Better understand known and potential hazards

Rebuilding houses, suburbs and towns requires planning for known or potential risks to ensure that buildings and infrastructure can respond to the real threat of more extreme weather events caused by climate change.

As a starting point, a more comprehensive understanding of future risk and the potential frequency of hazardous events is essential. Identifying the location of these risks through engagement with relevant professionals and technicians, research and data analysis and spatial mapping to more precisely identify higher risk locations is essential to inform this understanding.

In the past, planning for development has considered natural hazard risks based on historical patterns of flooding, bushfire etc. With the expected and ongoing impacts of climate change and the increasing severity and frequency of natural disasters, it is important that new development occurs in areas least likely to be impacted by future extreme weather events and/or designed to better manage or respond to potential natural disasters if, or when, they occur.

In established areas where recent disasters including flooding, bushfires, coastal erosion and drought have occurred, the opportunity exists to reimagine future development and rebuild more resilient, energy efficient, safe and secure settlements.

Design and plan land use for known or potential hazards

Better and more informed decisions on ‘retrofitting’ or protecting existing settlements, or on the future location and design of settlements will be enabled by enhanced knowledge of risk and potential hazards.

Protective options include perimeter roads and managing adjacent land surrounding settlements, with the provision of safety bunkers for communities or housing in high risk and/or remote areas. Perimeter roads around settlements can be beneficial as a fire break but also provide access for emergency vehicles and escape routes for local residents where they might otherwise be reliant on a single road, in and out of small and remote settlements. Ensuring that sensitive land uses such as aged care facilities and child care are outside of higher hazard areas is especially important for vulnerable people who are not independently mobile.

Consolidation and intensification of development should only occur in areas where the environmental values will not be significantly impacted by protection measures and away from potentially hazardous urban edges including coastal erosion zones and high bushfire hazard areas.

In some areas resettlement may need to be contemplated. While individual households may choose to relocate, due to the trauma experienced or high costs of rebuilding, there is also the option to consider this at a community level, based on known risks. One option known as managed retreat, has already occurred in towns such as Grantham in Queensland (west of Brisbane) that was severely affected by the 2011 floods. In this example, an Australia-first plan ‘Strengthening Grantham’ was implemented. This plan offered residents of low-lying flood impacted properties the opportunity to relocate to land outside of the flood plain. Residents who took up the offer to swap lots of land were paid to build their new homes with insurance payouts, backed by special grants from the Premier's Flood Appeal. ‘Strengthening Grantham’ was facilitated by a compressed planning process that would typically take two to three years, being undertaken in four months and included visioning and design option workshops with local residents, to identify future directions and desired outcomes for the community.

In other locations, managed retreat may not be necessary or desirable. In areas with a lower frequency or severity of extreme weather events, the alternative to build back better and more resilient communities may be preferable. Equally, in larger, more established settlements the choice may be to build back as more resilient, adaptive and prepared communities, with the option to consider a long term system of planned retreat.

Rebuilding better buildings

Ensuring that new and existing buildings respond to expected local climate conditions, means that buildings and their occupants can better withstand the extremes of heat and cold, as well as high wind, fire and flood. Improved building standards have already meant that in some areas, new homes are much more likely to survive bushfires through decreasing the risk of ember attack infiltrating the building envelope.

In some areas, bushfire hazard overlays may need to be extended or Bushfire Attack Level (BAL) ratings increased. Currently in Victoria, for example, landowners in designated Bushfire Prone Areas are required to build to a minimum Bushfire Attack Level (BAL) of 12.5, which ensures that a building can withstand ember attack and exposure to a level of radiant heat up to and including 12.5 kW/m2. Higher BALs, such as BAL 40, mean that buildings can withstand burning debris, windborne embers and radiant heat up to and including 40kW/M2, while a BAL of Flame Zone can withstand the radiant heat exposure of flames.

More resilient infrastructure

Decentralised energy and water systems

More resilient infrastructure can be achieved through built in redundancy, involving the duplication of critical components or functions of a system to increasing system reliability.

This can include creating stand-alone decentralised energy and water supply systems that do not depend on centralised networks to remain operational. The World Energy Issues Monitor (2019) identifies that in Australia one of the most pressing issues for our energy sector is decentralised systems. For local communities and homes this could include solar power, battery storage, and microgrids that can be deployed to provide backup power in the event of an outage, or used as the primary source of energy, particularly in more remote areas. This has the added advantage of reducing emissions where these power sources are not based on fossil fuels.

Reliable energy supply

Decentralised energy infrastructure will also increase reliability and resilience in the event of ‘upstream’ system failure or shutdowns. Undergrounding electric and natural gas distribution infrastructure and ensuring it is outside of flood zones, can also provide more resilient energy distribution networks that can remain intact in flood, bushfire and high wind events such as cyclones.

Reliable water supply

Water supply is also vital, particularly in times of drought and bushfire emergencies. Ensuring on-site independent access to water supply is critical. In the event of a bushfire, water mains pressure may drop, resulting in water not flowing from hoses and taps at the time it is most needed. Having an on-site water supply through tanks, ponds or dams, together with a pump that can function independent of the electricity grid, ensures not only that water is available, but that it can be used, even when central electricity supplies are not operational.

Provision of on-site water retention, not only at an individual property level, but also at a suburb or district level, can not only provide water reservoirs and buffers in emergencies but also enhance ecological diversity. Water sensitive urban design measures can ensure water is naturally filtered and cleaned (bio-filtration) and also support natural habitat for native flora and fauna. Such systems can also contribute to reduced water consumption which will be critical as rainfall in central storage areas declines or is less reliable.

Sustainable and resilient transport options

Ensuring that there are different transport options available, including transport systems that are not entirely dependent on imported fuel reserves, can become particularly important in periods of local emergency or weather hazard. Cars fueled by petrol and diesel rely on fuel being imported and trucked to individual communities where it is then distributed through the petrol bowser. In the case of extreme events, this system can quickly break down. The recent closure of the Princes and Kings Highways during the bushfires on the south coast of NSW being a case in point. Alternative options include electric vehicles powered by renewable energy sources, with local distribution and storage. There is a need for an acceleration in our uptake of electric vehicles as it is a practical way for transitioning to a clean economy with significant related benefits.