8 June 2011 – More than $226 billion of assets in national coastal areas are potentially at risk from climate change, heralding changes to planning regimes and buildings codes in urban environments, a report released by Minister for Climate Change and Energy Efficiency, Greg Combet warns.
The analysis, Climate Change Risks to Coastal Settlements and Industry, which supplements the 2009 Climate Change Risks to Australia’s Coasts report describes the exposure of coastal infrastructure to inundation and erosion.
It identifies important risks to commercial and light industrial infrastructure and road and rail systems in coastal areas based on a sea level rise of 1.1 metres representing a high-end scenario for 2100.
Coastal assets at risk from the combined impact of inundation and erosion include:
• Between 5800 and 8600 commercial buildings with a value ranging from $58 to $81 billion (2008 replacement value);
• Between 3700 and 6200 light industrial buildings with a value of between $4.2 and $6.7 billion (2008 replacement value), and
• Between 27,000 and 35,000 kilometres of roads and rail with a value of between $51 and $67 billion (2008 replacement value).
“Governments at all levels need to be aware of the potential future costs of climate change, particularly as it affects the frequency and intensity of natural disasters, which currently cost around $1 billion per year on average,” Mr Combet said.
The report shows exposure of coastal assets to sea level rise is widespread and will likely increase.
“The science tells us we can avoid the worst of these potential impacts if we reduce our carbon pollution—that is why the government is committed to putting a price on carbon,” Mr Combet said.
“We can also reduce our vulnerability to impacts we can’t avoid by using the best available science to plan timely and cost-effective adaptation measures.”
Mr Combet said adaptation measures would vary depending on location and circumstance, but could include changes to planning regimes and buildings codes in urban environments.
Decisions about future development, particularly in areas highly exposed to the impacts of climate change, should not increase risk.
While the analysis excluded consideration of critical infrastructure such as hospitals, or that involved in the delivery of some essential services such as wastewater systems, it is expected that climate change will impact on the delivery of some of these services.
Other key findings:
• Victoria and WA have the most commercial buildings exposed to a sea level rise of 1.1 metres: 1,500–2,000 buildings at risk in Victoria and 1,500–2,100 in WA.
• Queensland (900–1,400), NSW (700–1,200) and South Australia (900–1,500).
• Replacement values are: South Australia $22–$27 billion, WA $12–$17 billion, Queensland $10–$15 billion, Victoria $8–$12 billion and NSW $5–$9 billion.
Light industrial buildings
• Queensland with 1200–1800 buildings at risk has the most light industrial buildings exposed to this sea level rise.
• NSW (600–1000), Victoria (600–1,000), South Australia (400–1100) and WA (600–900).
• Replacement values: $1.3–$2.0 billion, Queensland; $0.6–$1.2 billion, South Australia; $0.8–$1.1 billion, NSW; $0.7–$1.1 billion, WA and $0.5–$0.8 billion, Victoria.
Risks to transport infrastructure
• Nationally, between 26,000 and 33,000 kilometres of roads are potentially at risk from the combined impacts of inundation and shoreline recession. This figure is made up of 1100–1,500 km of freeway, 10,000–13,000 km of main roads and 15,000–18,000 km of unsealed roads. While most of the risk is to main roads, unsealed roads and tracks, the cost to replace freeway will be higher than replacing the same length of other types of road, and disruption to freeways will have a greater impact on transporting goods and people.
• WA has the greatest length of roadway at risk, with between 7500 and 9100 km exposed, at a replacement value of between $8.7 and $11.3 billion. Much of the exposure is to unsealed roadway.
• Queensland has the greatest value of existing road infrastructure at risk, with between $9.7 and $12.9 billion for between 3600 and 4700 km of roadway. Queensland’s higher value relates to the greater percentage of freeway and main roads at risk in Queensland.
• All states, with the exception of Tasmania and the Northern Territory, have an estimated replacement value of greater than $7 billion.
Rail and tramways
• Nationally, between 1200 and 1500 km of rail lines and tramways are potentially at risk, with a value of between $4.9 and $6.4 billion.
• Queensland has the greatest length (between 420 and 570 km) and highest estimated replacement value (between $1.7 and $2.3 billion) for rail and tramway infrastructure. NSW, South Australia and Tasmania have a replacement value of between $0.6 and $1.3 billion each. Assets exposed in Victoria, WA and the Northern Territory have a replacement value of between $0.1 and $0.5 billion.
Risks to residential buildings
• Queensland and NSW have the most residential buildings with between 44,000 and 68,000 residential buildings at risk in each state.
• Victoria and South Australia (31,000–48,000 in each state), WA (20,000–30,000), and Tasmania (12,000–15,000).
Replacement values: $15–$20 billion, Queensland; $14–$20 billion, NSW; $8–$11 billion, Victoria; $5–$8 billion in each of South Australia and WA and $4 billion, Tasmania.
Projecting risk against a changing population
The Australian Bureau of Statistics has forecast an increase in Australia’s population from 21 million in 2007 to between 30.9 and 42.5 million people by 2056, and to between 33.7 and 62.2 million people by 2101 –based on differing assumptions of fertility, mortality, internal migration and overseas migration.
More recently, the Intergenerational Report 2010 projects that Australia’s population will grow by 65 per cent, to more than 35 million people in 2049.
Based on current trends much of this growth would be accommodated in coastal settlements and cities.
The report says the increase in population has a greater impact on the number of buildings at risk than the increase in sea level.