Assessing Inundation Risks and Protection of Residential Territories in River Floodplains

Abstract

It is shown that the likely damage caused by inundation of residential areas and objects of higher hazard on river floodplains can be evaluated taking into account the inundation depth. A procedure of constructing inundation probability curves with the use of two-dimensional hydrodynamic models (based on the STREAM 2D CUDA software system (Russia)) and field observation data is considered. Data from hydrological gages in several rivers are used to show that the inundation recurrence curves can be approximated by some logarithmic functions. Formulas for determining the inundation risks of residential areas and integral risk characteristics are derived and substantiated. It is shown that, on the average for the objects considered in the study, the maximal risks correspond to inundation levels with exceedance probability of ~2%, and that the effective protection of residential areas in most cases should by designed for inundation levels with much smaller exceedance probability.