Derivation of hydrologic frequency curves

The new approach described and assessed consists of making the rainfall process the primary input to the derivation of frequency curves rather than using streamflow records. A continuous series of rainfall events are simulated; the storms likely to produce large peak flows are routed through the catchment; the appropriate runoff characteristics are obtained from the derived hydrographs; and the frequency distribution is constructed either of the annual series or partial duration series of extreme events.