Climate Change and Infrastructure Planning Ahead

Transcription

1 Climate Change and Infrastructure Planning Ahead

2 Climate Change and Infrastructure Planning Ahead Infrastructure the physical facilities that support our society, such as buildings, roads, railways, ports and airports, dams, water pipes, power stations, electricity transmission, sewerage, communication and drainage systems. Decisions made today for example, in the creation of new infrastructure or other assets need to occur in a way which ensures that the outcomes of those decisions are robust enough to cope with, or adapt to, changing climatic conditions in the future. Victorian Greenhouse Strategy Action Plan Update, Victorian Government, 2005 Australian infrastructure is valued at $1,500 billion (Australian Bureau of Statistics, 2002). A significant portion of this is located in Victoria. Most infrastructure has been built based on historical climate information. But our climate is changing. Since 1910, the planet has warmed by around 0.8 C. Globally, the last 10 years include the warmest years on record. The past 30 years have seen an acceleration in the rate of warming to almost 0.2 C per decade. In Victoria, temperatures are rising and rainfall has declined significantly during the past decade. Around Melbourne, rainfall during the last 10 years has been about 20% below the long-term average, and 10% below that of any other decade in recorded history. Parts of western Victoria have also experienced the lowest recorded rainfall over the last 10 years. Some of the climatic changes we are experiencing are natural; some are being caused by emissions of heat-trapping greenhouse gases, such as carbon dioxide, into the air. Looking to the future, by 2030, average daily maximum temperatures are likely to rise by 0.5 to 1.5 C over most of Victoria, compared to 1990; by 2070, they are likely to rise by 0.7 to 5.0 C. There will be more hot days and fewer cold days, with an associated increase in fire-weather risk. Increases in extreme daily rainfall are likely in many regions. The sea level is projected to rise by 3 to 17 cm by 2030 and 7 to 52 cm by 2070 relative to These are CSIRO assessments, supported by international findings. For further information on climate change and projections for Victoria see

