Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007

<p>This paper analyses the Girona River (Spain) flash flood, occurred on the 12th of October 2007, combining hydrological and hydraulic modeling with geomorphologic mapping and post-flood survey information. This research aims to reproduce the flood event in order to understand and decipher th...

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Main Authors: Segura-Beltrán, F, Sanchis-Ibor, C, Morales-Hernández, M, González-Sanchis, M, Bussi, G, Ortíz, E
Format: Journal article
Published: Elsevier 2016
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author Segura-Beltrán, F
Sanchis-Ibor, C
Morales-Hernández, M
González-Sanchis, M
Bussi, G
Ortíz, E
author_facet Segura-Beltrán, F
Sanchis-Ibor, C
Morales-Hernández, M
González-Sanchis, M
Bussi, G
Ortíz, E
author_sort Segura-Beltrán, F
collection OXFORD
description <p>This paper analyses the Girona River (Spain) flash flood, occurred on the 12th of October 2007, combining hydrological and hydraulic modeling with geomorphologic mapping and post-flood survey information. This research aims to reproduce the flood event in order to understand and decipher the flood processes and dynamics on a system of overlapped prograding alluvial fans. The hydrological model TETIS was used to characterize the shape and dimension of the October 2007 Girona River hydrograph. Subsequently, the flood event was reproduced using the free surface flow module of the model RiverFlow2D. The combination of hydrological and hydraulic models was evaluated using post-flood surveys defining maximum flooded area and flood depths. Then, simulations with different peak discharges were carried out to estimate the hydro-geomorphologic response of the Girona River floodplain, through the identification of the activation thresholds in different geomorphic elements.</p> <p>Results showed that the unit peak discharge of the October 2007 flood event (5 m3 s-1 km-2) was among the largest ever recorded in the area, according to the existing literature. Likewise, the hydraulic model showed a good performance in reproducing the flood event (FitA = 76%, RMSE = 0.65 m and NSE = 0.6), despite the complexity of the case, an ephemeral and ungauged river. The model simulation revealed the existence of an activation pattern of paleochannels and alluvial fans, which was altered by the presence of some anthropogenic disturbances.</p> <p>This multidisciplinary approach proved to be a useful strategy for understanding flash flood processes in ungauged catchments. It allowed understanding the mechanisms governing floods in alluvial fans systems and it represented a solid contribution for early warning plans and risk mitigation policies.</p>
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spelling oxford-uuid:703c392b-a3d9-40de-b9c7-c623d54a1a2b2022-03-26T19:35:52ZUsing post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:703c392b-a3d9-40de-b9c7-c623d54a1a2bSymplectic Elements at OxfordElsevier2016Segura-Beltrán, FSanchis-Ibor, CMorales-Hernández, MGonzález-Sanchis, MBussi, GOrtíz, E<p>This paper analyses the Girona River (Spain) flash flood, occurred on the 12th of October 2007, combining hydrological and hydraulic modeling with geomorphologic mapping and post-flood survey information. This research aims to reproduce the flood event in order to understand and decipher the flood processes and dynamics on a system of overlapped prograding alluvial fans. The hydrological model TETIS was used to characterize the shape and dimension of the October 2007 Girona River hydrograph. Subsequently, the flood event was reproduced using the free surface flow module of the model RiverFlow2D. The combination of hydrological and hydraulic models was evaluated using post-flood surveys defining maximum flooded area and flood depths. Then, simulations with different peak discharges were carried out to estimate the hydro-geomorphologic response of the Girona River floodplain, through the identification of the activation thresholds in different geomorphic elements.</p> <p>Results showed that the unit peak discharge of the October 2007 flood event (5 m3 s-1 km-2) was among the largest ever recorded in the area, according to the existing literature. Likewise, the hydraulic model showed a good performance in reproducing the flood event (FitA = 76%, RMSE = 0.65 m and NSE = 0.6), despite the complexity of the case, an ephemeral and ungauged river. The model simulation revealed the existence of an activation pattern of paleochannels and alluvial fans, which was altered by the presence of some anthropogenic disturbances.</p> <p>This multidisciplinary approach proved to be a useful strategy for understanding flash flood processes in ungauged catchments. It allowed understanding the mechanisms governing floods in alluvial fans systems and it represented a solid contribution for early warning plans and risk mitigation policies.</p>
spellingShingle Segura-Beltrán, F
Sanchis-Ibor, C
Morales-Hernández, M
González-Sanchis, M
Bussi, G
Ortíz, E
Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007
title Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007
title_full Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007
title_fullStr Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007
title_full_unstemmed Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007
title_short Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007
title_sort using post flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models the flash flood of the girona river spain in 2007
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