J ．　 Fac ．　 Agr． ，　 Kyushu　Univ． ，　 45　（2） ，　 557－564　（2001） Hydrograph Recession　Analysis　using　Wavelet　lhransform＄

（Receiveel October “？i ， eOOe as？zd accepted Nevee7mber f O ， SOeg） A technique for determiming hydrograph recession eharacteristicS is presented based on the wavelet transforms analy＄is ． Like a signal ， a fiood hydrograph （ram be decomposed into a nurnber of wavelet compon（p．nt，s ． By using the wavelet component value．s in the form of wavqdet maps ， the recession characteristics such as a reeession constant and a cut－off frequeney are easily det，ermined ． The tG¢hnique is dernonstrated on three catchments ranging from small to large catehment areas at eastern New South Wales ， Australia ． The ．proposed method gSves promising results and minimizes a number of probleins assoclated with hydrograph reee＄sion a貝alys烹＄