Media update regarding Grid Emergency August 17

18 August 2021

What occurred on August 17?

One of the High Voltage Direct Current (HVDC) conductors (wire) fell across State Highway 7 in the Weka Pass area, Waikari in North Canterbury. No one was harmed.

What is the latest?

Last night the road was cleared and reopened with the fallen conductor elevated above the road via hurdles.

On site assessments last night and today have revealed six towers which normally hold the conductor have been damaged as part of the failure.

Repair of the conductor:

We have crews on site now and work is well underway to plan the repairs.

Replacement equipment and conductor has been dispatched for delivery to site. The safety of our people is of the upmost priority particularly now we are operating under COVID-19 Alert Level 4 protocols.  

The terrain, ground conditions, and current and forecast weather is making the work challenging.

We have informed the market that we do not expect to have this conductor back in service before Sunday 22 August at 4:00pm.

What is being done to manage the supply of electricity while repairs are undertaken?

Demand is currently down around 15% and we expect this trend to continue while in Alert Level 4 lockdown.

We are in regular communication with industry regarding the situation, how demand is looking and what our level of supply is.

We are currently forecasting sufficient supply to meet demand this evening and out for the rest of the week, barring a major plant failure.  

Why did the conductor fall?

Our primary focus is to repair the issue. The investigation into why the conductor fell, will take time to complete.

Early indications are that this was a one-off fault and not a systemic issue.

What was Transpower’s response to the event?

We issued a Grid Emergency asking for increased generation and for electricity distribution businesses (lines companies) in the North Island to reduce all controllable demand (such as hot water).

The industry responded accordingly and Transpower was able to maintain the stability of the system nationwide without any disconnections. 


For further information, please contact:
Deborah Gray, Corporate Communications Manager, 021 624 170.