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NT Remote Communities Storm Tide Study and Inundation Mapping



NT Remote Communities Storm Tide Study and Inundation Mapping


Systems Engineering Australia Pty Ltd

Issued by

Northern Territory. Department of Land Resource Management


E-Publications; E-Books; PublicationNT; J1507-PR001B




Made available via the Publications (Legal Deposit) Act 2004 (NT).; 'This report documents tropical cyclone (TC) storm tide hazard analyses that will provide the basis for reliable risk analyses of major remote towns and indigenous communities on the West Coast, Arnhem Land and Tiwi Islands.' - Introduction


This Storm Surge Study Report was produced with funding provided by the Northern Territory and Australian Governments through the Natural Disaster Resilience Program. 'Numerical Modelling and Risk Assessment' - on cover.; Made available via the Publications (Legal Deposit) Act 2004 (NT).

Table of contents

Executive summary -- Introduction -- The study localities -- Methodology to assess the storm tide hazard -- Simulation model results -- Conclusion -- References -- List of Appendices A-C.




Storm surges; Storm surges; Cyclones; Maps; Mathematical models

Publisher name

Northern Territory Government

Place of publication





vi, 62, 4,3,8 pages : colour illustrations, colour maps ; 30 cm.

File type



Attribution International 4.0 (CC BY 4.0)

Copyright owner

Northern Territory Government



Parent handle


Citation address


Page content

NT Department of Land Resource Management NT Remote Communities Storm Tide Study and Inundation Mapping J1507-PR001B 4 Systems Engineering Australia Pty Ltd July 2016 Local potential flooding extent and inundation depths are then obtained by comparison with AHD-relative elevation mapping. The localised effects of wave runup may pose specific threats additional to the stillwater storm tide level. For more specific detail on the water level components and dynamics of storm tide the reader is referred to Harper (2001) or SEA (2006). Ocean Waves Wave Setup Extreme Winds Currents Wave Runup HAT AHD datum Expected High Tide Storm Tide Surge Copyright 2014 Systems Engineering Australia Pty Ltd Low Pressure Figure 1-2 Water level components of an extreme storm tide. 1.4.1 Mitigating Effects on Extreme Storm Tide There are a number of factors that can act to mitigate the potential impacts of storm tide. Firstly, the daily astronomical tide range provides a degree of protection against extreme storm tide attack because of the possibility of the TC impacting at the time of lower tide levels. For example, at Darwin the peak tide range is relatively high at approximately 8.2 m (ANTT 2005), which likely exceeds the highest possible storm surge magnitude at this location. The highest expected tide level at any location is termed the Highest Astronomical Tide (HAT) and occurs theoretically once each 18.6 y period, although at many locations tides close to this level can occur annually even without weather-related (e.g. monsoon) enhancement. Considering Darwins very high tidal range means that it is possible, although very unlikely, that the worst possible storm surge event might not even exceed HAT if it were to occur on a very low tide. However, this