Climate Change Risk Assessment
2015
vicroads.vic.gov.au Disclaimer This Assessment document has been prepared by VicRoads to assist it in adapting to climate change in the construction, maintenance and management of road and road related assets. While it has been prepared taking all professional care, it should not be relied on as the basis of decision making, but could contribute to the strategic context to inform further work. Contents Executive Summary 4 1. Introduction 5 2. Climate Change Adaptation 6 3. Strategic Context 8 4. Climate Change Projections 11 5. Climate Change Risk Assessment 14 5.1 Asset information 17 6. Detailed Risk Assessment 20 6.1 Sea Level Risk 20 6.2 Temperature 24 6.3 Rainfall 25 6.4 Extreme Weather Events 28 6.5 UV Level 29 6.6 Prioritising Risks 30 7. Developing Adaptation Responses 32 7.1 Sea Level Rise 32 7.2 Temperature 34 7.3 Rainfall 35 7.4 UV Level 36 7.5 Long Term Asset Responses 36 7.6 Organisational Responses 37 8. Next Steps 38 Glossary 39 Bibliography 40 Appendices 42 Appendix 1 : Case Studies 42 Phillip Island Road – Climate Adaptation 42 Great Ocean Road – Adaptation Measure 43 Executive Summary Overall, the climate change risk assessment has identified that whilst there are forecast impacts to Similar to other road agencies both nationally and different asset classes through time, the appropriate internationally, VicRoads is working to develop approach is primarily guided by the likely lifespan its own responses to climate change. Significant of the assets. For example, with respect to assets effort has been undertaken in the last five years with short life spans (i.e. Intelligent Transport to understand the level of risks posed to the road Systems), or periodic replacement requirements network from the projected changes in climate and (i.e. pavement surfacing) adaptation measures to take action to mitigate its greenhouse emissions will be implemented as a running change at an to lessen the impacts and the risks associated with appropriate point in time. However, a number of climate change (VicRoads, 2010). assets have a lifetime beyond normal budgetary In general the more mitigation there is, the less forecasting timeframes (i.e. bridges). In these cases, will be the impacts to which we will have to adjust the adaptation measures will need to be built into and the less the risks for which we will have to try the construction requirements of future assets and prepare. Conversely, the greater the degree of and a set of responses will be needed to manage preparatory adaptation, the less may be the impacts existing assets to ensure they continue to perform associated with any given degree of climate change. for their planned life. This risk assessment document summarises the The greatest single climate change risk to VicRoads work undertaken to assess the risks to VicRoads is the impact to assets in coastal regions from sea infrastructure associated with climate change level rise. Whilst these impacts are predicted in low parameters, as well as some appreciation of the lying areas across the entire Victorian coastline, timeframe and potential directions for climate change the impact is likely to be greatest in Eastern adaptation. In developing this Assessment document, Region, potentially through a combination of the VicRoads has assumed a future climate with the overtopping of roads, impacts to pavement layers highest level of climate change impact, consistent and the structures of bridges in these locations with the approach of most organisations and resulting in likely interruptions to network operations. government bodies within Australia. Whilst it is important to start building knowledge in the shorter term to support adaptation actions, sufficient time remains to be better informed as new information emerges regarding climate projections. As a consequence, this adaptation strategy will need to continuously evolve as more modelling and measurement is undertaken to monitor the performance of the road network over time. This is particularly important as data regarding the performance of the road network or changes to climate projections will be analysed and absorbed often faster than policy and planning can adapt.
4 1. Introduction Many of the projected impacts will be adverse, but some may be positive. This Assessment The VicRoads road network is a $45 billion document outlines how VicRoads will address government asset, a key component of the state’s adaptation in response to the potential impacts overall transportation infrastructure, which links of climate change during the planning, design, with local roads and other transportation modes. operation and maintenance of the State’s main Its continued safe and efficient operation is road infrastructure. In particular, it addresses essential to economic prosperity. how VicRoads will factor in anticipated changes VicRoads operates, maintains and upgrades the in climatic parameters into the delivery of its main and arterial road network, which consists of activities and develop appropriate management over 22,500 kilometres (51,500 lane kilometres) of and mitigation solutions to remove or reduce main roads across the state. Approximately 19,100 these risks. kilometres are located in regional Victoria, the The magnitude and rate of climate change remainder in Metropolitan areas. Many of VicRoads depends partly on future global greenhouse activities are either directly affected or influenced emissions. Consequently, mitigation action to by the weather and climate. Along with other state reduce greenhouse gas emissions has been and and national infrastructures, roads are vulnerable to continues to be a key focus of other strategies. the effects of climate change. However, even if global greenhouse gas emissions were to stop today, climate change would continue for many decades as a result of past emissions and the inertia of the climate system. Adaptation to already experienced changes in climate as well as to plausible future climate scenarios is therefore a necessity.
CLIMATE CHANGE RISK ASSESSMENT 5 2. Climate Change Adaptation Second, the result of adaptive action either decreases a system’s vulnerability to changed There is increasing scientific consensus that the conditions or increases its resilience to negative global climate is changing, with these changes impacts. For example, increasing ultra-violet being observed and increasingly documented radiation exposure can cause bituminous surfaces across the world (Stocker, et al., 2013), across across the road network to fail sooner than Australia (CSIRO, 2014), across Victoria anticipated. Using different materials or different (Commissioner for Environmental Sustainability approaches that recognize this vulnerability can Victoria, 2012) and locally within Victoria (SKM, lead to surfaces pavement that will not suffer 2012). These changes are relative to historical adverse performance with higher radiation levels. trends and are being observed in a number of climate parameters such as rainfall volumes and Operational improvements could be made to patterns, temperatures as well as sea levels. Whilst enhance detour routes around flood-prone areas as most parameters are currently operating within a form of resilience. Another example of resilience historical ranges, they are forecast to move beyond is the development of well-designed emergency these by the end of the current century. response plans, which can increase resilience by quickly providing information and travel alternatives A number of organisations have sought to define when highway facilities are closed and by the concept of adaptation. For the purposes of facilitating rapid restoration of damaged facilities. this Assessment document, adaptation consists By increasing system resilience, even though a of actions that reduce the vulnerability of natural particular facility might be disrupted, the main road and human systems or to increase system network as a whole still functions and decreases resiliency in light of expected climate change the consequences of impacts. or extreme weather events. Climate change adaptation for VicRoads is concerned with Figure 2.1 illustrates the different approaches to maintaining network and asset performance adaptation. Some adaptation strategies could be within this changing climate. Several aspects targeted to reduce the impacts of specific types of this definition merit attention. of climate changes. For example, by protecting existing assets or by relocating assets away from First, the types of actions that can be taken to reduce vulnerable areas, the functionality of that asset vulnerability to changing environmental conditions is preserved in future years when more extreme include avoiding, withstanding, and/or taking weather events could create a threat. advantage of climate variability and impacts. Thus, for roads and other road related facilities, avoiding Ultimately, a wide range of activities will be areas forecast to have a higher risk of significant considered “adaptation,” from relatively simple climate impacts should be an important factor in operations and maintenance actions such as planning decisions. If such locations cannot be ensuring culverts and stormwater drains are avoided, steps need to be taken to ensure that road clear of debris, to complex and costly planning infrastructure can withstand the projected changes and engineering actions like re-locating a road in environmental conditions. For example, the alignment away from an area prone to erosion or potential for increased flooding might be a reason to sea level rise. Given the broad scope of adaptation increase bridge elevations beyond what historic data activities, it is important that a comprehensive might suggest. Climate change may also present decision making approach be formulated that opportunities that transportation professionals can describes the steps engineers, planners, operations take advantage of, like the placement of bituminous and maintenance personnel, should take to focus surfacing during spring and autumn at some on the significant risks on the transport system as a locations. These types of actions decrease the whole and avoid piecemeal decision making. Such likelihood of impacts occurring. an approach should also be sufficiently flexible to allow for the consideration of updated climate change forecasts as well as an examination of a range of potential cost-effective solutions.
6 Figure 2.1 Illustration of How Activities to Decrease Likelihood and Consequence Fit Together and Influence the Impacts and Consequence of Climate Change.(Adapted from (Melillo, Richmond, & Yohe, 2014)
CLIMATE CHANGE RISK ASSESSMENT 7 3. Strategic Context From a planning perspective, the risks associated with climate change was added to the Victorian Planning Understanding our community and customers Provisions in 2012 (Victorian Planning Provisions needs and the different adaptation strategies that Section 10 Clause 13) to take into consideration the may be adopted by various transport stakeholders potential for a 0.8m sea level rise by 2100 and an will be key to ensuring a well functioning transport additional 0.2m allowance for a 1 in 100 year flood by system as the backbone for economic activities 2040 for urban infill developments. and movement of people. In recognising the importance of climate change At this stage, the only legislative requirement and adaptation as both a strategic and operational in relation to climate change adaptation is the risk, VicRoads has integrated climate change Victorian Climate Change Act 2010 which requires impacts into its existing corporate risk management the Victorian Government to develop a Climate framework. This framework has been used as the Change Adaptation Plan every four years to outline basis for determining the significance of climate the potential impacts and risks associated with a change risk to VicRoads assets, using the following changing climate. The first Victorian Climate Change risk categories: Adaptation Plan was released in March 2013 (DSE, 2013) which lists the key risk to roads as being; zz Business performance and capability zz Financial
More frequent extreme weather events may zz Assets increase the risk of disruptions to traffic, zz Management effort and people increase maintenance and repair costs and replacement of pavements and structures zz Environmental and cultural heritage (bridges and culverts). zz Legal and compliance
zz Occupational health and safety In response to this risk, the VicRoads Sustainability Having identified the risk assessment criteria, this and Climate Change Strategy 2010-2015 was information was then utilised to assess climate referenced as the Victorian Government response risks and to document the systematic process for managing risks to roads. However, this undertaken to determine the need for adaptation Assessment document was largely focused on responses and how these will be incorporated into mitigation measures and while mitigation tackles subsequent policies and procedures for planning, the causes of climate change, adaptation tackles maintenance or operational personnel. The the effects of the phenomenon. Climate mitigation systematic approach is outlined in Figure 3.1. and adaptation should not be seen as alternatives to each other, as they are not discrete activities but rather a combined set of actions in an overall approach to reduce greenhouse gas emissions. It has since been recognised that a more detailed approach was required to address the interagency and statewide risks presented by climate change (VAGO, 2013).
8 lder Eng keho agem Sta ent Determine risk assessment criteria and assumptions
Review
Establish relevant Develop adaptation climate change responses and projections implement as planned
Research, monitoring or periodic review
Prioritising risks based Establish asset on asset life and type categories adaptation window
Determine susceptible assets and activities (RIsks)
Figure 3.1 VicRoads Climate Adaptation Framework
CLIMATE CHANGE RISK ASSESSMENT 9 In addition, the VicRoads Strategic Commitment 2015-2019 has identified four key strategic objectives each of which can be adversely impacted by climate risk. These are described in more detail in Table 3.1.
