On Saturday, 22 November 2025, the NWIS experienced a major disturbance, causing widespread loss of supply across the East and West Pilbara covered networks.
A formal investigation was undertaken under Rule 197 of the Pilbara Networks Rules (PNR), with support from an independent consultant, to assess the incident and its impacts and identify measures to strengthen system security and reliability.
The investigation is now complete and the ISO has published its report, including the event timeline, a factual report prepared by the independent consultant, and any proposed changes to Rules, Procedures or operating practices identified by the ISO.
Information has been redacted where required to meet confidentiality obligations under the PNR.
The ISO invites stakeholders to make formal written submissions on the report. Submissions will be considered in progressing any proposed changes to Rules, Procedures or operating practices.
The indicative consultation process timeline is as follows:
| Event | Date |
|---|---|
| Consultation paper published | 20 May 2026 |
| Public submission period | 20 May 2026 – 25 June 2026 |
| ISO Rule / Procedure Change Proposals | Q3 2026 |
Submissions
Pilbara ISOCo is inviting stakeholders to provide feedback on the Investigation Report Blackout Incident on 22 November 2025 before 5pm on Thursday 25 June 2026.
All submissions received are taken into account in developing Rule and Procedure change proposals.
Submissions received will be published on this website. If a submission contains confidential information, you should notify the Pilbara ISOCo of this when making your submission. The submission must clearly identify the information that is the subject of the claim for confidentiality and you must also supply a non-confidential version of the submission.
Submissions must be received by the deadline. Please provide submissions electronically via our online form.
Documents related to this proposal
Investigation Report – Blackout Incident on 22 November 2025