Landslides in coastal areas of Italy

Abstract

Abstract Of the more than 8000 km of coasts in Italy, about 35% consist of cliffs and rocky shores. On them many villages are located, some of them dating back to Roman or Greek times. Typical natural hazards along these coastal areas are rock falls, slides and debris flows. They induce locally extremely high levels of risk, as shown by the many disasters that have occurred in recent time. This paper provides a first portrait over the whole of Italy of (1) the number and distribution of coastal landslides; (2) their typologies; (3) their state of activity; (4) the most common damage and exposed elements; and (5) the most typical mitigation measures. This information has been largely derived from the IFFI archive (Italian Landslides Inventory). Geographic information system processing has allowed us to identify 4135 landslides affecting a large portion of the Italian cliffed coasts. The damage evaluation, based on the AVI archive (inventory of information on sites historically affected by landslides and floods in Italy for the period 1918–2000), has shown the extent of the problem: there have been 408 casualties in the 20th century and 713 significant disruptions of the rail and road networks. A more detailed analysis has been carried out in three sample areas to illustrate the basic factors controlling the genesis and evolution of slope instabilities in the various coastal settings.