Flood frequency analysis using historical data: accounting for random and systematic errors |
| |
| Authors: | Luc Neppel Benjamin Renard Michel Lang Pierre-Alain Ayral Denis Coeur Eric Gaume |
| |
| Institution: | 1. UMR HydroSciences Montpellier – Universite Montpellier II – Place Eugene Bataillon, CC MSE , F-34090, Montpellier Cedex 5, France neppel@msem.univ-montp2.fr;3. Hydrology–Hydraulics, Cemagref Lyon , 3 bis Quai Chauveau, CP 220, F-69336, Lyon Cedex 09, France;4. Ecole des Mines d'Alès, LGEI , 6 Avenue de Clavières, F-30100, Alès, France;5. ACTHYS Diffusion , 253, Chemin de Plate-Rousset, F-38330, Biviers, France;6. LCPC, Route de Bouaye , BP 4129, F-44341, Bouguenais Cedex, France |
| |
| Abstract: | Abstract Flood frequency analysis based on a set of systematic data and a set of historical floods is applied to several Mediterranean catchments. After identification and collection of data on historical floods, several hydraulic models were constructed to account for geomorphological changes. Recent and historical rating curves were constructed and applied to reconstruct flood discharge series, together with their uncertainty. This uncertainty stems from two types of error: (a) random errors related to the water-level readings; and (b) systematic errors related to over- or under-estimation of the rating curve. A Bayesian frequency analysis is performed to take both sources of uncertainty into account. It is shown that the uncertainty affecting discharges should be carefully evaluated and taken into account in the flood frequency analysis, as it can increase the quantiles confidence interval. The quantiles are found to be consistent with those obtained with empirical methods, for two out of four of the catchments. Citation Neppel, L., Renard, B., Lang, M., Ayral, P.-A., Coeur, D., Gaume, E., Jacob, N., Payrastre, O., Pobanz, K. & Vinet, F. (2010) Flood frequency analysis using historical data: accounting for random and systematic errors. Hydrol. Sci. J. 55(2), 192–208. |
| |
| Keywords: | historical flood Bayesian flood frequency analysis discharge errors Mediterranean catchment |
|
|
