Assessing the flooding hazard through a probabilistic approach including earthen levees vulnerability estimate

Levees collapse cause huge financial and social losses, especially in highly developed areas of many countries. Since that 2563 floods occurred in Europe between 1980 and 2010 (EEA, 2018), the European Parliament issued the Floods Directive, approved in 2009, in which EU Member States are invited to minimise this risk of failure, improving methods and finding simple solutions for large-scale application. For this reason, the scientific community is gradually performing stochastic approaches allow a large number of simulations runs in a Monte Carlo framework, providing the basis for a probabilistic risk assessment considering also the influence of levee breaches on the flood risk (Apel et al., 2006, Castellarin et al., 2011). Indeed, in many studies, seepage analyses account only the hydraulic boundary conditions, i.e.  the water head upstream of the embankment (Tracy et al., 2016, 2020).  

In this context, the present work is focused on the evaluation of the residual flood risk through the analysis of earthen levees’ seepage vulnerability. In particular, the levee fragility curves determined with the use of simplified and expeditious approaches and those assessed by using geotechnical finite element models (i.e. PLAXIS 2D) are compared. Furthermore, the goal of this study is to find the relation between the frequency of levee’s failure due to hydraulic and geotechnical conditions, to aim of define the conditional probability of the residual flood risk.

 

References

Apel, H., Annegret, H. T., Bruno, M., & Günter, B. (2006). A probabilistic modelling system for assessing flood risks. Natural Hazard, 38, 79-100. https://doi.org/10.1007/s11069-005-8603-7.

Castellarin, A., Di Baldassare, G., & Brath, A. (2011). Floodplain management strategies for flood attenuation in the River Po. River Research and Applications, 27(8), 1037 –1047. https://doi.org/10.1002/rra.1405.

EEA, European Environment Agency. (2018). European past floods [Online]. Copenhagen, Denmark: Author. Retrieved from https://www.eea.europa.eu/data-and-maps/data/european-past-floods/ .

Tracy, F.T., Brandon, T. L., Corcoran, M.K. (2016). Transient seepage analyses in levee engineering practice, Technical Report TR-16-8, U.S. Army Engineer Research and Development Center, Vicksburg, MS, http://acwc.sdp.sirsi.net/client/en_US/search/asset/1050667.

Tracy, F.T., Ryder, J.L., Schultz, M.T., Ellithy, G.S., Breland, B.R., Massey, T.C., Corcoran, M.K. (2020). Monte Carlo Simulations of Coupled Transient Seepage Flow and Soil Deformation in Levees. Scalable Computing Practice and Experience 21(1):147-156. https://doi.org/10.12694/scpe.v21i1.1629.