Author(s): T. Malone
Linked Author(s):
Keywords: Floods; Dams; Design; Seqwater
Abstract: In 2008, the Queensland Government assigned responsibility for the storage and supply of bulk water supplies in South East Queensland to Seqwater. This resulted in the organisation's portfolio of dams increasing from 3 to 25 with catchment areas from less than 1 to over 7,000 square kilometres. The currency of the design flood hydrology studies range from November 2003 to October 2009 and utilized a variety of hydrologic models including WT42, RAFTS, RORB and URBS. Critical durations range from a few hours to a few days. Design rainfalls were based upon CRCFORGE and GSDM/GTSMR methodology. This paper summaries the methods and models used to derive the Probable Maximum Precipitation Design Flows for the storages. It examines the uncertainties associated with the design process and presents an approximate method for estimating extreme design floods for catchments in South East Queensland.
Year: 2011