G.I.S. Implementation on Dam-Break Flood Vulnerability Analysis – A Case Study of Cătămărăști Dam, Botoșani, Romania.

Abstract

Flood analysis has become a very important research topic in the last decade, mainly due to the spatial and temporal rainfall variability and river discharge. The construction of dams on rivers has helped in keeping a certain amount of safety from such phenomena among other advantages. However, the consequences of failure of these structures could generate massive damages such as loss of human lives and property damage or destruction. In order to mitigate the eventual threat of a dam-break flood and come up with strategies concerning the eventuality of the event, it is highly important to estimate the characteristics of the potential dam-break generated flood. For this study, a HEC-RAS two-dimensional model was used based on a LiDAR digital elevation model, in order to assess the dam-break flood vulnerability of the inhabited areas downstream of Cătămărăști Dam, an earth dam with a clay sealing, located 3 kilometers upstream of the first locality and the periphery of Botoșani city. The simulation involves the breaking of the dam at full capacity, namely 12.4 million cubic meters and the modelling of its entire water volume downstream movement. The results show the flood extent and the water depth, the vulnerable inhabited areas and land cover areas, exposed to the potential threat of the simulated flood, on the inhabitants located near the riverbed, with a total of 780.92 ha, a number of 698 households, constructions, several roads and bridges, vulnerable to the floods. For mapping the results and other GIS related tasks, ArcGIS software was used. Due to the given proximity of the inhabited areas downstream and the volume of Cătămărăști reservoir, the modelled scenario can be a probable event.

Keywords

• HEC-RAS
• dam-break
• simulation
• vulnerability
• management