Table 3.1 Relationship between VicRoads Strategic Commitment and Climate Change Impacts.
Strategic Commitment Climate Change Impacts by 2070 Customers & Community VicRoads recognises the value of engaging with the community to understand their needs, so climate adaptation responses We create solutions with our Customers developed will provide the better solutions. and Community
Journeys Whilst decreased rainfall and increased temperatures will overall be a positive influence on travel time predictability, it Enabling integrated transport choices and making is recognised that adverse weather events will create stressful journeys pleasant and predictable conditions. Impacts to vegetation may also have an adverse impact on the amenity of road users.
Wellbeing Increased temperatures will have a positive impact on risks from black ice and snow. However, in some specific circumstances Improving road safety, amenity and environmental there may be temporary increases to aquaplaning risks during outcomes more intense rain events.
Productivity There are likely to be increased maintenance requirements to assets with long design lives or those which are difficult Strengthening the economy through better use to adapt, which may impact on the productivity of the road of roads and connections with land use network. Adverse weather events are also likely to impact on the productivity of the road network
VicRoads interactive website is an example of a tool to address customer needs for greater and more timely information regarding network performance and availability as a result of adverse weather events.
10 4. Climate Change Projections For the purposes of assessing risk to the road network, the 2070 projections have been adopted Climate change projections for 2030, 2070 as the most appropriate basis to guide the and 2100 have been adopted based on the development of this Assessment document for Intergovernmental Panel on Climate Change the following reasons: Fourth Assessment Report (IPCC AR4)1 (Solomon, et al., 2007). There are a range of future climate zz The incremental climate change projections at scenarios within the IPCC AR4 projections and 2030 generally produce effects that are within these are shown Figure 4.1. The scenarios are historical operating conditions and would not require any special actions. The 2030 projections based on the following assumptions: were therefore considered as not suitable as zz A1: Rapid economic growth, global population an indicator of possible future actions for an that peaks in mid-century and declines adaptive response. thereafter followed by rapid introductions zz Many of the 2100 model projections diverge of new and more efficient technologies quite widely due to the large degree of zz A2: A very heterogeneous world with an uncertainty. In addition, it was considered that emphasis on family values and local future changes to other factors affecting road traditions asset management such as the split of transport modes, land use, travel patterns etc would also zz B1: Introduction of clean technologies be a critical input to adaptive responses. zz B2: Emphasis on local solutions to economic zz 2100 projections were seen to be useful for and environmental sustainability reference, but they were not suitable for the The major underlying themes of the A1 scenarios development of specific adaptive responses at are convergence among regions, capacity building, this point in time. Nonetheless, it is recognised and increased cultural and social interactions, with that climate change impacts are forecast up to a substantial reduction in regional differences in and beyond this time. per capita income. The A1 scenario develops into Exceptions to this approach were: three groups that describe alternative directions of technological change in the energy system. zz consideration of the effects of sea level rise, for The three A1 groups are distinguished by their which there is already a general consensus within technological emphasis: fossil intensive (A1FI), non- state and federal government departments on fossil energy sources (A1T), or a balance across all the appropriate amount of sea level rise to adopt sources (A1B). for the year 2100 (Victorian Planning Provisions Section 10 Clause 13, 2014). VicRoads has adopted the A1FI future climate scenario, which is based on the continuation of a zz Where the only data available for a climatic fossil intensive energy sector with the generation parameter is based on 2100 projections, such as of greenhouse gases projected to increase the increased incidence of warm nights over 21°C. accordingly. This is a conservative worst case position projecting the more significant impacts of climate change. This is consistent with the approach to climate change accepted elsewhere within Victoria (SKM, 2012) (CSIRO, 2007 e) and Australia (DCCEE, 2011). It is also consistent with fossil fuel emissions data which indicate that global emissions are still tracking at or above the A1FI scenario (Global Carbon Project, 2014).
1 The latest data released in IPCC AR5 shows minor changes from the IPCC AR4 report, but indicates a higher level of certainty regarding the potential impacts of climate change (Stocker, et al., 2013). The latest predictions for temperature increases are 2.6 to 4.8 °C by 2100, which has changed from 2.4 to 6.4 °C in the IPCC AR4 report. Projections for sea level rise also remain fairly consistent however, these are still to be reflected in Australian and Victorian projections and models.
CLIMATE CHANGE RISK ASSESSMENT 11 10 Observed 9.5 IPCC projected emissions A1FI A1B A2 B1 B2 A1T 9
8.5
8 Observed emissions have outpaced all of 7.5 the IPCC projections for mid 2010
7 9.14 GtC/y
6.5
6 6.75 GtC/y 6.35 GtC/y Fossil fuel emmissions (Gigatonnes Carbon/year) Fossil fuel emmissions (Gigatonnes 5.5
Mid Mid Mid 5 1990 2000 2010 1995 2015 1990 2010 2005 2000
Figure 4.1 Range of Climate Change Scenarios (Commissioner for Environmental Sustainability Victoria, 2012 - Global Carbon Project)
Currently, Australian data sources such as the a drier climate, the 90th percentile represents a Climate Change in Australia website (CSIRO, wetter climate. A summary of these projections 2007 a) and local projections such as the Future is presented in Table 4.1. Where available, these Coasts Program (DEPI a, 2013) have not yet been scenarios produce relatively consistent projections republished to reflect the IPCC AR5 projections of climate change effects for 2070. and as such they still represent the best level Given that climate change impacts are based on of publically available data. Data has also been modelling, the magnitude of these changes and sourced from other locations where necessary. the certainty of these predictions are represented There is uncertainty inherent in predicting as a range of possibilities, diverging towards the climate change. Where available, scenarios with end of the century and beyond. Sea level rise is an a range of projections represented as percentiles example of this and is virtually certain to extend have been used to gain confidence in the beyond 2100 (Stocker, et al., 2013). projections, however, there were not available A variety of climatic parameters were considered for all parameters. In the vast majority of climate during the development of this Assessment change parameters with percentiles reviewed, document with those seen as relevant to the the percentiles show a clear trend in the one road network shown in Table 4.1. A more detailed direction (e.g. all temperature projections are for description of these climatic parameters are shown a warmer climate). However, in the case of rainfall in Sections 6.1 to 6.5. it shows that whilst the 10th percentile represents
12 Table 4.1 Summary of Projections of Climatic Parameters used in assessing VicRoads Climate Change Risks
2009* 2030 2070 2100** Sea level rise Sea Level Rise 0 +0.15 m^ +0.47 m +0.82 m Storm Surge (Storm Height Return Levels) 1.0 to 2.2 m 1.2 to 2.3 m 1.6 to 2.7 m Temperature Average Annual Temperature (°C) 0 10th percentile +0.3 to 1.0 +1.5 to 2.5 50th percentile +0.6 to 1.0 +2.0 to 4.0 90th percentile +1.5 to 2 +3 to 5°C The frequency of very hot days 9 (32) days 12# (39) days 20 (60) days over 35°C Melbourne (Mildura) The incidence of heatwaves 1 1 1 to 2 (>5 consecutive days over 35°C) The incidence of warm nights over 21°C 0 - - +15-50% Humidity levels (% Change) 0 10th percentile -0.5 to 0.5 -0.5 to 0.0 50th percentile -1.0 to 0.5 -2.0 to -0.5 90th percentile -2.0 to -0.5 - >4 to -1 %
Rainfall Annual rainfall volume 0 - 10th percentile -10 to -20% -20 to -40% 50th percentile -0.2 to +0.5% -10 to -20% 90th percentile -2 to +5% -5 to +40%
Heavy Rainfall Intensity (99th percentile) 0 +1% +6.5% - Number of Rainy Days (>1 mm rainfall) 0 -5% -17% - Evapotranspiration levels 0 +4 to 8% +12 to >16 % - Fire risk The Projected Number of high and extreme 14.8 (56.6) 15.7 to 18.6 # 16.2 to 23.6 ## - fire risk days in Melbourne (Mildura) (59.5 to 66.9) # (62.3 to 90.5) ##
Wind speed 10 metres above ground 0 - 10th percentile +2 to 5% +10 to 15% 50th percentile -2 to +2% -5 to +2% 90th percentile -15 to -5% >-15 to -10% Radiation Radiation levels. Estimated 0 [6.5] - [Annual Average Noon UV Index (x 25 mWm-2)] 10th percentile +1% [6.6] +1% [6.6] 50th percentile +1% [6.6] +5% [6.8] 90th percentile +2% [6.6] +10% [7.2]
*2009 in reality is a twenty year average from 1990-2010, used mostly as a baseline reference ^ sea level rise data point is for 2040. ** 2100 is included in the table for sea level rise and the incidence of warm nights where no earlier projections are available # data point is for 2020 ## data point is for 2050
CLIMATE CHANGE RISK ASSESSMENT 13 5. Climate Change In the case of these recently experienced weather occurrences, they are typical of conditions Risk Assessment elsewhere in the world or indeed in Australia. Over the past five years Victoria has experienced a Under climate change projections, they are also number of occurrences of abnormal weather, which, likely to be reflective of conditions experienced in a number of cases, are similar to or worse than the more frequently in Victoria. It is also recognised projected future climatic parameters, including; that VicRoads has historically experienced weather related road network interruptions such as storm zz the Millennium drought from 1995 to 2009, surges, black ice, snow, storm surge or localised resulting in significantly drier conditions across flooding. This highlights specific susceptible the state and degraded vegetation; locations that will be monitored for any changes in zz seven of the ten hottest years on record have frequency or severity of interruptions. occurred since 1998; An analysis of weather related road closures zz the 2011 floods which impacted a significant between December 2011 and May 2014 portion of the state and resulted in the closure is presented in Figure 5.1 and Figure 5.2 of some regional roads for significant periods demonstrating that road closures are related of time to clear landslides and rebuild roads primarily to rainfall and flooding. and bridges;. Given the number of assets, size and the zz the high temperature conditions experienced geographic diversity of Victoria, the number of in Victoria in 2009, with the hottest day ever occurrences of abnormal weather events as well recorded at 45.8 oC which is even higher than as the projected climate changes, it is necessary the long range projections; for VicRoads to have a sound basis for determining risk, what adaptation should occur and when it zz the record heatwave temperatures of January should occur, in order to address these risks. 2014 with four days in a row of over 40oC, which resulted in several road closures for softened pavements and contributed to pavement surface tearing on the Westgate Bridge; and,
zz the significant bushfires experienced in 2009 with the Black Saturday fires resulting in 173 fatalities and burned over 450,000 hectares including VicRoads roadside assets as well as other infrastructure.
