AusGeo News June 2005 Issue no. 78
New results on natural hazards in Perth
A major assessment of natural hazard risk for the Western Australian (WA)
capital has been completed by Geoscience Australia in partnership with federal,
state and local agencies.
Cities Project Perth provides authoritative new knowledge on the risks from
the sudden onset of natural disasters in Australia’s fourth largest
Perth’s major hazards
The study area covered greater metropolitan Perth (figure 1). Major natural hazards
considered in the project included:
- flood hazard in the Swan River and its tributaries
- severe wind hazard in metropolitan Perth
- earthquake risk in metropolitan Perth and the earthquake hazard in the
wheatbelt up to 200 kilometres from Perth
- the susceptibility of the southwest coastline, including Perth beach
suburbs, to sea level rise from climate change
- potential tsunami impacts on the coastline
The project also investigated socioeconomic factors that might affect the
capacity of Perth citizens to recover from natural disasters, and compared
WA with other Australian states.
Work included the preparation of more than a dozen major spatial databases
and risk assessment models, including the flood hazard model and comprehensive
building and building footprint databases, digital elevation models and GIS
Figure 1. The study areas for Cities Project
image [GIF 86Kb])
- Cool season storms and tropical cyclones that move southwards, often
with associated bushfires, have caused southwest WA’s highest natural
hazard insurance losses in the past. Cities Project Perth found that communities
with high exposure to wind, such as coastal communities, face a measurably
higher wind hazard than current building codes describe.
- More wheatbelt communities have been included in an enlarged earthquake
source zone east of Perth, rating them at higher hazard than described
in the current earthquake loadings standard.
- Potential losses from earthquakes are considerably higher than estimates
of historical costs of earthquakes in WA.
- Eight flood scenarios have been modelled for the Swan River, with annual
exceedance probabilities ranging from 0.05% to 10%.
- As the Perth metropolitan area has a high number of households with
relatively high economic resources, a large majority of households in the
area would be able to draw on their own economic resources to assist recovery
after a natural disaster. However, households in some areas could find
the recovery process hard because of limited financial capacity.
- WA’s strong community network will be a positive source of support
in managing recovery from natural disasters.
Many WA and local government agencies participated in the four-year project.
They continue to play a key role as custodians of the project’s models
and data and by implementing policy and practice based on the results. Our
core partners were the WA Fire and Emergency Services Authority, the WA Department
for Planning and Infrastructure, the WA Department of Environment, and the
Bureau of Meteorology’s WA Regional Office.
The Cities Project Perth report was launched in Perth on 8 June by
Parliamentary Secretary Warren Entsch, and a half-day workshop for local
and regional emergency managers and other stakeholders was held to discuss
the results and their implications for Perth.
The report can be ordered from www.ga.gov.au/sales.
The full report will be also available for download on the Geoscience Australia
For further information: phone Trevor Jones on +61 2 6249
9559 or email email@example.com