Simulation of flash flood peaks in a small and steep catchment using rain‐on‐grid technique

Abstract The frequency of extreme events is increasing as the consequences of climate change. In steep terrains, flash floods with high‐flow velocities induce erosion and sedimentation with potentially disastrous changes of flood path. Hence, the analysis of flash floods in steep terrains in terms o...

Full description

Bibliographic Details
Main Authors: Nitesh Godara, Oddbjørn Bruland, Knut Alfredsen
Format: Article
Language:English
Published: Wiley 2023-09-01
Series:Journal of Flood Risk Management
Subjects:
Online Access:https://doi.org/10.1111/jfr3.12898
_version_ 1797732645294047232
author Nitesh Godara
Oddbjørn Bruland
Knut Alfredsen
author_facet Nitesh Godara
Oddbjørn Bruland
Knut Alfredsen
author_sort Nitesh Godara
collection DOAJ
description Abstract The frequency of extreme events is increasing as the consequences of climate change. In steep terrains, flash floods with high‐flow velocities induce erosion and sedimentation with potentially disastrous changes of flood path. Hence, the analysis of flash floods in steep terrains in terms of inundation area and flow‐velocity to identify critical points becomes more important. The output of a flood simulation with a traditional hydrologic model provides the flood hydrograph which must be combined with a hydraulic model for downstream consequences. In small and steep catchments, the inflow contribution from every section of the water course can be important to determine where critical conditions may arise. In this study, rain‐on‐grid technique in the hydraulic model Telemac‐2D is used to simulate flash‐flood peaks with spatially distributed precipitation as input in a small and steep catchment in western Norway. Seven events were simulated and sensitivity tests on parameters were conducted. A 200‐year design flood was simulated to show the potential consequences in the catchment. The results show that calibrated models can satisfactorily reproduce peak flows and produce relevant information about water velocities and inundation which decision makers can use for mitigation measures. The paper explores the benefits and limitations through a description of model construction, calibration, and test of sensitivities.
first_indexed 2024-03-12T12:16:36Z
format Article
id doaj.art-53358fb116bb42f9ad0fc49df159776d
institution Directory Open Access Journal
issn 1753-318X
language English
last_indexed 2024-03-12T12:16:36Z
publishDate 2023-09-01
publisher Wiley
record_format Article
series Journal of Flood Risk Management
spelling doaj.art-53358fb116bb42f9ad0fc49df159776d2023-08-30T10:00:52ZengWileyJournal of Flood Risk Management1753-318X2023-09-01163n/an/a10.1111/jfr3.12898Simulation of flash flood peaks in a small and steep catchment using rain‐on‐grid techniqueNitesh Godara0Oddbjørn Bruland1Knut Alfredsen2Department of Civil and Environmental Engineering Norwegian University of Science and Technology 7491 Trondheim NorwayDepartment of Civil and Environmental Engineering Norwegian University of Science and Technology 7491 Trondheim NorwayDepartment of Civil and Environmental Engineering Norwegian University of Science and Technology 7491 Trondheim NorwayAbstract The frequency of extreme events is increasing as the consequences of climate change. In steep terrains, flash floods with high‐flow velocities induce erosion and sedimentation with potentially disastrous changes of flood path. Hence, the analysis of flash floods in steep terrains in terms of inundation area and flow‐velocity to identify critical points becomes more important. The output of a flood simulation with a traditional hydrologic model provides the flood hydrograph which must be combined with a hydraulic model for downstream consequences. In small and steep catchments, the inflow contribution from every section of the water course can be important to determine where critical conditions may arise. In this study, rain‐on‐grid technique in the hydraulic model Telemac‐2D is used to simulate flash‐flood peaks with spatially distributed precipitation as input in a small and steep catchment in western Norway. Seven events were simulated and sensitivity tests on parameters were conducted. A 200‐year design flood was simulated to show the potential consequences in the catchment. The results show that calibrated models can satisfactorily reproduce peak flows and produce relevant information about water velocities and inundation which decision makers can use for mitigation measures. The paper explores the benefits and limitations through a description of model construction, calibration, and test of sensitivities.https://doi.org/10.1111/jfr3.12898hydrological modellingrainfall‐runoff modelingTELEMAC‐2Dhydraulic modellingclimate change adaption
spellingShingle Nitesh Godara
Oddbjørn Bruland
Knut Alfredsen
Simulation of flash flood peaks in a small and steep catchment using rain‐on‐grid technique
Journal of Flood Risk Management
hydrological modelling
rainfall‐runoff modeling
TELEMAC‐2D
hydraulic modelling
climate change adaption
title Simulation of flash flood peaks in a small and steep catchment using rain‐on‐grid technique
title_full Simulation of flash flood peaks in a small and steep catchment using rain‐on‐grid technique
title_fullStr Simulation of flash flood peaks in a small and steep catchment using rain‐on‐grid technique
title_full_unstemmed Simulation of flash flood peaks in a small and steep catchment using rain‐on‐grid technique
title_short Simulation of flash flood peaks in a small and steep catchment using rain‐on‐grid technique
title_sort simulation of flash flood peaks in a small and steep catchment using rain on grid technique
topic hydrological modelling
rainfall‐runoff modeling
TELEMAC‐2D
hydraulic modelling
climate change adaption
url https://doi.org/10.1111/jfr3.12898
work_keys_str_mv AT niteshgodara simulationofflashfloodpeaksinasmallandsteepcatchmentusingrainongridtechnique
AT oddbjørnbruland simulationofflashfloodpeaksinasmallandsteepcatchmentusingrainongridtechnique
AT knutalfredsen simulationofflashfloodpeaksinasmallandsteepcatchmentusingrainongridtechnique