14 Flood damage 3% Temperature (Fire and soft pavement) 6%
Landslip Water on road 8% 70%
Winter weather (snow and ice on road) 13%
Figure 5.1 Road Closures Related to Climate Parameters
Landslip Storm event 3% 1% Snow 3%
Fire 14%
Floodwater 51%
Flood damage 28%
Figure 5.2 Road Hazards Related to Climate Parameters
CLIMATE CHANGE RISK ASSESSMENT 15 Whilst past experience is valuable as a predictor At this point in time, VicRoads along with other of future climate and weather it may not be road agencies in Australia is involved in the sufficient. As noted above, weather conditions and development, modification and adoption of road specifically extreme weather events are already design standards and guidelines. The drainage a primary cause of disruption and road agencies section of the Austroads Guide to Road Design such as VicRoads already dedicate resources to (ARRB, 2013), already includes sections on climate anticipate their impacts and adapt infrastructure change, in particular how rainfall intensity will and operations. However, due to the projected change across catchments and work is underway magnitude of climate change and taking into to review the Australian Standard for Bridge Design account the degree of uncertainty, an incremental (AS 5100), specifically requiring consideration of approach based on traditional practice is not climate change impacts in future design. expected to be effective in the future. Therefore, innovative and broader approaches to adaptation are needed potentially leading to structural changes …. consideration of sustainability and climate in transport services and strengthened cooperation change ensure that these important aspects with other sectors (EEA, 2014). will be incorporated into designs and reduce the risk of occupational health and safety issues and level of service issues of the structures we design (Powers & Rapattoni, 2014).
16 5.1 Asset information VicRoads categorises its assets broadly into seven categories with each having a number of subcategories. These have been used to assess risks within the framework, as described in Table 5.1.
Table 5.1 Description of VicRoads Asset Categories
Asset Type Description Subcategories Road Pavements Road Pavement Layers are made up of compacted layers of structural Concrete Road fill and crushed rock. The purpose of the road pavement is to carry and Asphalt Road distribute wheel loads without deforming and causing damage to the Spray Seal Road surface layers. Unsealed Road Road Surfacing The purpose of the road surfacing is to provide a low maintenance all- Concrete Road Layers weather riding surface, which protects the underlying structural road Asphalt Road pavement from ingress of free water. Water weakens the unbound Spray Seal Road material, causing potholes, ruts and corrugations. Unsealed Road Drainage The surfaces of the 22,500 kilometres of main roads are designed to Surface Flow shed water off the pavement and to ensure safe travel for vehicles Underground Drains during rainfall events. In urban areas, the concentrated flows are Special Drainage Structures collected in concrete channels adjacent to kerbing which lead to underground pipe systems. In most of the rural areas, the concentrated flows are collected in earth lined open drains that carry the collected water to local streams and channels. Roadsides VicRoads manages about 80,000 hectares of road reservation and has Naturally Landscaped Areas planted more than 8 million trees and shrubs. These road reserves also Planted and Landscaped contain significant tracts of landscaped and remnant native vegetation. Areas Roadsides also provide areas for placement of signs and safety barriers, Grassed Areas for landscaping and amenity, footpaths and bicycle paths, visual Natural Slopes screening, as well areas for the safe recovery for errant vehicles. They Paved Areas are also an important location for public utilities such as power, gas, Road Signs and telecommunication cables. Fauna Sensitive Features Pavement Markings Safety Barriers Property Fences Structures VicRoads manages around 3200 bridges on the main road network Road Bridge and more than 4500 other structures such as large culverts, steel Bridge over Waterway gantries and cantilever sign supports, retaining walls and noise barriers. Large Culvert Major Sign Support Noise Walls Retaining Walls and Structural Safety Barriers High Mast Lighting ITS/Electrical Assets There are around 3500 sets of traffic signals on the main road network. Electrical (i.e. street lighting, In addition, there are around 4400 on-road electrical devices such as pits and cables) illuminated or dynamic road signs, CCTV monitoring cameras, help Electronic (i.e. solar phones and various vehicle detection and warning systems, and 70000 installations, height detection street lights (around 90% of these have shared responsibility with local devices) councils). Mechanical (i.e. pumps) VicRoads Activities VicRoads manages a construction and maintenance program to value Planning and Design of around $1.5 Billion per annum including 22,500 kilometres of road Construction and assets valued at over $45 billion. Maintenance Operations
CLIMATE CHANGE RISK ASSESSMENT 17 For each of these asset categories an assessment As part of the subsequent risk analysis, has been undertaken to identify those susceptible consideration was given to the asset life. Each assets and activities which are likely to be negatively asset within VicRoads has a designed or expected affected by climate change. For risk identification, a life which varies greatly depending on the type of combination of the following techniques was used asset. For example electrical Intelligent Transport System (ITS) assets have a design life of ten year or zz Brainstorming outcomes based on facilitated less, whereas some structural assets have a design workshop life of 100 years or more. Figure 5.1 shows the zz Adapted Delphi technique – where risks and range of design life for different asset categories; predicted outcomes were re-circulated among for example structures are expected to last 30 to the experts for comment to achieve a consensus 100 years, while concrete stormwater drainage of opinion and ensuring that no one person had has a life of 80-100 years. The diagrammatic undue influence on the outcome representation of the assets also shows that in the case of assets like ITS with a short life, there zz Interviews with key technical experts is plenty of time to implement modification to zz Interviews with key external stakeholders asset specifications to cope with climate change including Wyndham City Council; Victorian impacts and as such, based on current climate Centre for Climate Change Adaptation and change projections adaptation for ITS assets does Research; Association of Bayside Municipalities; not need to be considered until around the year Westernport Local Coastal Hazard Assessment 2050. By comparison, for longer lived asset types Group; Western Alliance for Greenhouse like drainage, adaptation actions will need to Adaptation; and Climate Resilient Communities commence within the next fifteen years to ensure of the Barwon South West. these actions are effective in managing risk. zz Root cause analysis – for identifying a problem
and discovering the causes that led to it The initial identification of susceptible assets and activities found a significant number of risks existed across a wide range of assets types. The distribution of risk level by asset type is summarised in Table 5.2. The detailed risk assessments are contained in Sections 6.1 to 6.5.
Table 5.2 Distribution of Risk Level by Asset Type
Significant Important Insignificant Positive Asset Type Risks (#) Risks (#) Risks (#) Benefits (#) Road Pavements 1 1 3 1 Road Surfacing Layers 2 2 1 - Drainage 1 2 2 - Roadsides - 3 2 - Structures 1 1 3 - ITS/Electrical Assets 1 3 1 - VicRoads Activities 1 3 1 4 Total 7 15 13 5
18 Legend ITS The number of years before adaptation would need to start or occur Road surfacing The expected or design life of an asset class Roadsides - landscaping
Road Structural Component
Drainage
Roadsides - remnant/vegetation
Structures
20 40 60 80 100 120 Years
Figure 5.3 Design Life of Different VicRoads Asset Categories.(Adapted from (UK Highways Agency, 2011))
CLIMATE CHANGE RISK ASSESSMENT 19 6. Detailed Risk Assessment 6.1 Sea Level Risk Of all the climate change parameters, sea level More detailed information on projected changes rise is likely to have the greatest impact on the to climate parameters was used to assist in the performance of the road network. A summary detailed assessment of risks, with this being used to of the risks posed to infrastructure types by sea inform the prioritisation of a number of these risks. level rise is summarised in Table 6.1. Even though these impacts are limited to road assets in lower- lying coastal regions in the majority of cases, the All descriptions are described in terms of consequences are significant because many of the how they affect road infrastructure, relative affected roads in these regions form vital transport to the period 1980-1999 (referred to as the and accessibility links on the main road network. 1990 baseline for convenience). The Victorian Planning Provisions Section 10 requires an allowance for possible sea level rise. The 50th percentile (the mid-point of This is 0.2 m by 2040 for urban infill projects the spread of model results) provides a and 0.8m by 2100 for coastal projects (Victorian best estimate result. The 10th and 90th Planning Provisions Section 10 Clause 13, 2014). percentiles (lowest 10% and highest 10% of Figure 6.1 shows a timeline of sea level rise impacts the spread of model results) provide a range for the IPCC AR4 and IPCC AR5 projections as well of uncertainty. as the likely timeframe required to adequately adapt All CSIRO sourced data is produced with to sea level rise. For example, if the predicted level permission from CSIRO Australia. of impact associated with a 0.2m sea level rise was to occur at the earliest predicted timeframe i.e. 2034, then investigation of adaptation measures should commence for this by 2024 to ensure adequate time for project planning, funding and implementation. It is also worth noting that if sea level rise continues at its current rate, then 0.2 m or sea level rise will occur by 2060.
Background planning and Background planning and detailed modelling (2 years) detailed modelling (2 years)
Business cases (4 years) Business cases (4 years)
Detailed design (2 years) Detailed design (2 years)
Construction (2 years) Construction (2 years)
2014 2020 2030 2040 2050 2060 2070 2080 2090 2100
Range for 0.2m SLR Range for 0.47m SLR
(2013 data) IPCC ARS RCP 8.5 scenario
Sea Level Rise 0.2m 0.47m 0.82m (2007 data) IPCC AR4 A1FI scenario
Figure 6.1: Comparison of IPCC AR4 and AR5 Sea Level Rise Projections and Time Implications for Adaptation
20 Table 6.1: Summary of Sea Level Rise Related Risks to Infrastructure Types
Consequences Actions Risk Road Surfacing Sea Level Rise may result in mechanical damage to Investigate need to Significant road surfaces through wave action or storm surge. construct protective This potential will be limited to locations where sea measures. Consult level rises sufficiently to inundate the road pavement. with state and local The ingress of salt into road pavement material government over below the road surface due to higher sea levels has options to rebuild or the potential to cause de-lamination of the road realign affected routes surfacing. However, this is a very rare occurrence. clear of tide and storm surge levels. Pavement Structure Sea Level Rise may result in mechanical damage such as scour or erosion to road pavements as a result of wave action or storm surge. This potential will be limited to locations where sea level rises sufficiently to reach the road pavement Drainage One of the early impacts of sea level rise may be the reduced capacity of coastal or low lying drainage networks with submerged outfalls. This will increase the likelihood of flooding during rain events, especially at high tide times. This risk is likely to become apparent well before the risks associated with the overtopping of road pavements Structures Overtopping by sea water, especially of embankments and approaches may pose a problem in some areas. - Scour due to storm surge could cause instability and failure for structures like bridges, culverts and retaining walls - Changes in salinity of groundwater, and the height of the tidal zone may increase the risk of corrosion in some coastal areas. Operations Planning of new infrastructure and approval of local government development proposals will need to take account of changes to the road network associated with sea level rise. Many of these decisions may involve multiple agencies, or may be dependent on strategies to be developed by or in conjunction with third parties. Experience has shown that these issues may take many years to resolve. ITS/Electrical Assets Some cables and signal and lighting hardware may be affected, particularly in urban areas. There are no significant risks to ITS assets from No action required Insignificant sea level rise as no ITS assets are located close to at this stage the coast. Roadsides Sea Level Rise may result in mechanical damage to No action required Important roadside assets including signs and safety barriers. at this stage Vegetation management may also be impacted by rising water table, increasing salt levels, and inundation. Roadsides will be managed by VicRoads as part of Figure 6.1: Comparison of IPCC AR4 and AR5 Sea Level Rise Projections and Time Implications for Adaptation the overall sea level rise risk, as it is required within the road network.
