on undergrounding see the Undergrounding section.

Explanation: undergrounding transmission lines

Placing an overhead line underground ('undergrounding') is a controlled activity – regulation 12 - provided it meets the EMF conditions in regulation 10 to be treated as .

Undergrounding a transmission line requires a termination structure (see technical explanation) at the point where the lines go underground. The definition of 'undergrounding' includes  altering, relocating or replacing an existing tower or pole with a termination structure. This could be required at one or both ends of the underground transmission line.

Explanation: conditions that apply to termination structures

The conditions relating to altering, relocating and replacing support structures set out in regulation 14 also apply to termination structures, for example:

  • If the replacement or relocated tower or pole is within 12 metres of an occupied building, or closer to the building (if the existing tower is already within 12 metres of the building), it is restricted discretionary - regulation 14(4).
  • If a pole is replaced with a tower, it is restricted discretionary - regulation 14(7).
  • If the height is increased by more than 15%, it is restricted discretionary - regulation 14(3).

The council can consider the following matters in relation to undergrounding transmission lines as a controlled activity - the location of the termination structure and the route of underground cables; earthworks and sediment; construction and effects on services and infrastructure.

Associated activites that may need consent

If work on underground conductors requires earthworks, then the earthworks regulations 33 apply. If vegetation must be disturbed to undertake the work, then the regulations concerning vegetation apply - regulation 33. Noise from construction activity may also apply (regulation 37).

If the voltage or current is increased for an existing underground line, then the EMF regulations apply - regulation 10.

View the transmission activity projects for other consents that may be required.

 

|

Last updated: 18 January 2010