Natural hazards

Background

Natural hazards are natural processes that have the potential to significantly harm people, properties, communities, industries and infrastructure. While natural hazards cannot be prevented, they can be anticipated and planned for. Land use planning is forward-looking, with a role in guiding strategic use of land and managing new development in areas exposed to natural hazards by avoiding the hazard, reducing the impact of the hazard on the use or development, and ensuring that the use or development does not contribute to increasing the impact of the hazard on neighbouring uses. In Tasmania the following natural hazards are considered in the planning system:

• flood (riverine and coastal)
• coastal erosion
• landslip
• bushfire.

Heatwaves, wind and intense rainfall, while significant natural hazards, are addressed through construction standards under the building system or through stormwater systems.

How is this managed within the planning system?

The objectives of the Resource Management and Planning System (RMPS) and the Land Use Planning and Approvals Act 1993 (LUPAA) provide the overarching framework for the management of natural hazards in the planning system. The RMPS objectives focus on providing for the fair, orderly and sustainable development of land, which flows into all parts of the planning system and LUPAA. The objectives also aim to ensure a pleasant, efficient and safe environment for working, living and recreation.

Generally, we plan to minimise the community’s vulnerability to natural hazards at a strategic planning level first. This provides the best opportunity for intervention in the planning system by identifying areas susceptible to natural hazards and avoiding locating development in these areas. This is generally achieved through planning for settlement growth in appropriate locations within regional land use strategies and local strategic plans and applying appropriate zoning to land in the planning scheme.

The draft Tasmanian Planning Policies (TPPs) and the three current regional land use strategies all have high level policies and strategies for managing natural hazards. These are implemented through the Tasmanian Planning Scheme (TPS) by the application of appropriate zoning and planning requirements for managing impacts.

Flooding and coastal erosion

Riverine and coastal flooding are natural events that may occur as a result of storms, or in the case of coastal flooding, due to storm surges, tides and sea level rise. Coastal erosion involves the wearing away of coastal areas by water, wind and general weather conditions, or as a result of long-term changes to coastal land by sea level rise.

The natural pattern of significant storm events causing flooding is changing, with increasing numbers of short-duration intense rainfall events occurring as a result of climate change. Sea level rise is likely to increase the frequency and severity of coastal flooding and erosion events.

Historically, the development of communities in Tasmania has been centred on available flat land along rivers or estuaries. In some locations levee systems have been required to manage the impact of flooding, while in other locations, communities were built to accommodate historical flood patterns. With the change in storm patterns and flooding due to climate change, land use planning can support communities to be prepared.

The TPS includes codes for riverine flooding, coastal erosion, and coastal inundation hazards. These codes operate alongside and are supported by the building system under the Building Act 2016.

The two coastal hazard codes include planning maps to identify areas potentially vulnerable to coastal erosion and inundation from now until 2100. The planning maps have different hazard bands for the susceptibility of the land to that hazard and take into account the predicted impacts of climate change. The riverine flooding hazard code is currently applied through local council flood mapping and known flood-prone areas.

Most building work in urban areas is not considered under the two coastal hazard codes. Impacts on building work are generally considered through the building system. The codes generally only manage impacts relating to:

• defined critical, hazardous and vulnerable uses
• use and development in the higher hazard bands
• coastal protection works, like sea walls
• subdivision.

Please see the Coastal Hazard Information sheet for more information. The State Planning Office also has other coastal hazard information including a fact sheet on future coastal refugia, guidance on coastal erosion investigation areas and a template for a coastal hazards report.

Landslip

Landslip is the mass movement of soil or rocks downslope. Landslip becomes a hazard when development is undertaken with limited consideration of landslip in susceptible areas, or following an event such as significant rainfall.

The TPS includes a code for landslip hazard. The Code manages the impacts of landslips for new use and development through the landslip planning hazard maps, alongside the building system, under the Building Act 2016. The landslip planning hazard maps include an assessment of the susceptibility of slopes based on geology, soil types, and steepness, and if the land has been or is a landslip. The planning maps have different hazard bands for the susceptibility of the land to landslip. These bands set different requirements based on the levels of risk in each.