CLIMATE CHANGE RISK ASSESSMENT 21 The expected sea level rise and storm surge Urban areas likely to be impacted include impacts expected in Victoria are described in Table Williamstown, St Kilda, Elwood and Edithvale. 4.1. Table 6.2 and Table 6.3 show VicRoads analysis There is also projected impact to locations such of the estimated impact of storm surge and sea as Queenscliff and the Great Ocean Road. level rise on the Victorian main road network. Based on the projections of 0.82m of sea level They are based on analysis by VicRoads using the rise, it is estimated that inundation would impact Victorian Coastal Inundation Dataset (DEPI b, 2013) 26 roads, directly affecting around 14 kilometres in and as such are a conservative estimate. carriageway length. An additional ten kilometres of The impacts are likely to be the highest in the roads are likely to have impact to subgrades and Eastern Region, accounting for approximately half batters at this time, as well as damage to other of all projected impacts. This includes a number assets in the vicinity. of Gippsland regional locations such as Lakes Entrance, Tooradin and near Tarwin Lower.
Table 6.2: Estimated Sea Level Rise Impacts on Main Roads by Region
VicRoads 0.2m Sea level rise 0.47m Sea level rise 0.82m Sea level rise Eastern Region 0.0 2.5 6.8 Metro South East 0.2 0.5 1.2 Metro North West 0.0 0 2.1 South Western Region 1.0 1.8 3.7 TOTAL km 1.2 (5 roads) 4.8 (12 roads) 13.8 (26 roads)
Although the impacts of inundation due to Storm surge is also likely to increase from the rising sea levels may not become obvious for current 1.0 to 2.1 m to 1.6 to 2.7 m by 2070, with many decades, other adverse impacts may be the highest surges predicted between Lorne and experienced much earlier, in fact a number of Loch Sport (Department of Sustainability and locations already experience storm surges impacts, Environment, 2012). The impact of storm surges is resulting in periodic road closures or traffic hazard also predicted to increase, with sea level rise. Based speed reductions. There are also locations along on the projections of 0.8 m of sea level rise it is the Great Ocean Road, such as Port Campbell estimated that 62 roads, with 89.6 kilometre length where the road has been realigned to address would be impacted by 1 in 100 year storm events. existing coastal erosion risks. The impacts of sea level rise and storm surge are not uniform across the Victorian Coast.
Table 6.3: Estimated Storm Surge Impacts on Main Roads by Region
VicRoads 0.2m Sea level rise 0.47m Sea level rise 0.82m Sea level rise Eastern Region 17.3 31.2 44.9 Metro South East 1.3 4.4 11.2 Metro North West 0.5 3.2 19.8 South Western Region 3.9 6.7 13.6 TOTAL km 23.0 (30 roads) 45.6 (42 roads) 89.6 (62 roads)
22 It is also predicted that sea level rise will lead to Westernport Bay being muddy, and becoming erosion of new sections of coastline and this will lead sandier towards the east of the state. Some of the over time to collapse of infrastructure in susceptible specific coastal areas predicted to be impacted locations. Erosion is also predicted to undermine over are also listed in Table 6.5 and underline the need two kilometres of the Great Ocean Road by 2040 and to consider the particular nature of the coastal 13 kilometres by 2100 (SKM, 2012). Table 6.4 shows geology when determining adaptation response. the composition of the Victorian coastline, which is heterogeneous, with the western part of the state having more rocky coastlines,
Table 6.4: Victorian Coastline Type by Regional Area
# Victorian Coastline of CapeWest Otway Cape Otway to Torquay to Torquay Westernport toWesternport Entrance Lakes East of Lakes Entrance Rocky Hard rock cliffs 22% 39% 17% 6% 15% 16% Coasts Soft rock cliffs 6% 26% 18% 8% 0% 4% Sandy shores backed 30% 1% 10% 46% 18% 59% by soft sediment Sandy Sandy coast/ shores 21% 34% 55% 30% 10% 21% and backed by rock Muddy Muddy Sedimentary 22% 0% 0% 10% 57% 0% Coasts shores (e.g. tidal flats)
Based on OzCoasts Data (OzCoasts, 2013) # Sourced from (Department of Sustainability and Environment, 2012)
Table 6.5: Coastline Compositions at Locations Projected to be Impacted by Sea Level Rise Peterborough Apollo Bay Creek Skenes River Kennett Wye River Angelsea Barwon Heads Queenscliff Inverloch – Bay Road Venus Rocky Hard rock cliffs 0% 0% 0% 36% 8% 0% 0% 0% 0% Coasts Soft rock cliffs 33% 8% 5% 0% 0% 0% 0% 0% 0%
Sandy shores backed 53% 48% 71% 2% 4% 21% 100% 94% 86% by soft sediment Sandy Sandy coast/ shores 14% 44% 24% 62% 88% 79% 0% 6% 13% and backed by rock Muddy Muddy Sedimentary Coasts 0% 0% 0% 0% 0% 0% 0% 0% 1% shores (e.g. tidal flats)
Based on OzCoasts data (OzCoasts, 2013)
CLIMATE CHANGE RISK ASSESSMENT 23 The cost impact of storm surge events would be 6.2 Temperature expected to rise as greater lengths of road are A summary of the risks posed to Infrastructure impacted by storm surge events. Within the Great types from rainfall is shown in Table 6.6. This is Ocean Road an additional 13.8km of road length based on an assessment of information on rainfall would be susceptible to 1 in 100 year storm surge volumes, intensity, humidity and evapotranspiration events (SKM, 2012). These events would also affect shown in Table 4.1, and supported by the additional other co-located roadside assets such as batters with analysis below. geotechnical risk, structures, vegetation and fencing. Average temperatures in Victoria are predicted to Many VicRoads drainage networks discharge into rise by between 1.5 and 2 °C on average across the drainage systems managed by local government state by 2030 and by 3 and 5 °C on average across or other government agencies. As such, the the state by 2070 at the 90th percentile. There will infrastructure likely to be damaged by flooding of also be a corresponding increase in warm days. the road drainage system includes infrastructure These are based on CSIRO modelling, shown in other than roads with buildings, agricultural land and Table 4.1, and represent the worst case scenario. commercial and industrial developments close to coastal areas also under threat. At many locations, It is also expected that hot spells (a period a 3 to 5 VicRoads will not be able to take independent action consecutive days where the temperature exceeds to address this issue and it will require a coordinated 35 oC) will double from 1 to 2 by 2070. Night approach to determine the most efficient solutions time temperatures in Australia are expected to rise involving all interested parties. with warm nights (>21 °C) projected to increase between 15-50 per cent at the end of the 21st Century (Maunsell, 2008), as shown in Table 4.1.
Table 6.6 : Summary of Temperature Related Risks to Infrastructure Types
Consequences Actions Risk Road Surfacing Greater potential for damage under heavy wheel loads. No action required at Important this stage Pavement Structure No significant consequences No action required Insignificant Drainage No significant consequences No action required Insignificant Roadsides Combined with lower rainfall will result in the loss of many Investigate Significant plant species and less vigorous growth of many of the vulnerable species, survivors. This could result in greater erosion, landslips, locations. Possible increased fire risk, issues with management of pest plants alternative plantings and animals, loss of landscape amenity. at key locations. Structures No significant consequences No action required Insignificant ITS/Electrical Assets Extended high temperatures may have an adverse impact No action required at Important on the operation of some electrical equipment, such as this stage. components in traffic control cabinets or LED’s used in traffic and street lighting. Operations Heat Stress may become a major health issue especially in Investigate possible Important inner urban areas with the urban heat island effect playing actions to ameliorate a major role. urban heat island OH&S provision for Field workers may require change. effect and the Maintenance timeframes may decrease due to the impact contribution of roads on assets such as LED’s in street and traffic lighting. to this. Extended season for temperature sensitive works such as No action required at Positive laying bitumen/asphalt this stage. Decreased risk of black ice on roads No action required Positive
24 6.3 Rainfall However, for the worst case scenario is represented A summary of the risks posed to Infrastructure by the based 10th and 90th percentile of data the types from rainfall is shown in Table 6.7. This is rainfall volume will be somewhere between a 20% based on an assessment of information on rainfall increase and a 40% decrease, with the forecast volumes, intensity, humidity and evapotranspiration increases in the 90th percentile largely falling within shown in Table 4.1, and supported by the additional existing design parameters.. analysis below. Overall rainfall intensity will increase by about 1% in Table 4.1 shows there may be less annual rainfall Victoria by 2030 and about 6.5% by 2070 relative to volume, but rainfall events are likely to be become a 1990 baseline as shown in Table 6.8. The number more intense with a higher risk of localised and of rainy days will decrease by about 5% by 2030 widespread flooding. Extreme rainfall events and about 17% by 2070 relative to a 1990 baseline will also become 30% more intense by 2030. In as shown in Table 6.9. this timeframe it is anticipated that the extent of Humidity levels are forecast to reduce slightly, with a flooding will be 25% larger for 1 in 5 year events and less than a five percent decrease by 2070 at the 10th 15% larger for 1 in 100 year events in Melbourne percentile, based on CSIRO modelling and shown in urban catchments. It is also suggested that the Table 4.1. This represents the worst case scenario. frequency of a current 1 in 100 year rainfall event will double (Pedruco & Watkinson, 2010). Evapotranspiration levels are predicted to increase with a greater than 16% change by 2070 at the Annual rainfall volume is likely to decrease in 90th percentile, based on CSIRO modelling and Victoria. It is predicted to decrease by 0.2 to 0.5% shown in Table 4.1. This is projected to result in an by 2030 and by 10 to 20% by 2070 for the 50th increased movement of water to the atmosphere percentile based on CSIRO modelling, as shown from both water bodies and from vegetation, and in Table 4.1. represents the worst case scenario.
