Studded tires accelerating road wear as climate change and speed worsen damage

Finnish roads are deteriorating faster due to a combination of studded tires, climate change, heavier vehicles, and higher speeds, while maintenance funding is set to drop significantly next year, Yle reports.

Road ruts caused by studded tires are deepening at an increasing rate, particularly on busy highways, according to Katri Eskola, a road maintenance expert at the Finnish Transport Infrastructure Agency. The problem is most visible in spring, when warmer, wetter winters—linked to climate change—soften asphalt, making it more susceptible to wear.

“Wet asphalt wears faster than dry asphalt under studded tires,” Eskola explained. She noted that modern vehicles are also heavier, further accelerating damage, while summer speed limits—when studded tires may still be in use—intensify the problem.

Funding for road repairs will fall sharply in 2025, dropping to around €170 million, a significant reduction from current levels. This year, maintenance and markings received €279 million, including an additional €100 million from a temporary government repair debt program. Rising oil prices, which affect bitumen costs, are also increasing repair expenses.

On high-traffic routes like Highway 4 in Oulu, where daily traffic reaches 50,000 vehicles, ruts can deepen by 4–5 millimeters annually—far above the average 0.5–2 millimeters. Repairs are typically needed when ruts exceed 18 millimeters, requiring patching or resurfacing every 3–5 years, said Ari Junkkari, a road maintenance specialist at the Northern Finland Centre for Economic Development.

Deep ruts pose safety risks by collecting rainwater, increasing the danger of hydroplaning. Liikenneturva, Finland’s traffic safety agency, advises drivers to avoid ruts when possible, as excessive speed and worn tires heighten risks even in light rain. While lane-keeping assist systems can help, disabling them may allow drivers to steer clear of ruts, promoting more even road wear.