Facing relentless tropical weather and rugged terrain, Kauai Island Utility Cooperative (KIUC) rethought how it inspects its network of wooden utility poles. By adopting advanced non-destructive testing (NDT) technology, the cooperative streamlined operations, reduced environmental risk, and strengthened grid resilience without compromising safety or data integrity.
Pole Management on the Garden Isle
Kauai, often celebrated for its lush landscapes and coastal beauty, presents a very different picture to utility asset managers. Its year-round tropical climate and mountainous topography make utility pole inspection anything but routine.
For KIUC, the island’s sole electric cooperative, managing thousands of wooden poles meant battling persistent moisture, salt-laden air, and remote access issues. Until recently, KIUC relied on invasive inspection methodsthat were time-consuming and potentially counterproductive.
“Drilling was intended to assess condition, but ironically, it introduced new risks,” said John Cox, KIUC’s Transmission and Distribution manager. “Moisture intrusion at drill sites often led to accelerated decay.”
Compounding the issue was Kauai’s environmental exposure. Airborne chlorides, blown inland from the ocean, corrode not just metal components but wood as well, even miles from the shore. Combined with frequent rainfall and dense vegetation, it created a near-constant assault on infrastructure integrity.
With increasing concerns around wildfire mitigation and infrastructure resiliency, KIUC evaluated alternatives to legacy inspection methods. KUIC turned to a a stress wave propagation-based inspection technology originally developed in New Zealand. This technology evaluates each pole’s health in under a minute using stress wave analysis, providing data-rich, repeatable results
How It Works
At the heart of technology, which is called Poletest from THOR, is a rugged field kit and a data-driven analytics platform. The test itself is simple: a calibrated hammer hit sends a stress wave through the pole, which is captured by sensors and interpreted through its algorithms. The result is a "Pole Health Index" (PHI), an objective metric that reflects the structural integrity and serviceability of the asset. The analysis considers the entire length of the pole and variable fiber strength, factors that are often overlooked but crucial to understanding a pole’s true condition.
“Repeatability is a core benefit,” noted Robert Perreira, KIUC Utility Inspector, who led field implementation. “We can revisit a pole in five years and get a consistent, comparative reading, something we couldn’t reliably do before.”
The deployment helped in the following areas:
- Time: Each test took under one minute, reducing labor and allowing for greater inspection coverage in a shorter time frame.
- Data integrity: With auditable, cloud-based records, the team could prioritize maintenance and allowed them to plan inspection programs more effectively. It also helped KUIC to know where and when a pole was last tested.
- Safety and sustainability: Eliminating the need for intrusive integrity checks at the groundline preserved the pole’s structural integrity and reduced environmental impact.
- Replacement Costs: Accurate assessments meant fewer poles were replaced unnecessarily.
The analytics portal enabled KIUC to visualize the entire pole network, filter results by PHI score, and model replacement scenarios for budgeting and wildfire readiness.
