The Flood Study had three main components:,

Chapter 2 contains background information including a brief description of the study catchment and its drainage system, details of previous flooding investigations, a summary of community consultation undertaken as part of this present study (refer Appendix A for details), and a brief history of flooding within the catchment. Chapter 3 deals with the hydrology of the Lane Cove River and Swaines Creek catchments, and describes the development of the RORB and DRAINS hydrologic models which were used to generate discharge hydrographs for input to the hydraulic model. Chapter 4 deals with the development of the TUFLOW hydraulic model which was used to analyse flood behaviour in the study area. Chapter 5 deals with the derivation of design discharge hydrographs, which involved the determination of design storm rainfall depths over the catchments for a range of storm durations and conversion of the rainfalls to discharge hydrographs. Chapter 6 details the results of the hydraulic modelling of the design floods. Results are presented as water surface profiles and plans showing indicative extents of inundation for a range of design flood events up to and including the PMF. A provisional assessment of flood hazard and hydraulic categorisation is also presented. (The assessment of flood hazard according to velocity and depth of floodwaters is necessarily “provisional”, pending a more detailed assessment which includes other flood related criteria, to be undertaken during the future FRMS.) The results of various sensitivity studies undertaken using the TUFLOW model are also presented, including the effects of changes in hydraulic roughness, partial blockage of the piped stormwater system, and potential increases in rainfall intensities and sea levels due to future climate change. This chapter also deals with the selection of Interim FPL’s for the study area. Chapter 7 contains a list of references. Chapter 8 contains a list of flood-related terminology that is relevant to the scope of the study. Appendix A provides details of the collection of historic flood data and describes the testing of the hydrologic and hydraulic models. Figures referred to in both the main report and the appendices are bound in a separate volume of the report (refer Volume 2).

The Raymond Terrace Flood Study has been prepared for Port Stephens Council (Council) to define the existing flood behaviour in the western Raymond Terrace catchments and establish the basis for subsequent floodplain management activities. The study will also assist Council in considering future upgrades to the drainage network and flood relief pump capacity to the Hunter River. This project has been conducted under the State Assisted Floodplain Management Program and received State financial support.

The activities comprising the present investigation included:,

This study updates the previous Wrights Creek Flood Study (Patterson Britton & Partners, 2007) and provides Council with a suitable platform for undertaking the next steps in the Floodplain Risk Management Process. The XP-RAFTS hydrologic model developed in the 2007 Flood Study has been adopted for this study. A TUFLOW hydraulic model of the catchment has been established using up to date survey of the ground levels and culvert and bridge structures. The TUFLOW hydraulic model has been used to reproduce the historical flood behaviour from events in 1995 and 2002 and to define flood behaviour for a range of design events. Actions undertaken as part of this flood study include: • collection of additional survey, • development of a TUFLOW hydraulic model, • definition of the design flood behaviour, • assessment of provisional hydraulic hazard, • assessment of hydraulic categorization, • assessment of the model sensitivity to parameter changes, • assessment of climate change impacts on model results, • assessment of sensitivity of model results to the new ARR 2016 design inputs, • community consultation.

Conclusions: The objective of the study was to undertake a detailed flood study of the Main Drain J catchment and establish models as necessary for design flood level prediction. This included the assessment of inputs to the catchment from Mirrool Creek. In completing the flood study, the following activities were undertaken:,

The study was commissioned by Bayside Council, with the assistance of the NSW Government Office of Environment and Heritage (OEH). Additional information has been provided by Sydney Water Corporation (SWC). The Flood Study comprises the development of computational hydrologic and hydraulic models that define design flood behaviour for the 20% AEP (0.2 EY), 10% AEP, 5% AEP, 1% AEP and 0.5% Annual Exceedance Probability (AEP) design storms and the Probable Maximum Flood (PMF) in the Bardwell Creek and Wolli Creek catchments.

This report describes the hydraulic modelling for the first stage of a flood study of the Hawkesbury-Nepean Valley commissioned by the Water Board in 1987. The study is required in order to "determine the effects that various arrangements of major or future works for Warragamba Dam have on flooding in the valley" (Revised Brief for the Preparation of an E.I.S., Water Boards August 1987). Stage 1 required a simplified model to be developed, calibrated and used to provide a measure of the relative effects on flooding of options for such works. The model used is described in Section 2. Section 3 describes the calibration phase, in which three historical floods were used to adjust model parameters in order to match historical and modelled flood heights. The various options for Warragamba Dam flood protection works have an impact on the outflow hydrographs from the dam. Outflow hydrographs were determined for each option for five "design" floods and run through the calibrated hydraulic model. Peak flood heights were then tabulated and compared at three key locations In the valley. Section 4 describes the options while Section 5 discusses the modelling methods used to run these cases. The results are presented as a series of tables and graphs.

Includes: Main Flood Study Report and Addendum Climate Change Assessment Report and Kallaroo Circuit Culverts Assessment

The investigation process used in this flood study was: - collection of available data; - assessment of available data; - overview of lagoon behaviour; - assessment of coastal processes; - hydrologic modelling of the catchment to determine flood inflows; and - hydraulic modelling of the lagoon to assess flood levels from flood inflows.