Four key transmission lines cross the Rangitata River supplying the Upper South Island (USI) and HVDC circuit. The flooding of this river on 8 December 2019 led to 9 transmission towers on the Islington-Livingstone section of the line sustaining extensive damage. Due to the extended period of time that it is expected to take to permanently repair the line, information from the System Operator will be published on this page.
A temporary line was commissioned on 27th March 2020, which will provide an interim solution until the section is permanently repaired. On the 15th of April 2020 the temporary line was re-rated, increasing its operational capacity.
The Grid Owner scheduled outage dates for the recommissioning of the permanent line. This outage can be viewed on POCP.
Final update
28 August 2020
- The permanent line was returned to service on Friday 28 August.
- The reconductoring and recommissioning work for this outage was completed as planned.
- Transpower thanks our service providers, contractors and consultants for their work, and customers for their cooperation and collaboration during these outages.
The image below shows the area that is defined as Upper South Island (USI)
Industry briefings and presentations
Meeting minutes from the Customer conference call on 16/12/19 [ pdf 145.49 KB ].- Slide deck from the USI Operational Working Group teleconference call on 18/12/19 [ pdf 436.41 KB ]
- Meeting minutes from the Customer conference call on 20/12/19 [ pdf 138.65 KB ]
- Meeting minutes from the Customer conference call on 22/1/20 [ pdf 664.45 KB ]
- Meeting minutes from the Customer conference call on 3/7/20 [ pdf 88.37 KB ] (Recommissioning ISL-LIV permanent line)
Customer Advice Notices (CANs)
- CANs related to the Rangitata flooding event can be found here:
Links to Additional Information
- The outage can be viewed on POCP. Any changes to the outage will be communicated through POCP.
- Temporary ISL-LIV Transfer Limits Report [ pdf 768.91 KB ] (revised 14 Apr 2020)
- Upper South Island Load Data
- ISL-LIV Outage AVI-BEN Constraints [ pdf 394.88 KB ]
