Universidad Complutense de Madrid
E-Prints Complutense

Quantification of flash flood economic risk using ultra-detailed stage–damage functions and 2-D hydraulic models

Impacto

Downloads

Downloads per month over past year

Garrote Revilla, Julio and Alvarenga, F. M. and Díez-Herrero, A. (2016) Quantification of flash flood economic risk using ultra-detailed stage–damage functions and 2-D hydraulic models. Journal of Hydrology, 541, A . pp. 611-625. ISSN 0022-1694 ; ESSN 1879-2707

[img] PDF
Restringido a Repository staff only

7MB

Official URL: https://www.sciencedirect.com/journal/journal-of-hydrology/vol/541/part/PA




Abstract

The village of Pajares de Pedraza (Segovia, Spain) is located in the floodplain of the Cega River, a left bank tributary of the Douro River. Repeated flash flood events occur in this small village because of its upstream catchment area, mountainous character and impermeable lithology, which reduce concentration time to just a few hours. River overbank flow has frequently caused flooding and property damage to homes and rural properties, most notably in 1927, 1991, 1996, 2001, 2013 and 2014. Consequently, a detailed analysis was carried out to quantify the economic risk of flash floods in peri-urban and rural areas. Magnitudes and exceedance probabilities were obtained from a flood frequency analysis of maximum discharges. To determine the extent and characteristics of the flooded area, we performed 2D hydraulic modeling (Iber 2.0 software) based on LIDAR (1 m) topography and considering three different scenarios associated with the initial construction (1997) and subsequent extension (2013) of a linear defense structure (rockfill dike or levee) to protect the population. Specific stage–damage functions were expressly developed using in situ data collection for exposed elements, with special emphasis on urban-type categories. The average number of elements and their unit value were established. The relationship between water depth and the height at which electric outlets, furniture, household goods, etc. were located was analyzed; due to its effect on the form of the function. Other nonspecific magnitude–damage functions were used in order to compare both economic estimates. The results indicate that the use of non-specific magnitude–damage functions leads to a significant overestimation of economic losses, partly linked to the use of general economic cost data. Furthermore, a detailed classification and financial assessment of exposed assets is the most important step to ensure a correct estimate of financial losses. In both cases, this should include a consideration of the socio-economic and cultural conditions prevailing in the area, as well as the types of flood that affect it


Item Type:Article
Uncontrolled Keywords:Flash floods, Magnitude–damage functions, Direct economic losses, 2D hydraulic models, Mountain villages, Natural hazards
Subjects:Sciences > Geology > Hidrology
ID Code:51713
Deposited On:05 Mar 2019 10:58
Last Modified:28 Jan 2020 08:17

Origin of downloads

Repository Staff Only: item control page