Table 6.7: Summary of Rainfall Related Risks to Infrastructure Types
Consequences Actions Risk Road Surfacing No significant consequences No action required Insignificant Pavement Structure More intense rainfall patterns could result in ponding of water at some Attention to maintenance Insignificant locations, with the possibility of pavements being weakened in local of drainage systems in areas. vulnerable areas. If the increased intensity of rainfall events result in ponding of surface water adjacent to pavements, this could result in increased rates of pavement deterioration at the locations where the ponding occurs. In most instances, good drainage maintenance practice would reduce this issue from occurring. Overall drier conditions will result in longer pavement life. No action required Positive Drainage More intense rainfall could result in localised flooding, damage due to Investigate locations of Important scour, less safe running conditions for traffic during rainstorms on wide vulnerability, possible flat pavements. protective measures, traffic management measures Roadsides Combined with higher temperature will result in the loss of many Investigate vulnerable Important plant species and less vigorous growth of many of the survivors. This species, locations. Possible could result in greater erosion, landslips, increased fire risk, issues with alternative plantings at key management of pest plants and animals, loss of landscape amenity. locations. Structures More intense rainfall could result in localised flooding, damage due to Investigate locations of Insignificant scour, less safe running conditions for traffic during rainstorms on wide vulnerability, possible flat pavements. protective measures, traffic management measures ITS/Electrical Assets No significant consequences No action required Insignificant Operations Less natural water available for maintenance and construction No action required at this Important Possible need to harvest rainfall runoff from road. stage. Fewer rain related delays to construction and maintenance works. No action required Positive
CLIMATE CHANGE RISK ASSESSMENT 25 Table 6.8: Summary of Projected Rainfall Intensity Changes
Rainfall Intensity (%) [10th to 90th percentile] Region Location 2030 Medium 2070 low 2070 high Port Phillip and Westernport Melbourne 0.9 [-7.7 to 15.2] 3 [-12.9 to 25.3] 5.9 [-24.9 to 48.9]
Scoresby 0.8 [-7.7 to 14.8] 2.6 [-12.8 to 24.7] 5 [-24.7 to 47.7]
Cape Schanck 0.7 [-9.7 to 14.9] 2.3 [-16.2 to 24.8] 4.5 [-31.4 to 47.9]
Corangamite Ballarat 1.5 [-10.5 to 15.8] 5 [-17.4 to 26.4] 9.6 [-33.7 to 51]
Lismore 1.3 [-10.3 to 15.6] 4.5 [-17.1 to 26.1] 8.6 [-33.1 to 50.4]
Glenelg Hopkins Ararat 1.1 [-6.8 to 15.8] 3.6 [-11.3 to 26.4] 6.9 [-21.8 to 51]
Hamilton 1.5 [-7.3 to 15.5] 5 [-12.1 to 25.9] 9.7 [-23.4 to 50]
Warrnambool 3.1 [-10.2 to 16] 5.2 [-17 to 26.7] 10.2 [-32.8 to 51.5]
Wimmera Horsham 0.6 [-8.8 to 14.8] 2.1 [-14.7 to 24.7] 4 [-28.4 to 47.7]
Mallee Mildura -0.3 [-11.1 to 16.1] -1.1 [-18.5 to 26.8] -2 [-35.7 to 51.8]
Ouyen -0.3 [-9.6 to 15.6] -1.1 [-16 to 25.9] -2.1 [-31 to 50.2]
North Central Donald 0.6 [-11.2 to 15.2] 2 [-18.7 to 25.4] 3.9 [-36.2 to 49.1]
Bendigo 1.1 [-7.2 to 15.9] 3.6 [-12.0 to 26.6] 6.9 [-23.3 to 51.4]
Swan Hill 0.6 [-8.5 to 15.3] 1.9 [-14.2 to 25.5] 3.6 [-27.4 to 49.3]
Goulburn Broken Tatura 0.8 [-7.1 to 14.6] 2.8 [-11.9 to 24.4] 5.3 [-23 to 47.1]
Benalla 0.9 [-9.0 to 13.5] 3.2 [-15.0 to 22.4] 6.1 [-29 to 43.4]
Mangalore 1.2 [-7.1 to 15.1] 3.8 [-11.9 to 25.2] 7.4 [-22.9 to 48.7]
North East Beechworth 1.4 [-10.1 to 14.4] 4.8 [-16.8 to +24.0] 9.2 [-32.4 to +46.3]
Rutherglen 1.5 [-9.8 to 14.4] 5.1 [-16.4 to +24.0] 9.9 [-31.7 to 46.4]
Omeo 2.1 [-8.6 to 17.5] 7 [-14.3 to 29.2] 13.6 [-27.7 to 56.4]
East Gippsland Orbost 1.0 [-7.4 to +19.2] 3.2 [-12.3 to 32.0] 6.2 [-23.8 to 61.8]
Lakes Entrance 1.5 [-7.7 to +18.4] 4.9 [-12.8 to 30.7] 9.5 [-24.7 to 59.4]
West Gippsland Wonthaggi 0.4 [-7.7 to 14.3] 1.4 [-12.8 to 23.8] 2.7 [-24.8 to 46.0]
Sale 1.5 [-5.3 to 16.6] 4.9 [-8.8 to 27.7] 9.4 [-17.0 to 53.5]
Source Regional Climate Change Projection Publications by Region (DSE a,b,c,d,e,f,g,h,I,j, 2008)
26 Table 6.9: Summary of Projected Changes to the Number of Rainy Days
Rainfall Intensity (%) [10th to 90th percentile] Region Location 2030 Medium 2070 low 2070 high Port Phillip and Westernport Melbourne -6 [-17 to -1] -10 [-28 to -2] -19 [-54 to -4]
Scoresby -6 [-16 to -1] -10 [-26 to -2] -19 [-51 to -4]
Cape Schanck -6 [-13 to -1] -10 [-22 to -2] -19 [-43 to 5]
Corangamite Ballarat -5 [-17 to -1] -9 [-28 to -2] -18 [-54 to -5]
Lismore -5 -[15 to -2] ‘-9 [-25 to -3] -17 -[48 to -5]
Glenelg Hopkins Ararat -6 [-13 to -1] -10 [-22 to -2] -18 [-43 to -5]
Hamilton -5 [-17 to -2] -8 [-28 to -3] -16 [-54 to -5]
Warrnambool -5 [-17 to -1] -9 [-29 to -2] -18 [-56 to -4]
Wimmera Horsham -6 [-19 to -1] -10 [-31 to -2] -19 [-61 to -4]
Mallee Mildura -6 [-21 to 0] -10 [-35 to 1] -19 [-68 to 2]
Ouyen -7 [-20 to -1] -11 [-33 to -1] -21 [-64 to -2]
North Central Swan Hill -6 [-20 to -1] -10 [-34 to -1] -18 [-66 to -2]
Donald -6 [-18 to -1] -9 [-31 to -2] -18 [-83 to -6]
Bendigo -5 [-17 to -1] -8 [-29 to -2] -16 [-56 to -4]
Goulburn Broken Tatura -5 [-17 to -1] -9 [-29 to -2] -17 [-56 to -3]
Benalla -5 [-18 to -1] -8 [-30 to -2] -16 [-57 to -3]
Mangalore -5 [-17 to -1] -8 [-29 to -2] -16 [-56 to -4]
North East Rutherglen -5 [-18 to -1] -8 [-30 to -2] -16 [-57 to -3]
Beechworth -5 [-18 to -1] -8 [-28 to -2] -16 [-57 to -3]
Omeo -5 [-17 to -1] -8 [-28 to -2] -15 [-54 to -3]
East Gippsland Orbost -5 [-16 to -1] -8 [-26 to -1] -15 [-51 to -2]
Lakes Entrance -5 [-16 to -1] -8 [-26 to -1] -15 [-51 to -3]
West Gippsland Wonthaggi -5 [-14 to -1] -9 [-23 to -2] -18 [-44 to -5]
Sale -5 [-13 to -1] -8 [-21 to -2] -16 [-41 to -2]
Source Regional Climate Change Projection Publications by Region (DSE, a,b,c,d,e,f,g,h,I,j, 2008)
CLIMATE CHANGE RISK ASSESSMENT 27 6.4 Extreme Weather Events The Forest Fire Danger Index (FFDI) is predicted to A summary of the risks to VicRoads infrastructure increase, and this will result in a likelihood of more from extreme weather is shown in Table 6.10, based fire events across Victoria. Table 6.11 shows high on wind speed, fire risk and changes to rainfall and extreme fire risk days and Table 6.12 shows intensity. This section considers rainfall relating to only extreme fire risk days, and both predict an extreme events as discussed in section 6.3. increase in risks through to 2070. For example, in Bendigo the number of days experiencing high Wind speed analysis is based on CSIRO modelling or extreme fire weather is predicted to increase (CSIRO, 2007 a), in Table 4.1. This shows an from 14 days to 19 days annually by 2020 and 29 increase in wind speeds measured 10 metres above by 2050 in a worst case scenario, and the number the ground of up to five percent by 2030 and ten of extreme fire risk days is predicted to increase to to 15 percent by 2070 at the 90th percentile, and between 1.5 and 2 by 2020 and 1.6 and 4 by 2050. represents the worst case scenario.
Table 6.10: Summary of Extreme Weather Related Risks to Infrastructure Types
Consequences Actions Risk Road Surfacing Increased bushfires and flood may cause more Investigate locations of Important frequent and more extensive damage to road surfaces vulnerability, possible protective measures, and Pavement Structure Greater likelihood of widespread flooding could result in pavement damage and long term reduction of life flood flow management for affected pavements. measures. Drainage Greater likelihood of widespread flooding could result in damage to drainage systems. Roadsides Greater likelihood of bushfires, floods and storms will cause difficult conditions for many plants and animals. Structures Greater likelihood of widespread flooding and storms could result in damage to structures and their footings. ITS/Electrical Assets Greater reliance on traffic management systems Investigate potential Important to reduce congestion, ensure smooth traffic flow locations for installation especially during extreme weather and emergency of uninterrupted power management events supply Operations Greater pressure on emergency response resources. No action required Important at this stage. Decreased operational impacts of black ice and snow No action required Positive on roads
Table 6.11: Summary of Projected High and Extreme Fire Days (CSIRO, 2007 b)
Location Present (1973 – 2007) 2020 2050 Melbourne Airport 14.8 15.7 to 18.6 16.2 to 23.6 Mildura 56.6 59.5 to 66.9 62.3 to 90.5 Laverton 11.8 12 to 13.6 12.4 to 19.2 Bendigo 13.9 15.6 to 18.4 16.6 to 28.6 Sale 5.4 5.4 to 7.1 5.7 to 11.1
28 Table 6.12: Summary of Projected Extreme Fire Days (CSIRO, 2007 b)
Location Present (1973 – 2007) 2020 2050 Melbourne Airport 2.5 2.8-3.4 3 to 5.8 Mildura 7.3 8.0 to 10.0 8.6 to 15.9 Laverton 1.9 1.9 to 2.6 2.2 to 4.6 Bendigo 1.2 1.5 to 2.0 1.6 to 4.0 Sale 0.6 0.6 to 0.9 0.6 to 1.9
6.5 UV Level This represents the worst case scenario. By 2070 A summary of the Risks by Asset types is shown UV is predicted to be more like that currently in Table 6.13. This is supported by the prediction experienced by Sydney based on data from BOM that downward solar radiation will increase by two (BOM) and CSIRO (CSIRO, 2007 a) with an increase percent by 2030 and by ten percent by 2070 at the from 6 to 6.3. 90th percentile, based on CSIRO modelling, shown in Table 4.1.
