Floodwaters destroy road and pedestrian bridge in Somero

A severe thunderstorm on Sunday cut off Turuntie road in Somero, southwest Finland, after floodwaters collapsed a section of the road and swept away a newly built pedestrian bridge, Yle reports.

The downpour overwhelmed a culvert under the road, causing the water flow to erode the soil beneath the pavement until the surface gave way, according to Tero Ahokas, a pavement engineer at the Southwest Finland Vitality Centre.

“The situation was completely exceptional,” Ahokas said. “That kind of culvert isn’t designed to handle the volume of water that came through.”

The road and bridge, completed just a year ago, were in good condition, and no construction or maintenance defects contributed to the collapse. Engineers may consider enlarging the culvert during repairs, but the overall structure met standard requirements.

Inspections were delayed on Monday due to lingering floodwaters and ongoing risk of further collapses. Full repairs, including rebuilding the bridge, are expected to take weeks rather than days, with a detailed plan to be finalised by the end of the week.

Such large-scale road collapses are extremely rare in Finland, Ahokas noted, though minor edge failures can occur during heavy rainfall. Similar incidents are more commonly linked to spring floods, particularly in Ostrobothnia, where meltwater can overtop roads.