Author(s): Brett C Phillips, Stephen Yu
Linked Author(s): Brett C Phillips
Keywords: Rating tables; Flow gauging; Bayesian flood frequency analysis;
Abstract: In 2012 a draft flood study was undertaken to define the nature and extent of flooding and flood hazards for a range of design floods in the City of Dubbo which is located on the banks of the Macquarie River in central New South Wales, Australia. The study area included the floodplains of the Macquarie River and the lower Talbragar River located around 6 km north of Dubbo. Located upstream of Dubbo, the major Burrendong Dam was commissioned in 1965 and it has affected the flood behaviour of the Macquarie River downstream of the dam. In May 2015 additional assessments were undertaken including the review of 44 rating tables, flow gaugings and flood frequency analysis at Station 421001 Macquarie River at Dubbo. These assessments are described. Five Pre-Dam and Post-Dam annual peak flow scenarios were assembled and subjected to Bayesian flood frequency analysis The outcomes of the additional assessments ,which were subject to peer review are outlined and the updated assessment of flooding and flood hazards for a range of design floods in the City of Dubbo are overviewed. It is concluded that the additional assessments should increase the confidence of the community when adopting the updated flood study for the City of Dubbo.