Table 6.13: Summary of Radiation Risks by Asset Type
Consequences Actions Risk Road Surfacing Increased radiation will accelerate Investigate most efficient way Significant the rate at which bituminous surfaces to manage surface materials to became brittle due to oxidation, thus adapt to future UV levels. requiring more frequent resurfacing. Pavement Structure No significant consequences No action required. Insignificant
Drainage More intense rainfall could result in No action required. Insignificant localised flooding, damage due to scour, less safe running conditions for traffic during rainstorms on wide flat pavements. Roadsides Higher levels of UV radiation may cause No action required at this Important more rapid deterioration of items such as stage. plastics materials used in road furniture, and the reflective faces of signs Structures No significant consequences No action required. Insignificant
ITS/Electrical Assets Some plastic or perspex housings or No action required at this Important casing may require replacement or stage. redesign. Operations No significant consequences No action required. Insignificant
CLIMATE CHANGE RISK ASSESSMENT 29 6.6 Prioritising Risks Of all the risks assessed only sea level rise and In order to better focus VicRoads actions these elements of rainfall, radiation and temperature identified risks have been prioritised, on the were considered to be significant risks to the road basis of the assessed level of risk, the design life network. Changes in projected climatic parameters of the assets and also the estimated time until will, however, also have benefits for the road changes in climate would impact on the assets network, such as: performance in the road network (refer Table 6.14). zz a decreased likelihood of black ice on Victorian All significant risks have been identified as priorities. roads through increased average overnight In addition, whilst the impact on drainage was temperatures assessed as “important”, it has also been classified as a prioritised risk because the stormwater zz less operational impacts to the road network drainage is an asset with a long design life and the from snow, which will also result in less salt impacts are likely to be experienced in the short impact to the local environment to medium term. Another example is the impact zz a likely increase in the life of the structural on roadsides impacted by storm surge and sea pavement component of the road due to level rise. This was assessed as “important”, but has higher temperatures and decreased humidity been prioritised as it is an integral part of the road levels leading to drier subgrades and pavement network in areas caused by sea level rise. structural layers
zz a decrease in the annual rainfall (particularly in Spring) will lengthen the available road sealing season, as well as the annual road construction window. However, this is likely to be offset by construction disruption from increased summer temperatures and heatwaves
zz a possible decrease in the amount of contingency in contracts for inclement weather. Nonetheless, all risks will continue to be monitored and assessed as new information and asset monitoring data becomes available.
30 Table 6.14 Summary of Prioritised Risks and the Impacts of Climate Change on Assets and Customers
Climate Parameter Asset Type Impact on Asset Impact on Road User Sea Level Rise Road Pavement Higher impact from storm surges and Reduced availability due Road Surfacing Layers permanent inundation of coastal road to road closures from assets including pavements. storm surge events and Drainage Potential for widespread damage to all road sea level rise. Roadside infrastructure including pavements and Structures structures, due to rising sea levels, resulting ITS/Electrical Assets in flooding and road closures. Flooding may also occur during rain storms in areas VicRoads Activities where drainage efficiency is affected by reduced fall to outlet. Rainfall Drainage Increased incidence of intense rainfall Increased risk of could result in localised flooding, increased aquaplaning especially stress on drainage systems, damage due on wide flat surfaces to scour, less safe running conditions and localised network for traffic during rainstorms on wide operational issues due to flat pavements. In addition to localised flooding. scouring of roadsides and bridge structures this would increase the risk of landslides. The decrease in annual rainfall and Decreased amenity of the rainy days combined with increased journey whilst improving temperatures and increased driving conditions. evapotranspiration will lead to degraded roadsides especially remnant and landscaped roadsides. This is turn will lead to increased incidence of weeds and other invasion species. Radiation Road Surfacing Layers The increased level of UV could contribute Reduced availability due to the increased rate of pavement oxidation to increased road closure and result in a shorter expected life of for maintenance. the pavement surface, especially for a spray seal surface. Potential for increased maintenance costs Temperature Roadsides Increased in average temperature will Decreased accidents from lead to reduction in black ice incident and poor driving conditions. snowfall but would lead to a decrease Improved travel times. in the life of some electrical assets, particularly LED lights. Increase in frequency of warm nights will increase heat retention further exacerbating the heat island effect. Increase in frequency of very hot days and lower rainfall will result in the loss Reduced availability of many plant species and less vigorous due to road closures for growth of many of the plant survivors. This maintenance. could result in greater erosion, landslips, increased fire risk, issues with management of pest plants and animals and loss of landscape amenity. It will also increase the stress on expansion joints on bridges and lead to softening and Decreased amenity of the deformation of spray seal roads journey.
Derived from (UK Highways Agency, 2011)
CLIMATE CHANGE RISK ASSESSMENT 31 7. Developing Adaptation Sections of the South Gippsland Highway along the north end of Westernport Bay between Tooradin Responses and Koo Wee Rup have been identified as being Whilst specific adaptation responses will be at risk of inundation and sea level rise within 50 progressively developed, an amount of research years. This road is a major tourist route, important and discussion has already occurred regarding regional access arterial and major transport route. possible approaches to adaptation and these are Some of the properties and local agriculture served discussed in more detail below. In addition, it is by this road may need to be relocated to higher recognised that a key component of adaptation ground. The highway itself could be raised in situ, includes the “soft systems” such as the ability to but the most appropriate route for a flood proof generate, access and interpret information about facility may involve the development of a new climate change and its likely impacts; suitable road on a new alignment, in coordination with the methods for identifying and assessing potential relocation of other community infrastructure and adaptation strategies; appropriately skilled people; industrial/commercial/agricultural activity. adequate financial resources; strategic planning and Sea level rise will also need to be taken into account governance systems that will embrace adaptation in the planning of new residential and infrastructure planning; and above all, a willingness to adapt. developments in coastal areas. Consideration of sea As such, inter-disciplinary and inter-agency studies level rise is already affecting the conditions imposed will be important requiring engagement with all on approved development proposals for both new stakeholders in order to build resilience and reduce and existing coastal properties. As a potential referral vulnerability to climate change. authority as well as a proponent, a documented rational approach showing how climate change 7.1 Sea Level Rise risk such as sea level rise is being considered and Given the discussion in section 6.1, it is clear sea managed on the main road network will aid decision level rise will affect all asset types in those locations making across Government. impacted. In some instances, it may be possible to Early estimates of the costs of responding to sea rebuild affected roads, within the current reserve, at level rise through relocation of road assets indicate a higher level, and where this is not possible, other significant expenditure over multiple years will be adaptation responses will be necessary. An example required based on a 0.8 m sea level rise. This is of this would be realigning the road further from based on currently available data sources and needs the coast. However, this would be a significant refining at an early stage to be able to provide advice undertaking with potential for significant impacts on to government of the risks of sea level rise. local communities, other infrastructure and cultural and biodiversity values as a minimum, with significant Consultative links need to be developed implications for some land owners and developers. with relevant government departments, local government and agencies to ensure the response Infrastructure associated with housing, industry and to sea level rise is rational and consistent and able agriculture is also likely to be affected by sea level to be managed appropriately, including information rise and therefore any change to road infrastructure to affected sections of the community. will need to be considered in association with other related industries and activities. The effects of sea level rise will initially be exhibited through local drainage issues and coastal erosion. Accordingly, investigation of sites vulnerable to these issues should have a high priority for investigation. However, investigation of long term effects will also need to be completed before an appropriate assessment can be made of the most cost-effective economic solution.
32 Summary of Sea Level Rise Actions A number of actions will need further investigation including; §§ confirming the projected sea level rise and storm surge impacts through ongoing review and consultation §§ confirming cost estimates for predicted impacts §§ developing special bridge standards for flood prone areas §§ identifying appropriate protective measures and situations where they should be considered §§ consulting with State government departments, catchment authorities and local government regarding the options for rebuilding or realigning affected routes to protect for sea level rise and projected storm surge §§ undertaking a case study to gain further insights into climate adaptation.
Edithvale Road has been identified as a location at risk of sea level rise and storm surge. Given it is a well established location with assets belonging to Melbourne Water, Kingston Council and VicRoads, it is being developed as a case study of how adaptation can work with multiple stakeholders. The case study will identify what adaptation would best suit the locations and stakeholder needs. It will also aim to examine the likely timeframes for adaptation in this location. The figure below shows the projected extent of sea level rise based on DEPI Future Coasts projections to 2100, with storm surge impacting the area more widely.
CLIMATE CHANGE RISK ASSESSMENT 33 7.2 Temperature Summary of Temperature Responses Vegetation has been shown to have strong links A number of actions will need further to the community’s sense of place (Kendall, 2011). investigation including; Plane trees are an example of this in the City of Melbourne and are currently one of the most § determining ‘at risk’ species through prominent tree types (City of Melbourne, 2015). literature, monitoring and anecdotal sources They are also susceptible to leaf burn on hot days § determining options for replacement of (Nicholson, 2014), which can lead to distress and in vegetation species on roadsides, which are some cases tree death. A number of roadsides and better suited to the expected climate established urban tree species across Victoria were § adversely impacted by the Millennium drought, investigating opportunities for increasing however, it is understood that soil, water availability, soil water availability including the use of microclimate and topography will also influence stormwater in watering roadside vegetation vegetation health. Broadleaf deciduous trees may § ensuring data relating to the location be less successful in future climates than narrow and frequency of road closures due to leaved, evergreen trees which may be at less risk temperature softening of pavements is (Kendal & McDonnell, 2014). Other species, such captured as golden wattle, are less susceptible as they have § investigating the relationships between vertically oriented phyllodes, which minimise the landslips and the vegetation condition of amount of direct sun exposure (Australian Plants roadsides Society, 2011). § investigating the contribution of the main To assist in better identifying and quantifying areas road network and urban vegetation to the of risk, VicRoads will investigate species likely urban heat island effect and options for to be at risk, as well as identifying replacement mitigation species that are better suited to expected future climate characteristics in roadsides. This will include locations with existing geotechnical risks, particularly if the existing vegetation is susceptible to climatic changes, where a lack of action may cause an increase in the risks of landslip. The urban heat island effect is a temperature related impact on the public in areas with significant amounts of built infrastructure. Asphalt roads contribute to the effect through both their dark colour and the tonnages of materials within the constructed roads and this is expected to be exacerbated by increases in night time temperatures. Further work will be undertaken to understand the specific contribution of the main road network to the urban heat island effect and develop responses as appropriate.
34 7.3 Rainfall Summary of Rainfall Responses Updated rainfall intensity, frequency, duration (IFD) A number of actions will need further projection data has now been released as part of a investigation including; larger rainfall and intensity project undertaken by the Bureau of Meteorology. The updated IFD data now §§ reviewing the updated IFD information includes information from 1983 to 2012 in its dataset, once released and determine implications as well as addition stations measuring rainfall. for road design and site management during construction Figure 7.1 displays an estimation of the percentage §§ change when comparing this revised data to the developing technologies which allow existing IFD data for the typical road drainage automatic detection and communication of flooding on managed motorways design event (10% AEP of 10 minute duration). The main observation is a 10-20% increase in the §§ investigating options to decrease the intensity across the south eastern suburbs for this potential for aquaplaning at locations type of event. identified as being at risk One of the asset types likely to be impacted §§ ensuring operational personnel are aware by more intense rainfall events is pavements, of the likely changes in rainfall intensity particularly wide flat pavements and roads and the importance of ensuring drain with narrow shoulders. In most cases, it is not cleaning is consistently undertaken practicable to alter existing pavements (such as increasing crossfall) to reduce the likelihood Percent Change: 10min, 10% AEP (estimated) of a flow depth that could lead to aquaplaning conditions; nor is it generally practicable to alter the flow capacity of shoulders and kerbing. Consideration may instead be given to applying lower speed limits, temporarily closing lanes and/or warning signs during heavy rain conditions, with the aim of altering driver behaviour in the long term. The other asset types likely to be impacted by changes in rainfall intensity and volume are the underground drainage systems, and structures with pumped drainage. This means there will be an increased importance on the maintenance of existing assets to ensure the efficient operation of underground drainage systems.