3 The community expects that our cities and infrastructure will cope with severe weather events efficiently and safely. Climate Change Risk and Vulnerability. Report to the Australian Greenhouse Office, Department of the Environment and Heritage, by the Allen Consulting Group, 2005 Infrastructure and climate change Infrastructure represents such a major investment that it is important to build it to cope with future changes. This means that recognition of likely climate change, its impacts and appropriate adaptation measures should occur now. However, most infrastructure has been designed, built and maintained on the premise that the future climate will be similar to that experienced in the past. Recognition of the risks associated with climate change is a valuable first step towards better planning of new infrastructure investments and mitigating potential damage to existing infrastructure. The Victorian Government has commissioned a preliminary examination of the potential risks to infrastructure caused by likely future climate change. The examination relied on the approach determined by the Australian Standard for the identification and assessment of risk. For each climate change variable identified, a worst-case scenario for the years 2030 and 2070 was considered. The assessment is on the basis of no adaptation responses to climate change being undertaken. In developed countries, adaptation will be required to reduce the costs and disruption caused by climate change, particularly from extreme weather events like storms, floods and heatwaves. Adaptation will also help take advantage of any opportunities, such as development of new crops or increased tourism potential. But at higher temperatures, the costs of adaptation will rise sharply and the residual damages remain large. The additional costs of making new infrastructure and buildings more resilient to climate change in OECD countries could range from $ billion each year ( % of GDP), with higher costs possible with the prospect of higher temperatures in the future. Stern Review: The Economics of Climate Change, Cabinet Office, HM Treasury, UK 2006 The following infrastructure categories were examined: Storage reservoirs, waterways and irrigation channels; reticulated sewage systems, trunk sewers and treatment plants; and stormwater drains and land prone to flooding. Power Electrical power generation and transmission to substations; gas and oil extraction, refining and distribution networks. Fixed line networks, including trunk lines to exchanges; and mobile network transmission towers. Roads, railway lines, tunnels, bridges, airports, ports, including jetties, piers and seawall protection. Buildings All residential, commercial, industrial buildings and storage structures; parks, community and public space facilities. Climate change variables considered included: > Extreme maximum temperature, and length of hot spells > Annual rainfall > Extreme daily rainfall, influencing flood levels > Available moisture, which is influenced by changes to evaporation rates and levels of rainfall > Annual average relative humidity > Variation in wet and dry spells, affecting water tables and surface and subsoil inundation cycles > Intensity of extreme winds > Fire-weather frequency and intensity > Solar radiation levels and exposure > Sea level rise Climate change exposure and infrastructure sensitivity Table 1 presents information on the likely risk of impacts of climate change on various types of infrastructure. Sewerage systems, for example, would not be affected by greater solar radiation, but may be impacted by drier soil. Table Legend Negligible Risk Definite Risk Sectors most at risk Risk to each infrastructure sector was assessed as low, moderate, high or extreme for low and high climate change scenarios for the years 2030 and Low climate change scenario, 2030 The water sector is the only studied infrastructure sector at significant risk from climate change impacts associated with a low climate change scenario for the year 2030 (See Table 2). (The low scenario represents the minimum level of likely changes projected by researchers.) High climate change scenario, 2030 The water, power, telecommunications, transport and buildings sectors are all at significant risk from climate change impacts, as indicated in Table 3. No extreme risks were identified for this scenario. Low climate change scenario, 2070 All infrastructure sectors are exposed to a high level of potential risks. However the water sector is considered to be at extreme risk. The 2070 low scenario is very similar to the 2030 high scenario, except for greater potential increases in extreme rainfall events in 2070 compared to 2030 (resulting in greater storm water flooding damage to drainage infrastructure, bridges and tunnels). High climate change scenario, 2070 This scenario represents a considerable increase in the extent of climate change and, hence, potential impacts on Victoria s infrastructure. The water, power, transport and buildings sectors all have high and extreme risks, while telecommunications has high risks, as indicated in Table 4. Table 1: Climate change exposure and infrastructure sensitivity Climate Change Impacts Infrastructure Type Increased Solar Radiation Decrease in Available Moisture Increased Variation in Wet/Dry Spells Increased Temperature & Heatwaves Table 2. Risks associated with the low climate change scenario for the year 2030 Sector High risks shortages Decrease in Rainfall Increase in Extreme Daily Rainfall Increase in Frequency & Intensity of Storms Table 3: Risks associated with the high climate change scenario for the year 2030 Sector Power Buildings Sewer Stormwater Electricity Gas and Oil Fixed Line Telecom Network Mobile Network Roads Rail Bridges Tunnels Airports Ports Buildings and Structures Urban Facilities High risks shortages Bushfire damage to catchments and storage Increase in demand-pressure shortages Substation flooding Flooding of exchanges, access holes and underground pits Bridge degradation Increase in Intensity of Extreme Wind Storm impacts on ports and coastal infrastructure Degradation and failure of foundations due to changes in soil moisture Increased storm and flood damage Coastal storm surges and flooding Increased bushfire damage Increased Electrical Storm Activity Increase in Bush Fires Sea Level Rise Humidity

