Evaluation of Methods for Estimating Long-Term Flow Fluctuations Using Frequency Characteristics from Wavelet Analysis

This study was aimed at exploring different indices to quantify flow fluctuations and calculate long-term indicators (L-FFI). Three approaches were considered the indicators: Method (1)—calculate annual index then average it; (2)—average characteristics index; (3)—calculate considering all available data. Wavelet analysis performed evaluate derived L-FFI. The evaluation based on period corresponding highest spectral power from wavelet transformation of seasonally differenced Strong negative positive correlations observed between L-FFI high- low-flow variations, respectively. correlation coefficient (R) L-FFIs frequency with maximum global showed that (2) consistently yielded most reliable results across various facets, having a determination 0.73 (R2) average. In regionalization using Ward method, it two largest dams (the Chungju Dam Uiam Dam) significantly differentiated other dams. Furthermore, similar clustering features. outcomes are expected facilitate water resource management.