Using 2D Hec-RAS Modeling for Modelling Major Flood Events (Post-2000) Downstream the Stânca Costești Reservoir (Middle Sector of Prut River)

Abstract

Floods have been a significant concern for Romania, with notable events post-2000. These floods have been influenced by several factors, such as climate change, massive deforestation, inadequate urban planning and inadequate hydraulic infrastructure. The regions in the north-east of the country were particularly affected, suffering serious consequences for local communities, agriculture and infrastructure. The floods caused significant losses, including human and material losses. As main response, the Romanian authorities implemented 2007/60/EC Directive whose objective is to assess and manage major flood events. Considering the national legislation, the experiment consists in reconstructing the most destructive flood events which happened on Prut River. Along the Prut River, the most important flood events (post-2000) were recorded in 2005, 2008, 2010 and 2020. Using the HEC-RAS hydraulic modeling software, four different 2D hydraulic scenarios (2D-HS) were developed: 2D-HS1 (2005 flood event), 2D-HS2 (2008 flood event), 2D-HS3 (2010 flood event), 2D-HS4 (2020 flood event). Using the maximum flood extent, the total affected areas were extracted. The flood hazard was assessed by using the Australian Institute for Disaster Resilience (AIDR) methodology which use the Depth*Velocity (D*V) raster. The results shows that 497.7 km2 were affected in the case of 2D-HS1, 569.3 km2 were affected in the case of 2D-HS2, 553.4 km2 were affected in the case of 2D-HS3 and 535.4 km2 were affected in the case of 2D-HS4.

Keywords

• flood modeling
• 2d hec-ras
• prut river
• hazard assessement