Regional Flood Frequency Analysis Based on L-Moment Approach (Case Study Tisza River Basin)

Floods are one of the most common natural hazards and as such, they are causing a great loss of human life as well as great economic damages. Flood frequency analysis (FFA) is still an active and popular field of research among geographers. In this study we have performed regional flood frequency analysis (RFFA) using the L-moments method and annual maximum series (AMS) of mean daily discharge data for five stations in Tisza River basin for dependable prediction of flood quantiles. Floods were defined as events over selected threshold level which was set at Q10%. Based on L-moments ratio diagrams and its goodness-of-fit statistic, the Pearson type III distribution is identified as the best-fit distribution for the Tisza River basin. Results of this paper can be used as guideline for future research on establishing the official FFA distribution for the entire Tisza river basin which will improve international cooperation on the fields of environmental monitoring, water management and flood prevention policies.