Spatial and temporal scales of occurrence of flash floods make these events particularly difficult to observe by means of conventional measurement networks of rain and discharge. As a consequence, post-event surveys play an important role in the analysis of flash floods: they permit assessing peak discharge in ungauged streams, reconstructing the time evolution of the floods and documenting their geomorphic effects. Surveys of flash floods are currently carried on in the frame of the HyMeX project (www.hymex.org), with the aim of extending databases implemented in previous projects (e.g. Hydrate, 6th Framework Programme, www.hydrate.tesaf.unipd.it), and improving the understanding of flash flood formation in the Mediterranean. Four floods have been documented from 2010 to 2012 by means of post-event field observations and analysis of hydrometeorological data: Var Department (SE France), June 2010; Bacchiglione River basin (NE Italy), November 2010; Magra River basin (NW Italy), October 2011; Longano catchment (Sicily), November 2011. Flood magnitude in some catchment hit by these flash floods approaches maxima known in the Mediterranean region. The studied event have permitted focusing on different features relevant for the assessment of flash flood response: oinfluence of geological settings on flood response (Var Department); omorphological changes of channel beds and recruitment and transport of large wood (Magra River basin); ocomplex sediment dynamics and flood analysis in an urban context (Longano catchment). The flood of November 2010 in the Bacchiglione River basin has been considered, although it does not show all distinctive attributes of flash floods, because it was most severe flood in the studied area since November 1966 and it is representative of increased flood risk due to land use changes occurred in the last decades (expansion of industrial and urban areas). The contribution summarises the most relevant characteristics of the investigated events and outlines problems and perspective in post-event documentation of flash floods.
Documentation and analysis of recent flash floods in Italy and in southern France
Lorenzo Marchi;
2013
Abstract
Spatial and temporal scales of occurrence of flash floods make these events particularly difficult to observe by means of conventional measurement networks of rain and discharge. As a consequence, post-event surveys play an important role in the analysis of flash floods: they permit assessing peak discharge in ungauged streams, reconstructing the time evolution of the floods and documenting their geomorphic effects. Surveys of flash floods are currently carried on in the frame of the HyMeX project (www.hymex.org), with the aim of extending databases implemented in previous projects (e.g. Hydrate, 6th Framework Programme, www.hydrate.tesaf.unipd.it), and improving the understanding of flash flood formation in the Mediterranean. Four floods have been documented from 2010 to 2012 by means of post-event field observations and analysis of hydrometeorological data: Var Department (SE France), June 2010; Bacchiglione River basin (NE Italy), November 2010; Magra River basin (NW Italy), October 2011; Longano catchment (Sicily), November 2011. Flood magnitude in some catchment hit by these flash floods approaches maxima known in the Mediterranean region. The studied event have permitted focusing on different features relevant for the assessment of flash flood response: oinfluence of geological settings on flood response (Var Department); omorphological changes of channel beds and recruitment and transport of large wood (Magra River basin); ocomplex sediment dynamics and flood analysis in an urban context (Longano catchment). The flood of November 2010 in the Bacchiglione River basin has been considered, although it does not show all distinctive attributes of flash floods, because it was most severe flood in the studied area since November 1966 and it is representative of increased flood risk due to land use changes occurred in the last decades (expansion of industrial and urban areas). The contribution summarises the most relevant characteristics of the investigated events and outlines problems and perspective in post-event documentation of flash floods.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
