The recent 7.8 magnitude quake and series of aftershocks that have so drastically impacted the communities of North Canterbury serve as a harsh reminder of the benefits of foresight when it comes to investing in our own infrastructure assets.
After six years of earthquake recovery and rebuild, the city is in good shape to withstand the impact of future seismic events. We live in a seismic environment. It is for this reason that we must continue to invest in the resilience of key infrastructure that allows us to get on with our lives, and growing a thriving and vibrant economy.
Our electricity network is one of those critical fundamentals. It is also a great example of where foresight prepared the city well for some of its darkest days. Power was restored to the majority of the city very quickly after the February 2011 quake because of decades of prudent smart planning, investment and timely maintenance.
Although systems performed well there are still lessons to be learned. Orion openly states that its principle objective following the earthquakes has been to restore resilience to the network and reliability of power supply to our wider Christchurch community by 2019. That involves several significant projects – the 66,000 volt ‘northern loop’ cable project is one, as well as improvements to the supply to Lyttelton and the surrounding bays.
In working towards this goal Orion has approached the recovery and rebuild of the city in a disciplined and collaborative way. It is working with business, industry and community groups to ensure that in future events the network is resilient and flexible. The ability to reroute electricity flow away from damaged circuits to other, undamaged, parts of the network is critical to keeping the network working.
The recently completed northern loop project was five years in the delivery and is one of Orion’s largest ever projects. It is effectively a super highway solely dedicated to the effective distribution of power around and across the city. This will have a major positive impact on protecting our communities and businesses. It will also provide a strong foundation to support new technologies such as solar, battery storage and electric vehicles.
Recently there has been concern about interruptions to the electricity supply to the Lyttelton area. Lyttelton and surrounding areas are vital parts of our community fabric, and the port is critical to the success of our local economy. Improving the surety of power supply to and in the Lyttelton area is therefore a priority. Orion has been working on this issue for some time, but it’s not a quick fix and the investment required is significant.
The power supply to this area comes from the Heathcote Valley substation via two overhead lines that that share a common set of poles. This is tough terrain and a harsh climatic environment so there’ll be risk of power outages from time to time.
The best and most cost-effective way to improve the reliability of power supply to Lyttelton is to run a separate cable through the Lyttelton tunnel, which would then provide an additional source of power. But this requires NZTA approval because it owns the tunnel.
I understand Orion has been in conversation with NZTA for some time now and an agreement is not too far away. In the meantime, Orion has invested more than $1.5 million as a first step to improving the resilience of the Lyttelton network. This includes significant work on substation relocation and renewal.
Preparatory work has set the Lyttelton network up to receive the planned cable through the tunnel. Once an access agreement is finalised, phase two of the Lyttelton Project will commence with the installation of the cable through the tunnel, which should be completed within 24 months.
Further work is underway and more is scheduled on the two existing overhead lines into Lyttelton to improve the reliability of power supply in the interim.