Stochastic analysis of high flows in some Central British Columbia rivers

High flows derived from the partial duration series were analysed in terms of the probability distributions of magnitude, frequency, duration, and the time of occurrence. Simple methods of representing the timing and duration of high flows as stochastic variables are presented. Existing stochastic models are applied to the probability distributions of the annual frequency of high flows and their magnitudes. A consideration of the statistical properties of the above stochastic variables leads to the development of a technique with which floods exceeding any higher level of interest may be investigated without resorting to a reanalysis of the historical data. The proposed methodology was applied to the daily streamflow records of three rivers located in diverse hydrological environments in Central British Columbia. Good agreement between the computed and the observed data in all eases reflects the applicability of the technique.