Three consecutive rainy events badly affected coastal ranges of Catalonia, Eastern Spain. Rainfall records exceeded 200 mm in 48 h in most of the region, while values over 300 mm were reached in some spots. In basins of less than 100 km² measured unit river discharges ranged from 3 to 7 m³/s.km². These values are among the highest recorded in the region. Most of the rivers behave like torrents. In upper river reaches, the steep bed slope led to bed scouring and the mobilization of large boulders (over 1 m³) while on lower reaches, aggradation made the former flood plain to rise and to built alluvial fan. This scour- deposition dynamics caused severe damage on river training works and nearby infrastructures.