Abstract:
For planning, development and operation of different types of water resources schemes including the hydropower projects, applications of new and advanced methodologies of prediction of floods of various return periods for ungauged, poorly gauged and gauged catchments is of a great importance. For this purpose, L-moments based regional flood frequency approaches hold a great potential as these are demonstrably superior to the other approaches. In this paper, annual maximum peak flow data of l l stream flow gauging sites of the Sub-Himalayan region are screened using the Discordancy measure (Di) and homogeneity of the region is tested employing the heterogeneity measure (H). Robust frequency distribution is identified based on L-moment ratio diagram. For prediction of floods of various return periods for gauged catchments, a regional flood frequency relationship is developed based on the robust frequency distribution. For ungauged catchments, the developed relationship is coupled with a regional relationship between mean annual peak flood and catchment area.
