What New Zealand’s New Vegetation Management Regulation Means for Utilities

24 Jul

This year, electric utilities in New Zealand are preparing for regulatory updates that will expand their ability to manage trees planted by customers or growing outside their direct rights of way. While the changes are a win for risk-based vegetation management, they also raise new questions about how to manage expanded zones effectively and safeguard infrastructure reliability.

From static rules to strategic risk management

Until now, New Zealand utilities operated under the Electricity (Hazards from Trees) Regulations 2003, regulations centered on fixed buffer zones, reactive maintenance, and limitations on proactive hazard reduction.

But recent reviews by the Electricity Authority (EA) have pushed for an updated framework that allows for more oversight, enabling utilities to better protect electrical infrastructure from falling trees.

In both 2023 and 2025, cyclones brought down trees located outside the designated Growth Limit Zone (GLZ), leaving tens of thousands of customers without power. Because utilities weren’t authorized to trim those trees, they couldn’t prevent the outages. These events reinforced the need for updated policies—and broader operational latitude.

What’s changing

While the legislation has not yet passed, utilities are preparing themselves for operational changes, including:

Wider Growth Limit Zones (GLZs): Utilities will be able to assess vegetation risk up to 24 meters on either side of power lines—up from just 4 meters for high-voltage and just 1.5 meters for low-voltage lines.
Tighter tree planting restrictions: Landowners will no longer be able to plant new trees on non-forested land.
Risk-based maintenance: The EA supports a move away from fixed trim schedules toward dynamic cycles based on species growth rates, topography, and historical outage data.

What this means for utility operations

These changes represent a significant shift from reactive vegetation work to proactive, risk-based decision-making. Operations executives now have the opportunity to proactively mitigate risks to reliability and address vegetation based on the risk it poses both in and outside of the right of way.

To do this effectively, they’ll need tools that can assess risk at scale and deliver insights that drive efficient, defensible decisions.

Why vegetation intelligence is key

Around the world, utilities are turning to vegetation intelligence platforms like Overstory to make this transition smoother, faster, and more effective.

Using remote sensing tools paired with AI-driven analysis, Overstory maps vegetation risk across entire T&D networks. Unlike manual inspections or drones, satellite-based monitoring provides fast, consistent coverage and apples-to-apples risk assessment—no matter the location or terrain.

With Overstory, utilities can:

Identify clusters of high-risk vegetation using satellite and near-infrared imagery
Track the condition and health of trees over time
Generate defensible reporting for regulators and stakeholders
Tailor trim cycles to risk and budget, not outdated schedules
Monitor resilience and reliability improvements year over year

What to do now

Compliance with these new regulations will upend traditional approaches in New Zealand, and now is the time for utility executives to evaluate approaches and solutions that drive compliance. Start by asking:

Are you trimming by schedule or by risk?
How do you currently evaluate vegetation threats across your system?
Manual methods won’t cost-effectively scale to meet upcoming compliance requirements. What solution (or set of solutions) can enhance these efforts?
Define success metrics. What reliability, spend, or work efficiency metrics will impact your organization and customers most? How will you achieve them?
Don’t re-invent the wheel. How can you introduce tools that fit with existing workflows while also growing with your team’s maturity and comfort with new technology?

New Zealand’s regulatory evolution mirrors a global trend: a move toward smarter, risk-based vegetation management grounded in data. As utilities across the country prepare for this shift, now is the time to test proven tools, build internal alignment, and implement scalable approaches that deliver both compliance and value.

See how Overstory helps

Overstory’s grid resilience platform is already helping utilities around the world reduce outages, optimize spending, and improve resilience. Explore how our customers are seeing measurable results: