Methodology for post-event analysis of flash floods – Svacenický Creek case study

Abstract

In this paper a methodology for a post-event analysis of a flash flood and
estimation of the flood peak and volume are developed and tested. The selected flash flood
occurred on the 6th of June, 2009 in the Svacenický Creek Basin. To understand rainfallrunoff
processes during this extreme flash flood, the runoff response was simulated using
the spatially-distributed hydrological model KLEM (Kinematic Local Excess Model). The
distributed hydrological model is based on the availability of raster information about the
landscape’s topography, soil and vegetation properties and radar rainfall data. In the
model, the SCS-Curve Number procedure is applied to a grid for the spatially-distributed
representation of the runoff-generating processes. A description of the drainage system’s
response is used to represent the runoff’s routing. The simulated values achieved by the
KLEM model were comparable with the maximum peak estimated on the basis of the
post-event surveying. The consistency of the estimated and simulated values from the
KLEM model was evident both in time and space, and the methodology has shown its
practical applicability.