33 kV Line Replacement Project



The Project

A rise in developments and subsequent load growth along with future hydro generation in South Westland were drivers for the replacement of the existing 33kV cct from Hokitika to Hari Hari.  This immense project was delivered to the client, Westpower, in two stages and covered a total distance of approximately 40.5kms. The replacement line operates at 33 kV but was designed to run at 6 6kV.

The project included preliminary investigations, design, material procurement and 33 kV line construction including a small component of 11 kV.


Key Dates

Commenced: 2008
Completed: 2011


This project showcases ElectroNet Services power to deliver excellence in terms of technical quality, service and safety through the expertise of the highly skilled multi-disciplinary design and build teams.  The Group worked collaboratively throughout this project to determine suitable technical solutions to challenges, such as; constructing among sand dunes and incorporating 11 kV distribution lines along certain sections.

This innovative approach by Electronet Services demonstrates a clear and shared vision with all other stakeholders and ensures the delivery of a successful, superior project.

The role of power is expanding and projects such as the HKK-HHI 33 kV Line Replacement highlights the ever increasing demand for experienced design and build teams to produce superlative conceptual designs resulting in successful builds of an extremely high standard.

Technical Complexity

To ascertain design parameters and address any constraints that could cause complications during the project a preliminary investigation was required and included; discussion with local authorities to address any consent issues, profile of the area, investigation of appropriate design parameters and investigation of any fault level issues that may arise.

A comprehensive, peer reviewed design report was produced consolidating the data from the preliminary investigation and ensured a secure, robust construction of the following in two stages:

Stage I – Waitaha Substation to Ross Substation

  • 66 kV design to operate at 33 kV
  • Aerial Earth from Waitaha and Ross Substations
  • 7.5km of underbuilt 11 kV on sidearms
  • Line primarily Delta Configuaration
  • Length of line approximately 15.5km

​Stage II – Ross Substation to Hokitika

  • 66 kV design to operate at 33 kV
  • Aerial Earth from Ross Substation
  • Designed in PLS CADD
  • Line primarily Delta Configuration
  • Constructed along existing line route
  • Designed to eliminate hazards of poles within a golf course by removing pole positions from tee off (Hokitika Golf Course)
  • Length of line approximately 25km ​


The strength of the Electronet Services design and build teams proved vital for clear, concise communication with all stakeholders and ensured suitable solutions were implemented for any potential issues that could arise during the project.  It was crucial to establish optimum pole positions during the construction process to alleviate any inconvenience to affected landowners.  This was achieved by continuously building feedback, from all interested parties, back into the project.

Electronet Services takes pride in its ability to deliver on quality service and is adept at coordinating and managing many stakeholders.

Establishing a collaborative project environment was key to the success of this project and enabled the design and build teams to actively implement real-time process changes to meet the needs of all stakeholders, resulting in a successful build.