Assessment of Past Torrential Events Through Historical Sources

Abstract

The noun “torrent” to indicate a stream or a small river is quite uncommon outside Europe. The word comes from the Latin adjective “torrens” which means rushing, violent, fast. In torrents a substantial difference of magnitude exists between the low water periods – including a seasonal lack of surface water in ephemeral streams – and flood events capable of rearranging the river-bed topography heavily. The extremely low frequencies of important flow rates might cause the reduction of hazard perception and leads towards an incorrect land use and an unsafe management of the catchment. The collection of historical information of past events must be the starting point to deal with inhabitant security, land planning, and watershed management. Moreover, there are at least two other basic reasons which strengthen this need for analysis of those ‘torrential’ rivers located in steep lands.