Most building work is not considered under the Landslip Hazard Code. Impacts on building work are mainly considered through the building system. The Code generally only manages impacts relating to:

• defined critical, hazardous and vulnerable uses
• use and development in the higher hazard bands
• development involving ‘significant works’, such as excavation or land filling and the discharging of wastewater and stormwater
• subdivision.

Mineral Resources Tasmania has detailed information about land slip on their website, including fact sheets and FAQs.

Bushfire

Bushfires can generally be described as unplanned vegetation fires. While bushfires are a natural and essential part of the Australian environment, uncontrolled bushfires can significantly impact communities. Bushfires can be started by natural causes, such as lightning strikes, by malfunction of electricity infrastructure, or by people. Weather and vegetation conditions play an important part with climate change likely to increase the frequency and severity of bushfire events.

Following the Victorian Black Saturday Bushfires in 2009, the Tasmanian Government implemented the Victorian Bushfires Royal Commission findings. These include consistent statewide planning and building controls to ensure that all developments have:

• a minimum separation from the bushland giving an area for a firefighter to work in
• the provision of water
• vehicular access, and
• a minimum construction standard for all new developments.

The TPS includes a code for bushfire hazard. The Code manages the impacts of bushfires for new use and development through the bushfire planning hazard maps alongside the building system under the Building Act 2016.

Most building work is not considered under the Bushfire-Prone Areas Code. Impacts on building work are mainly considered through the building system. The Code generally only manages impacts relating to:

• defined hazardous and vulnerable uses
• subdivision.

Planning initiatives

Mitigating Natural Hazards through Land Use Planning

In 2011, the Department of Premier and Cabinet established a project to develop a framework for the mitigation of risks from natural hazards through land use planning and building controls. The framework led to comprehensive analysis, guides and reports on coastal and landslip hazards. Coastal hazard and landslip planning maps and policies implemented through the TPS and the building system were also informed by the framework.

Please see Mitigating Natural Hazards through Land Use Planning for more information.

Draft Tasmanian Planning Policies

The draft Tasmanian Planning Policies have a policy relating to natural (environmental) hazards. It promotes addressing hazards early in the planning process. This will assist in protecting life and property, reduce the financial and emotional cost to the community and decrease the burden for emergency management. The draft policy applies the following nine principles to drive the planning policy response to natural hazards:

• prioritise the protection of human life
• support disaster resilience of communities
• identify and map the environmental hazard
• avoid designating land for incompatible use or development in hazard prone areas
• ensure the use and development (including intensification of existing ones) does not increase the risk of environmental or potential harm
• ensure hazard mitigation measures are applied to reduce that risk to a tolerable level
• select hazard mitigation measures which minimise the impacts on other identified values where possible
• ensure regulation of use and development reflects the level of exposure to the risk of harm caused by the hazard

Once finalised, the TPPs will be implemented through revisions to the regional land use strategies and the SPPs in the TPS. All amendments to the council's Local Provisions Schedules in the TPS will need to be consistent with the TPPs.

The three existing regional land use strategies include strategies for managing natural hazards. The strategies guide where growth occurs in our settlements. They aim for growth to occur in appropriate locations and guide the application of zones in the TPS. These currently regional strategies are subject to review which will include application of the TPPs at a regional scale.

Tasmanian Planning Scheme

The introduction of the TPS delivered consistent planning requirements across a range of natural hazards. This included the following natural hazard codes:

• C10.0 Coastal Erosion Hazard Code
• C11.0 Coastal Inundation Hazard Code
• C12.0 Flood-Prone Areas Hazard Code
• C13.0 Bushfire-Prone Areas Code
• C15.0 Landslip Hazard Code

Consistent statewide overlay maps have been delivered for the two coastal hazard codes: Bushfire-Prone Areas Hazard Code and Landslip Hazard Code. Consistent statewide mapping of riverine flooding for the Flood-Prone Areas Code is currently under preparation through the Tasmanian Strategic Flood Mapping project.

The State Planning Provisions (SPPs) in the TPS are being reviewed following their introduction in 2017. The SPPs are reviewed every 5 years to ensure they remain relevant and to implement improvements.

