Adroit Tiltmeters Revolutionise Risk Assessment for Firstlight Network Transmission Towers
In the aftermath of Cyclone Gabrielle, which caused widespread landslides and ground instability across New Zealand, Firstlight Network faced a huge challenge: monitoring the stability of its 70-year old transmission tower network scattered across some of the country’s most rugged landscapes.
Traditionally site visits and a visual assessment were the only options - often involving frequent helicopter inspections or long drives that posed risks to staff. That’s when Richard Leckie, a Transmission Specialist at Firstlight Network, was introduced to Adroit tiltmeters - an IoT technology solution that has the potential to redefine how the company manages risk and maintains infrastructure resilience.
Adroit is an environmental monitoring company owned by Spark NZ that has introduced a wide range of IoT sensors and cloud-based applications that enable remote monitoring of infrastructure and environmental risk factors.
We were doing inspections by helicopter every month, and for some high-risk towers, it was even weekly or daily,” says Leckie. “Now, we can reduce those trips significantly because we have the data coming directly to us
Leckie could see the potential application of these devices, providing real-time data on ground and tower movement could replace guesswork with precise, actionable insights.
“I first heard about Adroit through Firstgas,” says Leckie. “They were looking at using Adroit tiltmeters to monitor gas lines around slips, and I thought, ‘Maybe these could work for our transmission towers too.’ So, I got some in for a trial and I’ve been pleased with the results,” he says.
Monitoring Movement in Real-Time
Following Cyclone Gabrielle (and the huge rain events that preceded it), Firstlight Network faced an urgent need to locate high-risk towers for remediation – but which towers needed attention most urgently?
“We couldn’t get around to all the towers at once,” says Leckie. “Now, with Adroit tiltmeters, we can remotely monitor the high-risk ones and not worry about them unless there’s actual movement.”
The Adroit tiltmeter works by measuring even the smallest shifts in a tower’s alignment. Data is sent from the device by satellite to the Adroit Cloud Platform where it is fed into an algorithm that calculates the implications of those shifts based on the height of the tower and its structural dynamics. “Towers actually move a bit during the day due to temperature changes and expansion,” Leckie explains. “But if we see a tower ‘walking’ consistently in one direction, it’s a sign of an issue,” he says.
Some towers can easily be seen to be moving, but subtler long-term changes might previously have gone unnoticed. Now, with the Adroit tiltmeters in place, Firstlight Network can catch these early warning signs and act before the situation becomes critical.
“We were doing inspections by helicopter every month, and for some high-risk towers, it was even weekly or daily,” says Leckie. “Now, we can reduce those trips significantly because we have the data coming directly to us.
“It’s not just about knowing the ground is unstable,” Leckie says. “It’s about understanding the broader risk to the tower and the network,” he says.
Establishing Benchmarks for Better Decision-Making
One of the most valuable features of the Adroit tiltmeters is their ability to establish historical benchmarks for each tower. “In the past, the only monitoring device we had was what I could see and compare to photos taken from a helicopter,” Leckie says.
“I would be looking at the cracks in the ground, and other things for clues, and that was just a visual record. Sometimes we measured towers and could see ‘that one's down 250 millimetres on the leg’ - that was easy.”
“But there was one that was down 70 mils, and then you find yourself asking: “Has it always been like that? Did it happen in the earthquake in 2009? Did it happen in Cyclone Bola?" These towers are 70 years old, so the Adroit sensor gives us a recent history. They just sit there, recording.
“At the moment I've got a tower that's moving about 20 mm a month and I just cannot see that."
“Now, with the tiltmeters providing a continuous record of each tower’s movement over time, the data allows Firstlight Network to identify patterns and prioritise mitigation work. We can now say: ‘this tower has been moving steadily, and this one hasn’t moved at all,’ Leckie says.
“It gives us an answer that we didn't have before. I still go to site, in the case of a big event that may trigger new slips close to towers, but we can look at the Adroit dashboard and go: “That's okay. Nothing's obvious yet, that's good.”
This capability has been crucial in adapting to a rapidly changing risk environment. “After Gabrielle, our top 30 at-risk towers completely changed,” Leckie says. “Some towers that were previously high-risk are now lower priority, while others have jumped to the top of the list. The Adroit technology helps us prioritise that maintenance.”
AI-Powered Insights for Proactive Risk Management
The system not only collects raw data but also processes it to provide meaningful insights. “The tiltmeters measure movement in fractions of a degree,” says Leckie. “But with the algorithm, we can translate that into real-world implications, like how much the top of the tower is shifting.”
This level of analysis has been particularly helpful in managing complex scenarios, such as towers located on fault lines or near high-risk areas like schools or urban centres. “Some towers are under more stress because of the way the lines pull on them,” Leckie explains. “The Adroit system helps us understand those forces and assess the risks more accurately.”
Looking ahead, Firstlight Network plans to have the Adroit dashboard on display in its control room, showing the continuous monitoring and tower movement in real time. “We also want to set up alarms, so that if a tower moves more than a certain amount, we’re immediately alerted.”
Leckie says the partnership with Adroit during the trial has been positive. “Adroit has been great to work with,” Leckie says. “They’ve been efficient in delivering the tiltmeters, helping us set them up, and providing the algorithm to manage and display the data. Their support has been great.”
As climate change and seismic activity continue to pose challenges for infrastructure management, technologies like Adroit’s tiltmeters are becoming indispensable. For Firstlight Network, they’ve not only reduced costs and improved safety but also provided a level of precision and reliability that was previously unattainable.
“This is about building resilience,” says Leckie. “Not just for our towers, but for the communities and customers that depend on them,” he says.