Figure 7.1 Estimated Changes in Rainfall Intensity for Typical VicRoads Drainage Source from Bureau of Meteorology
CLIMATE CHANGE RISK ASSESSMENT 35 7.4 UV Level 7.5 Long Term Asset Responses Increased UV radiation will accelerate the rate at Whilst there are forecast impacts to different asset which bituminous surfaces became brittle due to classes through time, the appropriate approach is oxidation, thus requiring more frequent resurfacing. primarily guided by the likely lifespan of the assets. VicRoads will investigate whether or not the use For assets with short life spans (e.g. ITS), or periodic of alternative bitumen products such as polymer replacement requirements (e.g. pavement surfacing) modified binders will improve the whole of life adaptation measures will be implemented as a effectiveness. Increased UV levels will also have running change at an appropriate point in time. impacts on the design life of assets such as perspex However, a number of assets have significant lifetimes noise wall panels, roadside furniture and reflective as shown in Figure 5.1, particularly structural assets coatings on signage. such as bridges. In this case, adaptation measures will need to be built into the construction requirements of future assets. Summary of UV Responses Existing assets can be expensive to alter significantly A number of actions will need further during their lives. As such, a set of responses investigation including; will be needed to manage their lifecycle. This is § the use of polymer modified binders as a independent of one off events or trigger points cost effective treatment in road surfacing which can impact on roads (i.e. sea level rise or applications in specific locations flood), where a separate set of responses is required. Many existing assets have sufficient residual life such § establishing systems to collect performance that they will be impacted by climate change before data to assess any changes in condition of they reach the end of their operational lives. perspex noise panels or spray seals, which might indicate a shortening of their life Additionally there will need to be consideration as to how these assets are impacted by climate change; such as the resleeving and cathodic protection of bridge structures such as the Phillip Island Bridge. Sea level rise and increased heights of splash zone will need to be factored into an activity of this type. Accordingly, typical response options to mitigate or avoid climate change impacts on existing assets, in principle, include:
zz Undertake cost effective/appropriate/feasible alterations at some trigger point in the future (for example, undertake planned servicing/ rehabilitation with more resilient materials (at a higher cost);
zz Adopt a more intensive maintenance schedule (at a higher cost) to preserve level of service/ maintain serviceable lifespan; and
zz Accept lower level of service and/or shorter life to replacement/refurbishment.
Summary of Long Term Asset Responses A number of actions will need further investigation including; § developing appropriate adaptation measures to be built into the design of new assets § developing guidance or a decision making framework and criteria for the improvement, upgrade or replacement of assets § evaluating the whole of life costs of adaptation response options for existing assets such as bridges
36 7.6 Organisational Responses zz collaborating with the National Committee There are also a number of adaptation responses on Water Engineering of Engineers Australia around organisational and data collection in the ongoing review of the IFD to ensure opportunities which are not specific to any specific that the design of new works will be able to type of asset or climatic parameter but need to accommodate the changes in rainfall patterns associated with climate change. be investigated to provide baseline information from which VicRoads, in collaboration with key zz the development of information and guidance stakeholders, can make more informed decisions for identified knowledge gaps necessary to regarding climate change adaptation measures. more accurately understand climate change These include: risks and impacts. These areas include, but are not limited to: zz developing baseline information on network impacts from climatic parameters, to better §§ impact of fire on road pavements understand how any observed climate changes §§ contribution of VicRoads Assets to UHI effect impact on the performance of the road network and potential treatments over the medium to long term. Examples of this §§ whether any areas in Victoria are susceptible are road condition monitoring and data on road to salt related pavement blistering or salinity closure duration, frequency and location related impacts zz ensuring that climate adaptation is considered §§ changes in the distribution of flora and fauna in relation to the development and updating §§ alternative water sources of other VicRoads strategies, for example the VicRoads Asset Strategy and the VicRoads Rural §§ geotechnical risk (including coastal erosion) Arterial Roads Strategy zz continuing to review potential risks and zz standardising the integration of adaptation data responses as a result of: layers such as sea level rise and storm surge §§ economic changes namely population into network planning activities to identify likely growth and urban planning. risks early in the development of an alignment. This could have the benefit of allowing climate §§ changes in the road network and innovations risks to be avoided rather than including costly in smart car technologies, driverless cars, adaptation measures at a future point in time smart cities and other supporting infrastructure §§ understanding community expectations zz embedding a level of awareness in VicRoads across the organisation. This will assist with respect to level of service and how the employees to understand the likely types level of impacts acceptable for road users of impacts, understanding how VicRoads is and freight will increase or decrease as more addressing these risks and also assist employees impacts occur in discussions with other stakeholders around zz reviewing financial implications including: adaptation. Importantly this will also assist §§ how adaptation will be funded, given employees required to assist in gathering data the likely broad impacts on society and and information to understand why they are infrastructure resulting in competing needs undertaking these actions for the same funding. zz constantly reviewing risk and responses as §§ implications for insurance and whether climate change projections are refined insurance policies could be changed to incentivise adaptation or penalise a lack of adaptation
Summary of Organisational Responses A number of actions will need further investigation including; §§ Ensuring appropriate existing sources of information are captured to provide baseline and contextual information for climate change impacts and to inform adaptation §§ Developing a level of internal awareness of climate change risks to VicRoads and how this is being addressed. §§ Ensuring that climate adaptation is integrated as appropriate into other new or revised VicRoads strategies to ensure appropriate consideration of responses §§ Developing and integrating appropriate climate risk data layers to ensure a consistent evaluation of forecast climate change impacts into strategic network planning activities
CLIMATE CHANGE RISK ASSESSMENT 37 8. Next Steps Given the timeframes of projected climate change impacts, VicRoads has time to revise its A climate resistant road network will reduce climate change adaptation responses as updated the physical vulnerability of critical infrastructure information becomes available. The exceptions are through the retrofitting and rehabilitation of existing the need for early integration of climate change infrastructure including associated drainage and implications into the selection of road corridors flood mitigation systems in order to strengthen its and the design of bridges given their long design resilience to natural hazards and the anticipated life and the difficulty in adapting existing bridges. In impacts of climate change. addition, these climate change impacts, including Developing resilience and building adaptive those beyond 2100 are important to understand as capacity of road networks, especially in regards part of current strategic network planning activities. to climate change, is integral to accessing and The creation of road reservations (such as the E6 delivering critical infrastructure. Over time, transport corridor) can be in place for a significant state and national infrastructure has become amount of time before construction. It is therefore increasingly interconnected and interdependent, important to consider climate change impacts as with a particular reliance upon transportation part of the creation of road reservations, especially systems, so failures or loss of transport services along coast so road networks are developed away will have subsequent effects. Any damage to from areas of risk. road infrastructure from climate change and The projected climatic changes will almost certainly extreme weather can have an impact on local have a significant impact on the appraisal, design, communities and businesses. Restrictions on construction, operation and maintenance of the movement of people, goods and supplies road infrastructure. The risk assessment process around a region will almost certainly lead to described herein enables climate change to be impacts upon the local economy, environment regarded as a strategic risk to which requires and the health and wellbeing of residents. Given consideration and adoption of adaptation principles these interdependencies within and between to address the climate-induced impacts. infrastructure sectors, it is essential that these interdependencies are both understood and VicRoads recognises that for adaptation measures managed to improve the resilience of infrastructure to be successful, it will need to incorporate to future climate change. involvement from a number of stakeholders such as local councils, catchment authorities and Ongoing monitoring and review of climate other government departments who would likely change risk, vulnerabilities and the effectiveness of be affected or who would be involved in a co- adaptation response is essential. According to the ordinated response. Not only will this facilitate early United Nations Framework Convention on Climate engagement but should minimise any duplication Change (UNFCC). of effort or maladaptation. Forward planning will enable VicRoads in partnership with its key stakeholders - to make investment decisions at the Monitoring and evaluation of projects, policies right time, making sure that it continues to provide and programmes forms an important part of the levels of service that its stakeholders and the adaptation process. Ultimately, successful network users expect, both now and in the future. adaptation will be measured by how well different measures contribute to effectively reducing vulnerability and building resilience. Lessons learned, good practices, gaps and needs identified during the monitoring and evaluation of going and completed projects, policies and programme will inform future measures, creating an iterative and evolutionary adaptation process.
38 Glossary IFD or Intensity, Frequency, Duration is a commonly AEP used tool to graphically represent the projected Annual Exceedence Probability is the probability of rainfall volumes for a rainfall event with a given volume of rainfall being exceeded in year combination of rainfall intensity, event frequency (i.e. a 20% AEP of 100mm is a probability of 20% and event duration. that the annual rainfall will exceed 100mm). 100 divided by the AEP will give a rough indication of IPCC the length of time between annual rainfalls of a The Intergovernmental Panel on Climate Change given volume (i.e. 100/20 = 5 years between annual is a global scientific body established by the United rainfall volumes of 100mm). Nations. It produced reports that support international efforts to limit and manage climate change Asphalt a graded mixture of stones and finer particles LED bound together with bitumen. Light Emitting Diode, a technology used to provide illumination (currently used primarily for traffic BOM lights, but may be extended to public street lighting) Bureau of Meteorology that has a long service life and low operating costs CCTV due to low power consumption VicRoads maintains a network of Closed Circuit Main Road or Arterial Road Television Cameras at strategic locations on the VicRoads is the co-ordinating road authority for road network to help monitor and manage traffic management of the declared freeways and arterial flow conditions roads listed in the Road Management Act 2004, CSIRO but excludes local roads under the care of local Commonwealth Scientific and Industrial Research government, forest roads under the care of the Organisation is an Australian Federal agency Department of Environment and Primary Industry performing scientific research and Toll Roads. DEPI Roadside is the former Department of Environment and generally refers to the area between the outer Primary Industry, a Victorian State Government edge of shoulder or kerbing and the road reserve Department which managed Coasts & Marine, boundary that is usually grassed or planted. It Conservation & Environment, Fire & Other includes pedestrian and cycle paths. Emergencies, Forests, Land Management, Parks Road Pavement & Reserves, Plants & Animals, Property Titles & Road Pavement Layers are made up of compacted Maps, Recreation & Tourism and Water layers of structural fill and crushed rock. The DEDJTR purpose of the road pavement is to carry wheel is the Department of Economic Development, loads without deforming and causing damage to Jobs, Transport and Resources, a Victorian State the surface layers. Government Department. Road Surface DELWP The majority of main roads in Victoria have a is the Department of Environment, Land, Water waterproof layer of surface material to provide a and Planning, a Victorian State Government low maintenance all-weather riding surface and Department. protect the underlying road pavement material from ingress of free water. Typically, this surface is DSE a sprayed seal in rural areas and an asphalt layer in Department of Sustainability and Environment a more heavily trafficked urban areas. former Victorian State Government Department, which managed water resources, climate change, Sprayed Seal bushfires, public land, forests and ecosystems. It is a surface of stones embedded in a layer of bitumen. now incorporated within DELWP.
