(Proceedings, World Congress on Natural Disaster Mitigation, February 2004, New Delhi, Vol. 2, pp. 493–497).
Flash floods are very common in hilly areas. There are cases where flash flood created disturbance in the river in such a way that a temporary dam is formed across river leading to catastrophy on the down stream side on removal. In this process bridges can also collapse, affecting connectivity of the area. These type of floods have been observed in last five years in Siang Valley (Arunachal Pradesh) and Satluj Valley (Himachal Pradesh). There had been serious setback to the road communication system due to collapse of these bridges in the area. Also the activities on bridges under construction got affected. Siang Valley in Arunachal Pradesh state had a flash flood on 11 June 2000 where whole valley was cut off from either side due to collapse of eleven road and foot bridges including longest stiffened suspension bridge of country (NOBO Bridge).
Flash floods, Hilly areas, Temporary dam, Collapse, Connectivity, Road communication
