Mondego dike rupture in Coimbra attributed to protection and maintenance failures (eco.sapo.pt)

• Only one of three siphon dikes functioned fully
• Tree trunks at A1 bridge raised water level by estimated 30 cm
• Vegetation on slopes weakened dike structure

"A working group from the University of Coimbra (UC) analyzed the February 2026 rupture of the Mondego River dike. Preliminary findings identify three main causes: incomplete operation of protection systems, blockage by tree trunks at the A1 bridge pillars, and vegetation growth on inner slopes. The group states that addressing any one of these could have prevented the rupture. Repairs, a maintenance program, and a dedicated team are recommended. A book with full findings is expected by September/October 2026."