In the hills and canyons of the Tonto National Forest, 112 new "spies" are quietly watching for the next big blaze.
A pilot network of sensors is now scanning dryness across the forest around the clock, giving land managers and utilities a near-real-time read on where fuels are most likely to ignite and spread. The collaboration between Salt River Project (SRP), Northern Arizona University and Albuquerque startup Growvera has placed devices at six locations to measure dead and living vegetation, plus soil moisture at multiple depths. SRP funded the work through an innovation program and plans to keep the pilot running for at least a year, officials say. The goal is to build detailed field data that can sit alongside weather models and satellite maps so crews know exactly where to thin fuels, stage resources or adjust power operations.
According to ABC15, the array covers six sites and 112 sensors that continuously track dead-fuel moisture, live-plant moisture and soil moisture at three depths to create a fuller picture of fuel conditions. Growvera product engineer Asher May told the outlet, "This is really important for fire risk," while Northern Arizona University researcher Salli Dymond said the system can deliver data both ahead of a fire and right at the fire front to show how ground conditions shift. ABC15 reports the pilot was funded by SRP's Innovation and Development Program and is expected to run for at least one year. Researchers say that if the approach holds up, it could be scaled to other forests around Arizona.
How the Sensors Work
Growvera's DRYLINE platform uses impedance-based plant sensing that sits directly in dead and live fuels to generate field-level moisture readings, according to Growvera's website. The sensors send data every hour through LoRaWAN or cellular networks to an analytics dashboard that maps fuel dryness and highlights circuits where dry fuels and forecast winds combine into a higher risk. The company pitches the data streams as a way to ground-truth remote estimates and to give utilities more precise and defensible Public Safety Power Shutoff decisions.
Why SRP Is Watching the Tonto
SRP is framing the pilot as both a wildfire mitigation effort and a grid-resilience play. The utility manages a 13,000-square-mile watershed and provides water and power to more than two million people in central Arizona, according to SRP. Barry Johnson, SRP's wildfire mitigation specialist, told ABC15, "We want to try to keep the power on." That need for better ground data is being underscored in real time by the Sycamore Fire north of Globe, which has burned thousands of acres and pushed toward key transmission corridors this month, according to AZFamily.
What Comes Next
In the months ahead, researchers will stack the sensor feeds against weather-model outputs and field observations to test whether live fuel-moisture telemetry sharpens predictions of fire behavior and risk to power infrastructure. If the pilot proves itself, utility and research partners hope to move the concept beyond Tonto, building out a broader web of ground-truth stations across other state forests for land managers and fire-weather forecasters.
Growvera's site also highlights the Public Safety Power Shutoff angle, saying hourly field readings can help utilities narrow the scope of shutoff decisions and support faster re-energization once fuels begin to re-wet.