CLIMATE CHANGE RISK ASSESSMENT 39 Bibliography ARRB. (2013). Guide to Road Design, Part 5: Drainage DEPI a. (2013). Future Coasts Program. Retrieved from - General and Hydrological Considerations. Sydney: Building a LCimate Resilient Victoria: http://www. Austroads. climatechange.vic.gov.au/climate-science-and-data/ future-coasts Australian Plants Society. (2011). Drought Tolerant Plants. Retrieved from Australian Plants Society - Victoria: http:// DEPI b. (2013). Victorian Coastal Innundation Dataset. www.apsvic.org.au/plant_nowater_tolerant.html, Retrieved from Building a Climate Resilient Victoria: http:// www.climatechange.vic.gov.au/climate-science-and-data/ BOM. (n.d.). Ultraviolet (UV) Index Forecast. Retrieved future-coasts/victorian-coastal-inundation-dataset November 13, 2014, from Bureau of Meteorology: http:// www.bom.gov.au/australia/uv/ DSE. (2008 a). Climate Change in Corangamite Region. Melbourne: Victorian Government Department of City of Melbourne. (2015). Exploring Melbourne’s Sustainability and Environment. Urban Forest. Retrieved from City of Melbourne Urban Forest Visual: http://melbourneurbanforestvisual.com. DSE. (2008 b). Climate Change in East Gippsland Region. au/#mapexplore Melbourne: Victorian Government Department of Sustainability and Environment. Commissioner for Environmental Sustainability Victoria. (2012). Foundation Paper One, Climate Change, Victoria: DSE. (2008 c). Climate Change in Port Phillip and the science, our people and out state of play. Victoria: Westernport. Melbourne: Victorian Government Commissioner for Environmental Sustainability. Department of Sustainability and Environment. CSIRO. (2007 a). Climate Change in Australia. Retrieved DSE. (2008 d). Climate Change in the Coulburn Broken November 13, 2014, from Climate Change in Australia: Region. Melbourne: Victorian Government Department of http://www.climatechangeinaustralia.gov.au/index.php Sustainability and Environment. CSIRO. (2007 b). Bushfire Weather in Southeast Australia: DSE. (2008 e). Climate Change in the Glenelg Hopkins Recent Trends and Projected Climate Change Impacts. Region. Melbourne: Victorian Government Department of Melbourne: Bushfire CRC. Sustainability and Environment. CSIRO. (2007 c). Climate Change in Australia. Retrieved DSE. (2008 f). Climate Change in the Mallee Region. November 13, 2014, from Climate Change in Australia: Melbourne: Victorian Government Department of http://www.climatechangeinaustralia.gov.au/index.php Sustainability and Environment. CSIRO. (2007 d). Climate Change in Australia Technical DSE. (2008 g). Climate Change in the North Central Report. Retrieved November 13, 2014, from Climate Region. Melbourne: Victorian Government Department of Change in Australia: http://www.climatechangeinaustralia. Sustainability and Environment. gov.au/documents/resources/TR_Web_Ch5i.pdf DSE. (2008 h). Climate Change in the North East Region. CSIRO. (2007 e). Infrastructure and Climate Change Risk Melbourne: Victorian Government Department of Assessment for Victoria. Melbourne: Victorian Government. Sustainability and Environment. CSIRO. (2014). State of the Climate 2014. Canberra: DSE. (2008 i). Climate Change in the West Gippsland Commonwealth of Australia. Region. Melbourne: Victorian Government Department of Sustainability and Environment. DCCEE. (2011). Climate Change Risks to Coastal Buildings and Infrastructure. Canberra: Department of Climate DSE. (2008 j). Climate Change in the Wimmera Region. Change and Energy Efficiency. Melbourne: Victorian Government Department of Sustainability and Environment. Department of Sustainability and Environment. (2012). Victorian Coastal Hazard Guide. Melbourne: Victorian DSE. (2013). Victorian Climate Change Plan. Government. Melbourne: Victorian Government. Retrieved from http://www.climatechange.vic.gov.au/__data/assets/ DEPI. (2014). Victorian Resources Online. Retrieved from pdf_file/0006/158640/4493_DSE_Climate_Change_ Department of Environment and Primary Industries: http:// Adaptation_Plan_WEB.pdf vro.depi.vic.gov.au/dpi/vro/map_documents.nsf/pages/ vic_prim_prod_rainfall_50 EEA. (2014). Adaptation of transport to climate change in Europe. Luxembourg: European Environmentla Agency.
40 Global Carbon Project. (2014). Global Carbon Budget - Stocker, T. F., Qin, D., Platter, G. K., Tignor, M., Allen, Data. Retrieved from Global Carbon Project: http://www. S. K., Boschung, J., . . . Midgley, P. M. (2013). Climate globalcarbonproject.org/carbonbudget/14/files/Global_ Change 2013: The Physical Science Basis. Contribution Carbon_Budget_2014_v1.0_final21Sept2014.xlsx of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, Kendal, D., & McDonnell, M. J. (2014). Potential United Kingdom and New York, NY, USA: Cambridge Consequences for Management, Urban Ecosystems, University Press. and the Urban Public: Adapting Urban Forests to Climate Change. Citygreen #8, 130-137. UK Highways Agency. (2011). Climate Change Risk Assessment. Dorking: UK Highways Agency. Kendall, D. (2011). Potential effects of climate change on Melbourne’s street trees and some implications for human VAGO. (2013). Implementation of the Government Risk and non-human animals. Retrieved from State of Australian Management Framework. Melbourne: Victorian Auditor- Cities National Conference: http://soac.fbe.unsw.edu. General’s Office. au/2011/papers/SOAC2011_0112_final.pdf VicRoads. (2010). Sustainaiblity and Climate Change Maunsell. (2008). City of Melbourne Climate Change Strategy (1.0 ed.). Melbourne: VicRoads. Retrieved Adaptation Strategy. Melbourne: City of Melbourne. May 2014, from http://www.vicroads.vic.gov.au/NR/ rdonlyres/4DB4B3E3-E5E9-4DD6-8F15-9B7EBB33D90C/0/ Melillo, J. M., Richmond, T. C., & Yohe, G. W. (2014). Climate SustainabilityandClimateChangeStrategy20102015.pdf Change Impacts in the United States: The Third Climate Assessment. Washington DC: U.S. Global Research Program. VicRoads. (2010, September). Sustainaiblity and Climate Change Strategy (1.0 ed.). Melbourne: VicRoads. Retrieved Nicholson, L. (2014). Melbourne City Council to replace May 2014, from http://www.vicroads.vic.gov.au/NR/ Melbourne’s trees with exotic species. Retrieved from The rdonlyres/4DB4B3E3-E5E9-4DD6-8F15-9B7EBB33D90C/0/ Age: http://www.theage.com.au/victoria/melbourne-city- SustainabilityandClimateChangeStrategy20102015.pdf council-to-replace-melbournes-trees-with-exotic-species- 20140530-399sw.html Victorian Planning Provisions Section 10 Clause 13. (2014, October 2). Retrieved October 30, 2014, from Victorian OzCoasts. (2013). OzCoasts. Retrieved from GeoScience Planning Provisions: http://planningschemes.dpcd.vic.gov. Australia: http://www.ozcoasts.gov.au/coastal/smartline.jsp au/schemes/vpps/13_SPPF.pdf Pedruco, P., & Watkinson, R. (2010). The Impacts of Climate Change on Urban Flooding in the Melbourne Area Using Existing Flood Models. Melbourne: BMT WBM. Powers, N., & Rapattoni, F. (2014). Review of AS5100.1 - Scope and General Principles. Retrieved from ARRB: http:// www.arrb.com.au/admin/file/content128/c6/11775_NP_ Review%20of%20the%20Bridge%20Design%20Code%20 (AS5100)%20Part%201%20-%20Scope%20and%20 General%20Principles.pdf SKM. (2012). Sinclair Knight Mertz - Coastal climate change vulnerability and adaptation. Melbourne: Great Ocean Road Coastal Committee. Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., . . . Miller, M. L. (2007). Climate Change 2007: The Physical Science Basis. Contribution of Working Group 1 to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge United Kingdom and New Your, USA: Cambridge University Press.
CLIMATE CHANGE RISK ASSESSMENT 41 Appendices Appendix 1 : Case Studies Phillip Island Road – Climate Adaptation Phillip Island Road is the only means of road access to San Remo and Phillip Island, which has some of Victoria’s iconic tourist locations and sporting events, as well as a resident population of over 9000. In September 2012 an erosion event removed about 3 metres of foreshore at San Remo adjacent to the Phillip Island Rd, with the road now within 3-4 metres of the edge of the cliff and at risk of collapse. The cliff in this vicinity is about 11 metres in height. The adaption measure selected was a revetment, which is a sloping structure designed to protect an area and absorb the energy of incoming water. The revetment was designed to be a non-overtopping DELWP seawall with a lifespan of 100 years. The designed rock revetment crest level of 3.91m AHD has been calculated using the highest astronomical tide for Stony Point (1.65m), the 1 in 100 storm surge level (0.82m), sea level rise at 2100 (0.8m) and the wave run up for rock armoured slopes (2:1) with an impermeable core (0.64m). That is 1.65 + 0.82 + 0.8 + 0.64 = 3.91. In this way, the design life of the revetment (and the stability of the slope behind it) is maximised while mitigating the potential impacts of climate change. This provided an opportunity to work together and deliver a positive outcome for both parties and the community, and is planned to link with other existing and future tracks in this area to enhance
the foreshore experience DELWP
42 Great Ocean Road – Adaptation Measure As part of current Great Ocean Road maintenance works, drainage near approximately 1.5 kilometres south west of Wye River, was identified as needing replacement, due to age and damage as stormwater was gathering on the upstream side and infiltrating the embankment creating cavities and weakening the strength of the embankment. The location prior to adaptation is shown in the photo below. Whilst it was seen that the existing DELWP drainage was undersize to requirements, the likely future drainage needs were considered, including the potential for more intense rainfall events as a result of climate change. After consideration of likely parameters, with a local projected rainfall projected to remain at 900-1100mm per year in 2050 (DEPI, 2014) and an increased rainfall intensity of 6.5 percent in 2070, it was decided to replace the existing 600mm diameter drain was replaced with two 1.5metre diameter drains, which are shown in photo below.
This will ensure that the culvert can deal with DELWP projected volumes and increases to projected rainfall intensities. Additional works included replacing the concrete end walls, the existing fill material, install kerb and channel and beaching to control embankment erosion and installation of guard fence. The completed works are shown below. Given the iconic nature and high proportion of tourist traffic, the main challenge in implementing the works was in communicating the closures of the road and ensuring it occurred during a time with lower projected traffic volumes. DELWP
CLIMATE CHANGE RISK ASSESSMENT 43