4 In designing buildings and communities, it is important to plan for the climate throughout the design life of the development, not just for the current climate. Adapting to Climate Change: A Checklist for Development, Three Regions Climate Change Group, UK, Table 4: Risks associated with the high climate change scenario for the year 2070 Sector High risks Extreme risks Degradation and failure of water supply piping shortages Degradation and failure of sewer piping Bushfire damage to catchment and storage Sewer spills to rivers and bays Degradation and failure of drainage infrastructure Power Storm damage to above-ground transmission Increase in demand pressure shortages Substation flooding Reduction in hydroelectricity generation Reduction of coal electricity generation Offshore infrastructure storm damage Storm damage to above-ground transmission Nil Flooding of exchanges and underground pits, access holes and networks Road foundations degradation Storm impacts on ports and coastal infrastructure Rail track movement Bridge structural material degradation Storm damage to bridges Tunnel flooding Sea level rise impacts on tunnels near the coast Extreme event impacts to airport operations Sea level rise impacts on port infrastructure materials Buildings Degradation and failure of foundations Increased storm and flood damage Degradation and failure of materials Coastal storm surge and flooding Increased storm and flood damage to urban facilities Increased bushfire damage Coastal storm surge and flooding to urban facilities Climate change impacts on infrastructure sectors There is a growing understanding of the potential impacts of climate change on infrastructure, but more detailed assessments will be required to develop adaptation responses. A summary of the range of potential climate change impacts for each assessed infrastructure sector is presented below. > Climate change is likely to result in drier conditions for most regions. However, extreme rainfall events are likely to increase in frequency and intensity. > An increasing frequency of extreme daily rainfall events would affect the capacity and maintenance of storm water, drainage and sewer infrastructure. Significant damage costs and environmental spills are likely if these water systems are unable to cope with major downpours. > Increased risk of major bushfires in the catchments of dams and reservoirs will threaten water quality and availability. > Due to drier conditions, increased ground movement and changes in groundwater could accelerate degradation of materials and structural integrity of water supply, sewer and stormwater pipelines. > Lower rainfall is likely to lead to water shortages, exacerbated by higher temperatures and increased demand from a growing population. Energy > Increased frequency and intensity of extreme storm events may damage electricity transmission infrastructure and service. Increased wind and lightning could also damage transmission lines and structures. Extreme rainfall events could flood power substations. More storm activity would increase the cost of power and infrastructure maintenance and lead to more, and longer, blackouts and disruption of services. > Coastal and offshore gas, oil and electricity infrastructure is at risk of significant damage and increased shut-down periods from increases in storm surge, wind, flooding and wave events. Sea level rise would worsen these impacts. > Increased ground movement and changes in groundwater are likely to accelerate degradation of power generation and refinery plant foundations, as well as of transmission lines, gas and oil pipelines. > Extreme heatwave events are likely to increase in frequency, generating an increase in the peak demand for electricity for air conditioning. > The anticipated decrease in annual rainfall may reduce the power supply capacity of hydroelectric dams and the water supply necessary for cooling of coal-fired power stations for power generation. > Increased frequency and intensity of extreme wind, lightning and bushfires may cause significant damage to above-ground transmission lines and associated infrastructure. > Downpours will affect access holes, pits and other underground telecommunications facilities. > Increased storm activity may result in a significant rise in the cost of telecommunications supply and infrastructure maintenance associated with increased frequency and length of network outages and disruption of communication services. > Increased frequency and severity of extreme rainfall events may cause significant flood damage to road, rail, bridge, airport, port and, especially, tunnel infrastructure. Rail, bridges, airports and ports are susceptible to extreme winds. Ports and coastal infrastructure are particularly at risk from storm surges; sea level rise will add to the problem. > A rise in the frequency of lightning strikes would affect rail operations. The projected increase in storm activity may increase the cost of transport infrastructure maintenance and replacement. > Increased ground movement and changes in groundwater would accelerate degradation of materials, structures and foundations of transport infrastructure. The result would be reduction in life expectancy, increased maintenance costs and potential structural failure during extreme events. > Increased temperature and solar radiation could reduce the life of asphalt on road surfaces and airport tarmacs. Higher temperatures may stress steel in bridges and rail tracks through expansion and increased movement. > Sea level rise may affect tunnels close to the coast through increased tidal and salt gradients, ground water pressure and corrosion of materials. Building > Buildings will be affected by increased frequency and intensity of extreme rainfall, wind and lightning. Coastal buildings and facilities will be particularly at risk from storm surges exacerbated by higher sea levels. The predicted increase in storm activity could raise the cost of public and private building maintenance and replacement. > Increases in bushfire frequency and intensity have the potential to increase rates of damage to buildings and structures, especially those in non-urban areas. > Drier conditions may lead to increased ground movement and changes in groundwater. Higher temperatures and more solar radiation could amplify degradation of materials.

5 Authorised by the Victorian Government, Melbourne. Printed by TYPO, Tope St, South Melbourne 3205 State of Victoria, Department of Sustainability and Environment 2006 ISBN: This publication may be of assistance to you but the State of Victoria and its employees do not guarantee that the publication is without flaws of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication. This publication is copyright. No part may be reproduced by any process except in accordance with the provisions of the Copyright Act The information and photography contained in this booklet were produced by CSIRO (Atmospheric Research) on behalf of the Victorian Government.