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SIMULATING FLASH FLOODS IN URBAN AREAS USING TWO-DIMENSIONAL HYDRAULIC MODEL
Abstract
Urban floods, which are most often caused by intensive rainfall and the fast formation of surface runoff, cause great damage to the urban population and infrastructure. Due to the stochastic (random) nature of precipitation, it is not entirely possible to achieve reliable operation of sewer systems. We can only try to design and operate them in the most reliable way. Urbanization and changes in climatic conditions are one of the main factors for increasing the frequency of flash and rain floods in urban conditions. According to the World Meteorological Organization (WMO), flash floods are among the most dangerous natural phenomena with the highest mortality (deaths / affected people) and cause devastating property damage every year. Flash floods modeling are an important tool for forecasting the phenomena and for effective flood mitigation. Due to the physical characteristics of convective precipitation, the time to forecast flash and rain floods, in a contrast to river floods, is very short. This article presents an approach to modeling flash floods in an urban area. The method is performed using two-dimensional (2D) modeling with HEC-RAS software. The computational mesh for terrain representation is 0.05 m. Detailed terrain data for mesh generation in the 2D model was provided by Drone. Land cover information from CLC 2018 was used to determine the Manning coefficients. A simulation was conducted including main streets and buildings in the area in order to evaluate the influence of streets in the flooding. Two more values of the Manning coefficient were added manually, one for the riverbed and one for buildings and streets. Data from meteorological measurements were used to evaluate the 24 hourly maximum of the rain with probability 5%, 1% and 0.1%. Flood maps from the simulation of 20-, 100- and 1000-year-hyetograph are presented.
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References6
https://consult.environment-agency.gov.uk/engagement/bostonbarriertwao/results/appendix-5---environment-agency--2010--hydraulic-analysis-and-design--practical-application-of-hydraulic-modelling.-in-r.j.-crowder--fluvial-design-guide.pdf
HEC-RAS 5.0 Reference Manual, Version 5.0, February 2016
Li, Z., Zhu, Q., Gold, C., Digital terrain modeling: principles and methodology, CRC Press, Boca Raton, FL, 2005
Ding, Y., Jia, Y., Wang, S., Identification of Manning’s roughness coefficients in shallow water flows. Journal of Hydraulic Engineering, 130(6), 501-510, 2004
Герасимов, С., “Хидрологичен наръчник” том II, София 1980 г.
Balbastre-Soldevila, R., García-Bartual, R., Andrés-Doménech, I., A Comparison of Design Storms for Urban Drainage System Applications, FDG2-Ch7, 2009
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