It’s 42 degrees Celsius, it hasn’t rained for weeks and the risk of forest fires is high. In this dusty corner of southeastern Spain, the grass has turned yellow in August and crop fields are dying in the heat after months without rain. Walking down the street feels like your skin is burning with the heat.
But on the outskirts of Ribarroja, a small town near Valencia, there is an unusual line of defense against a possible fire. Towering above the trees near the outskirts of town is a series of huge green spiers resembling streetlights. They act as giant water sprinklers, showering the trees and bamboo plants below with recycled water to reduce the risk of fire. They are supplied with recycled water from the nearby houses in Ribarroja and neighboring Paterna.
This is the largest defense system against forest fires in Europe, consisting of 40 towers surrounding the towns, the largest of which is 24 meters high. Known as the Guardian Project, the project protects urban areas surrounded by trees or other vegetation from the devastating effects of wildfire by hydrating vegetation and creating a natural barrier. As climate change increases the risk of wildfires across the continent, Guardian-style defenses could become a staple in high-risk parts of Europe in the future.
Watering vegetation can delay the spread of a fire because plants with greater amounts of moisture require more of a wildfire’s energy. Other factors influence the spread of a wildfire – wind speed, for example – is crucial – but in general, the drier the vegetation, the faster a fire will devastate the landscape.
“Water consumes some of the energy of a fire,” says Ferrán Dalmau, CEO of forest fire consultancy Medi XXI GSA, which developed the Guardian system. “When a plant is more hydrated, it slows the fire down.” But Dalmau warns that the system won’t put out a fire. Guardian can slow and control a fire, but does not replace the need for firefighters to intervene.
In fact, hiding in the undergrowth is Guardian’s second line of defense: a set of sensors. These provide the local fire protection authorities with real-time information about the air humidity in the systems and the resulting fire risk around the clock. Based on this information, the fire brigades are put on a higher alert level when the danger increases. Citizens can also be informed about the risk of fire via the Telegram news service.
After showing me the Guardian system on site, Dalmau takes me to his office and shows me how, thanks to these sensors, the system can indicate areas that could be affected by a fire and simulate how the fire might develop. Dalmau shows me a computer graphic of the area we just crossed. The irrigated area is brown in color, meaning it’s safer, but the rest around it is bright red – meaning it would be at maximum fire risk. An algorithm calculates the fire risks.
After a prolonged drought and searing temperatures, 2022 was the worst year for wildfires in Spain. According to the European Forest Fire Information System, 275,000 acres — about four times the area of New York City — have burned so far this year, more than four times the state annual average. Tens of thousands of people had to evacuate their homes as the flames raged.