1.2 Respond to a changing climate
Climate change will result in more frequent and intense bushfires, heatwaves, droughts, extreme rainfall events and coastal inundation in coming decades.1 Victorians are already seeing climate change affect society, the economy and the environment, most recently in extreme droughts, floods, and catastrophic bushfires. It also affects Victoria’s First Nations peoples, whose traditional lands and waters are heavily impacted. These impacts can be broad and widespread for the whole community. For example, a heatwave can increase demands on the health system, disrupt public transport, and cause a loss of power supply.2 Flooding from stormwater can displace people from their homes and damage buildings.3 Climate change is already increasing the death rate from warm season heat-related deaths on every continent.4
Infrastructure contributes to climate change by generating greenhouse gas emissions from its direct operations, the materials used in its construction, and the activities it enables.5 For example, transport emissions have increased more than 60% since 1990, accounting for around one-fifth of total emissions in 2019.6 The infrastructure Victoria builds today can lock in future emissions,7 especially without a plan to convert it to zero emissions technology later.
New infrastructure must also function in a warmer, drier climate and be resilient to more extreme weather. These changes affect infrastructure’s performance under extreme conditions, and the demand for it.8 Changing operating conditions may require changes to the location, design, construction, operation, maintenance and upgrade of infrastructure, and in some cases reassessing assets’ continued viability. The infrastructure decisions Victoria makes now will affect its climate change response in coming decades and constrain future choices.
The last comprehensive assessment of climate change risk to Victoria’s infrastructure was produced in 2007.9 Evidence produced since means the climate consequences for infrastructure are now better understood and can be better incorporated into infrastructure and built environment frameworks.10 For example, using the most up to date information available on the likely future climate11 would support building homes accordingly. Shorter infrastructure life or planning for major future retrofits may need to be considered if Victoria is to achieve its net zero emissions goal.
Climate change introduces new risks
Victorian average temperatures have increased 1.2°C since official records began in 1910,12 with temperatures tracking towards the higher range of emissions pathways.13
The mean sea level for Melbourne has risen 2 millimetres each year since 1966.14 Victoria has experienced an increase in dangerous fire weather and length of fire seasons since the 1950s.15
By the 2050s, under a high emissions scenario and compared with the period of 1986–2005, Victoria could experience:16
Even with strong global emissions reductions, the effects of this warmer, drier future climate will vary across regions. For instance, projected changes in temperature are higher inland compared with coastal areas.17 Summer rainfall has increased in the north, but winter rainfall has declined statewide,18 with winter rainfall tracking towards the higher emissions pathway19 and average annual rainfall declining overall.
While average changes might seem small, they reflect significant extremes of heat and rainfall that can be very challenging for people, infrastructure and the environment. At the time of writing, 34 out of Victoria’s 79 local councils have recognised, acknowledged or declared a climate emergency.20
Climate change means less water in storages
Water infrastructure and supply are acutely vulnerable to climate change impacts. Figure 5 shows that rainfall in Victoria is projected to decrease. A warmer, drier climate means less rainfall flowing into Victoria’s rivers and dams, putting more pressure on urban water supplies. Water infrastructure will also be affected by more frequent extreme rainfall events, movement and changes in groundwater, and higher average temperatures with lower average rainfall. This suggests higher risks of water shortages and drainage and sewerage damage from stormwater flooding.21 More frequent and intense bushfires also risk damage to catchments and water storages, from ash and debris contaminating the water supply.22
Water resource and supply planning23 incorporates climate change projections and scenarios, and increased monitoring, to better understand potential future water availability.24 Combined with high population growth, water shortages could emerge in Melbourne as soon as 202825 under a high climate change scenario, with even a mid-range scenario seeing shortages by 2043.26 Shortfalls may occur earlier in some regional areas, including as early as 2025 in areas serviced by Coliban Water
which includes Bendigo27 and 2031 in areas serviced by Greater Western Water which includes Bacchus Marsh, Melton, Sunbury and parts of the Macedon Ranges.28 Drought will continue to be a feature of Victoria’s climate and is acutely felt by regional Victorians and the agricultural sector. Agriculture is Victoria’s largest water user,29 and a significant regional employer.30
Climate change poses a risk to agriculture in every Victorian region.31 For example, the agriculture sector incurs almost half of the total economic impacts from a severe heatwave.32 The Victorian Government will invest $20 million from 2021–22 to 2025–26 to accelerate Victoria’s agriculture sector response to a changing climate.33
Climate change is increasing the intensity and frequency of hot days and heatwaves, exacerbating any drought conditions. The severity of the millennium drought has been linked to human-induced climate change,34 and time spent in drought is projected to increase across southern Australia.35 During droughts, the warmer, drier weather increases water demand and reduces water storages. Victoria will need to increase resilience and prepare for longer, more intense future droughts
Victoria will be at risk from more frequent and intense bushfires
Victoria is one of the most fire prone places on Earth.36 The 2009 Black Saturday bushfires and the 2019–20 summer bushfires in East Gippsland and the state’s north-east resulted in significant loss of life, property, wildlife, and natural ecosystems. More intense fire behaviour, increased fire activity, longer and earlier fire seasons, and droughts are clearly linked to climate change.37 In the 2019–20 Victorian summer bushfires, more than 300 homes were destroyed and 1.2 million hectares of land was burnt – making it the largest bushfire since 1939.38 It affected at least 60% of the state’s national parks and nature reserves,39 impacting significant environmental assets and biodiversity.
The bushfires revealed the region’s vulnerabilities, with communities and visitors cut off and in direct danger, including more than a thousand evacuated by sea from Mallacoota.
Bushfires highlight risks to electricity, telecommunications, water supply and transport infrastructure, among other vulnerabilities. Without access to critical phone and internet connections for emergency management information, people are at greater risk,40 including local residents, and holidaymakers who are less likely to have a bushfire plan.
Recommendations to respond to climate change
Infrastructure Victoria makes the following recommendations to help respond to a changing climate. These are further complemented by recommendations to navigate the energy transition (see section 1.1), improve urban open space and tree canopy (see recommendations 37 and 77), build resilience to emergencies (see section 1.3), and respond to climate risks in regional areas (see section 4.3). Many more of our recommendations in other sections have climate benefits, including improvements to land use planning and transport networks.