A New Flash Flood Warning Scheme Based on Hydrodynamic Modelling

Abstract

Flash flooding is one of the most severe natural hazards and commonly occurs in mountainous and hilly areas. Due to the rapid onset of flash floods, early warnings are critical for disaster mitigation and adaptation. In this paper, a flash flood warning scheme is proposed based on hydrodynamic modelling and critical rainfall. Hydrodynamic modelling considers different rainfall and initial soil moisture conditions. The critical rainfall is calculated from the critical hazard, which is based on the flood flow depth and velocity. After the critical rainfall is calculated for each cell in the catchment, a critical rainfall database is built for flash flood warning. Finally, a case study is presented to show the operating procedure of the new flash flood warning scheme.

Flood Hazard Mapping Using the Flood and Flash-Flood Potential Index in the Buzău River Catchment, Romania

“…According to the National Administration of "Romanian Waters" and the National Meteorological Administration, the South East European Flash Flood Guidance System (SEEFFG), European Flood Awareness System (EFAS), and the Romanian Flash Flood Guidance System (ROFFG) are used to forecast flood and flash-floods for 8851 small river catchments. Previous researchers, who have used these indices to determine the areas prone to this type of natural risk phenomena, have shown the importance of knowing how to implement these indices to help local authorities to manage their interventions and minimize economic and human losses [35][36][37][38][39][40][41][42].…”

Applicability of Literature Values for Green–Ampt Parameters to Account for Infiltration in Hydrodynamic Rainfall–Runoff Simulations in Ungauged Basins

“…Hydrodynamic models are more and more used to simulate not only the flow and flooding areas of surface waters but also rainfall-induced overland flow in small catchments [3][4][5][6][7], the propagation of flash floods [8][9][10][11], and flood inundation in urban areas [12][13][14][15]. Additionally, to the calculation of the flow field, appropriate methods to represent the runoff generation are needed to establish an integrated hydrological-hydrodynamic model.…”

“…A good understanding of infiltration and its representation in models is crucial not only for the appropriate risk management of heavy rainfalls and flash floods but also for successful solutions of water harvesting and groundwater recharge [17]. Concerning the global trends of ongoing urbanization and climate change coming along with more frequent and more intense hydro-meteorological extremes in terms of floods and droughts, damages from inundations on the one hand and lowered groundwater tables and water stress, on the other hand, will increase and get more severe in future [4,10,18,19]. To mitigate these effects, so-called watersensitive or climate-adapted urban planning and water resources management strategies considering sustainable urban drainage systems (SUDS) [20,21] and low impact developments (LIDs) [22][23][24] are gaining increasing importance.…”

Applicability of literature values for Green-Ampt parameters to account for infiltration in hydrodynamic rainfall-runoff simulations in ungauged basins

“…Hydrodynamic models are more and more used to simulate not only the flow and flooding areas of surface waters but also rainfall-induced overland flow in small catchments [6,34,43,63,75], the propagation of flash floods [1,5,26,69], and flood inundation in urban areas [9,32,59,80]. Due to the enhanced accuracy and resolution of topographic data, the interest in using 2D hydrodynamic models is continuously increasing, and since different techniques of high-performance computing are developed to accelerate numerical computations, the powerful potential of shallow water models can be realized more and more and be used also in practical applications [33,48].…”

“…A good understanding of infiltration and its representation in models is crucial not only for the appropriate risk management of heavy rainfalls and flash floods but also for successful solutions of water harvesting and groundwater recharge [3]. Concerning the global trends of ongoing urbanization and climate change coming along with more frequent and more intense hydro-meteorological extremes in terms of floods and droughts, damages from inundations on the one hand and lowered groundwater tables and water stress, on the other hand, will increase and get more severe in future [26,30,34,39]. To mitigate these effects, so-called water-sensitive or climate-adapted urban planning and water resources management strategies considering sustainable urban drainage systems (SUDS) [20,74] and low impact developments (LIDs) [13,31,50] are gaining increasing importance.…”