A review of the natural hazard codes has been identified as a key project as part of the review of the SPPs, along with implementation of updated landslip hazard mapping and the introduction of statewide riverine flood mapping.

If you need an introduction to how overlays, zones and codes work, you can visit Getting Started and Tasmanian Planning Scheme.

Tasmanian Strategic Flood Mapping Project

The Tasmanian Strategic Flood Mapping project was established following the severe floods in 2016. The project is jointly funded by the Australian and Tasmanian governments and includes developing a flood risk assessment and land use planning and building controls.

The project will deliver statewide flood-prone area mapping and a revised Flood-Prone Areas Hazard Code in the TPS. This will include greater integration with the Coastal Inundation Hazard Code and the building system.

Draft Tasmanian Planning Policies and review of regional land use strategies

The draft TPPs have a policy relating to natural (environmental) hazards. It promotes addressing hazards early in the planning process. This will assist in protecting life and property, reduce the financial and emotional cost to the community and decrease the burden for emergency management. The policy applies the following 9 principles to drive the planning policy response to environmental hazards:

• Prioritise the protection of human life.
• Support disaster resilience of communities.
• Identify and map the environmental hazard.
• Avoid designating land for incompatible use or development in hazard prone areas.
• Ensure use and development, including intensification of existing use and development, does not increase the risk of environmental hazards or the potential harm.
• Ensure hazard mitigation measures are applied to reduce that risk to a tolerable level.
• Select hazard mitigation measures which minimise the impacts on other identified values where possible.
• Ensure regulation of use and development reflects the level of exposure to the risk of harm caused by the environmental hazard.

Once finalised, the TPPs will be implemented through revisions to the regional land use strategies and the SPPs in the TPS. All amendments to the council Local Provisions Schedules in the TPS will need to be consistent with the TPPs.

The three existing regional land use strategies include strategies for managing natural hazards. The strategies guide where growth occurs in our settlements. They aim for growth to occur in appropriate locations and guide the application of zones in the TPS. These current regional strategies are subject to reviews which will include application of the TPPs at a regional scale.

Please see Regional Planning for more information.

Who does what?

Councils are central to administering the TPS, and handle the bulk of development applications in Tasmania, including assessing compliance with the zone and code requirements. Councils are also responsible for applying the zones and codes to the land in their municipality through their Local Provisions Schedule in the TPS. The Tasmanian Planning Commission approves each council’s Local Provision Schedule in accordance with the requirements in the Land Use Planning and Approvals Act 1993, including consistency with the future TPPs and the regional land use strategies.

The Minister for Planning sets the overall direction for the planning system through the approval and amendment of the:

• TPPs
• regional land use strategies, in partnership with local government and state agencies
• planning rules in the SPPs of the TPS.

These processes involve public consultation and independent review by the Tasmanian Planning Commission.

Resilience and Recovery Tasmania (RRT) in the Department of Premier and Cabinet provides an important advisory role in planning. It supports the application of emergency management principles to planning for natural hazards such as coastal inundation and erosion, landslip, riverine flooding and bushfire. RRT provides specialist advice to the State Planning Office and the Minister for Planning on natural hazard issues for the codes in the TPS.

Mineral Resources Tasmania (MRT) in the Department of State Growth provides data and mapping for geology, geomorphology and soils, including the preparation and maintenance of the landslip hazard mapping used in the Landslip Hazard Code of the TPS.

The Tasmanian State Emergency Service (SES) is responsible for planning and emergency risk management. SES leads the State’s emergency management planning and emergency risk management work. SES provides specialist advice to the State Planning Office and the Minister for Planning on natural hazard issues for the codes in the TPS and is also managing the Tasmanian Strategic Flood Mapping project.

More information

Understanding floods (bom.gov.au)

Risk Ready - TasALERT

Landslide Landslide Planning Map Update | Mineral Resources Tasmania (mrt.tas.gov.au)

Coastal Hazards Department of Premier and Cabinet (dpac.tas.gov.au)

Tasmanian Flood Mapping Project Reports - Tasmania State Emergency Service (ses.tas.gov.au)