Study used TUFLOW hydraulic model from Williamtown Salt Ash FS Review (BMT WBM, 2012). The key updates for the revised modelling include: * Updated topographical data using the 2013 LiDAR data set acquired by NSW Land and Property Information. Previous modelling utilised the 2007 LiDAR data set acquired by NSW Department of Planning. * Update of Hunter River design flood flows through revised flood frequency analysis (FFA) at Raymond Terrace. An FFA from a 1994 study has been used as the basis for design flood estimation in the Hunter Estuary for subsequent studies and has now been revised as part of the current study; * Additional climate change scenario modelling. This included establishment of design flood conditions consistent with definition of design flood planning levels in current Council planning policy.