The components of the study are to:

• collate available historical flood related data;
• analyse historical rainfall and flooding data;
• undertake a community consultation program;
• develop robust computational hydrologic and hydraulic models and calibrate them against multiple historical events;
• undertake a flood frequency analysis based on the historical record
• determine the flood behaviour including design flood levels, velocities and flood extents within the catchments;
• to assess the sensitivity of flood behaviour to potential climate change effects such as increase in rainfall intensities
• to assess the floodplain categories in accordance with Council policy and undertake provisional hazard mapping; and
• to determine and map the flood planning area in accordance with the floodplain development manual

MODELLING SUMMARY

The study comprises two distinct modelling components:

• WBNM (Hydrologic) – The model was used to calculate the flow hydrographs for input into the TUFLOW model.
• TUFLOW (Hydraulic) – The 2D hydraulic model was used to assess the complex flow regimes of Paterson River and its tributaries and how these flows interact with the floodplain and levee system.