Proposed Temporary Local Planning Instrument (TLPI) 01/24 Flood Hazard Area

The Fraser Coast Region has a long history of being impacted by flooding and storm tide inundation. The State Planning Policy (SPP) requires Council to identify and manage natural hazards risks in areas that are susceptible to flooding and storm tide inundation. 

Council has decided to make a Temporary Local Planning Instrument (TLPI) to address SPP requirements as an interim policy response whilst work is undertaken to update the Planning Scheme. 

Council has recently completed six flood studies, providing new or up to date mapping of flood extents within these catchments. This information will be used that development within the flood hazard areas in these catchments is appropriately regulated and managed. 

Implementing these changes sooner through the TLPI, rather than waiting for the Planning Scheme to be updated, will help the communities in these areas to improve their understanding of risks of flooding and how they can improve their resilience. 

Flood studies provide Council, the community and developers with the most up-to-date understanding of where and to what extent flooding might occur due to different storm events that happen locally or in upper catchment areas. Each study uses the most currently available information on topography, existing and proposed development, and rainfall and creek/river flows in that catchment, together with the latest computer software to achieve this outcome. 

Flood studies are a mandatory requirement to manage flood hazard risks and their impact on people, property, and infrastructure, and are a requirement of the Planning Act 2016 and State Planning Policy (SPP).

These studies provide valuable insights that help in managing development and planning future land use in areas prone to flooding or inundation. These studies also help Council in emergency planning to ensure the safety of residents during natural disasters like cyclones and large flood events.

It's important to note that flood studies do not increase the risk of flooding. Instead, they help identify areas that are vulnerable to such natural hazards. Flooding can cause significant damage to properties and infrastructure and can pose a threat to life. Without flood studies, residents, businesses, and entire communities may not be aware of the risks they face.

The consequences of not being aware of these risks could include:

• lack of resilience to natural hazards,
• building new developments in high-risk areas,
• inadequate insurance coverage,
• reduced ability to recover from disasters,
• damages or loss of property or business, including potential loss of life.

Yes, the recent flood studies undertaken for catchments in the TLPI have incorporated the potential impacts of Climate Change including both sea level rise and increasing rainfall intensities.

Consistent with industry best practice, national design standards and recommendations from the Queensland Flood Commission of Inquiry, Council will incorporate Climate Change considerations all new flood studies within the Fraser Coast region.

Inclusion of such considerations is critical to the forward planning of areas within our region due to our coastal location, significant extent of foreshore frontage and low-lying adjacent land, together with the major river systems and other high flood risk areas located within the Fraser Coast region.

The requirements in the Planning Act 2016 and Minister's Guidelines and Rules for making a Temporary Local Planning Instrument (TLPI) do not include provisions for statutory public consultation.

The requirements in the Planning Act 2016 and Minister's Guidelines and Rules for making a Temporary Local Planning Instrument (TLPI) do not include provisions for statutory public consultation.

Flooding is when a normally dry area is covered in water.

No two floods are the same, with some of the factors that influence the size of a flood including where the rain falls, the intensity and duration of the storm event, how wet the ground is, how big an area the storm covers, and the topography of the land between you and the storm event.

Click the link below to watch a video that demonstrates what a flood can look like: https://youtu.be/QC3peH_3LWA

There are three main types of flooding:

• Riverine flooding,
• Overland flooding,
• Storm surge and storm tide.

Riverine flooding occurs when the creek or river can no longer contain all of the water flowing into the watercourse, resulting in flooding of nearby areas when the water flows over the banks of the creek or river.

Overland flooding occurs when the rain falls on land away from the creek or river and has to flow over land to get to the watercourse. If the intensity of the rainfall is greater than the water can flow away from that area, the water level will build up and cause flooding. 

In urban areas, where there are lots of hard surfaces such as roads and house roofs, overland flows can concentrate very quickly and cause flash flooding when the water cannot flow away quickly enough.

In rural areas, where theer may be limited information on river or creek flows, heavy rains in the upper catchment may cause flooding downstream with little or no warning, which is also known as flash flooding. 

Storm surge and storm tide happen when there is a large storm over a body of water, whether a lake or the sea, and wind pushes the water onto the beach or surrounding land to a higher level than would normally occur due to a high tide.

Depending on the duration, intensity and location of the storm, areas can experience different types of flooding from the same storm, which might be separated in time or might occur simultaneously.

You can view the TLPI – Flood Hazard Area by clicking on the link below:

Proposed TLPI 1-24 Flood Hazard Area

Alternatively, you can request a flood search containing property specific flood information for stormwater, riverine and/or storm-tide flood risk types.

Council’s mapping represents the flood risk, or depth and extent of flooding that could occur at your property, but it is not able to predict when that flood event might occur.

Floods do not occur in a regular pattern and there may be long periods where there are no floods, followed by short periods with several floods. The information on how often a partilcular sized event can happen changes as we get more history on rainfall events within the catchment, and more gauges to better understand how much rainfall occurs in different parts of the catchment. 

The frequency, intensity, and extends of flooding can also vary over time due to natural changes in the catchment, such as those caused by bushfire or cyclones, and man-made changes, such as urbanisation and climate change. 

The information that Council makes available to the public is based on the most recent flood studies of the catchment, with Council focussed on updating flood studies on a regular basis and providing that information to the community as quickly as possible. 

Although you have never been flooded before, there is no guarantee it won’t happen in the future. The flood studies show a range of scenarios and therefore provide an estimate of areas that may be affected during different types of flood events. Across a number of years, Council has been undertaking studies to better understand rainfall patterns and topography so we can better predict where water may flow.

Your likelihood of experiencing a flood, whether once or more often, depends on many different factors, including where you are in the catchment (near the top or the bottom of the catchment), the size and duration of the storm event, how much rain has recently fallen in the catchment, and how much freeboard your house has (how high above the ground your house is).

Flood studies consider many different storm durations and intensities to estimate the frequency of different sized flood events. 

The calculations to determine the frequency with which different sized events might occur depends on the amount of rainfall data available for that particular catchment, which depends on the number and location of rain gauges within the catchment, together with how long those gauges have been collecting data and what changes in development or farming practices have occurred in the catchment over that time.

The frequency of different events used to be expressed in terms of a flood being a 1 in ‘x’ year event, such as a 1 in 100 year event, or the event having a 1 in 100 year Average Recurrence Interval (ARI).

Nowadays, the frequency of different events is typically expressed as a percentage of how likely it is to occur in any given year. This means that an event that used to be described as having a 1 in 100 year ARI, is now described as an event with a 1% Annual Exceedance Probability (AEP) 

To allow for consistency in what engineers, architects, and builders need to know to design the floor level of a house, or other types of buildings, regulators require Council to provide information on what the 1% AEP level is for a particular property.

Note that a 1% AEP, or a 1 in 100 Year ARI, flood event does not mean that that flood event can only occur once in 100 years or can only occur 100 years after the last time an event of that size occurred.

The information on how often a particular sized event can happen changes as we get more history on rainfall events within the catchment and more gauges to better understand how much rainfall occurs in different parts of the catchment. 

Flood levels, and the associated mapping, vary according to many different factors, such as what type of flooding it is - overland, riverine, or storm tide, how large the flood event is, the topography of the land near you and your neighbour's properties, where houses and sheds are located on a property and how much of the property is covered by hard surfaces such as roofs, driveways. 

Flood studies, and their associated mapping, use the most recent topographic information available at the time of the study to create a digital model of the catchment. Unfortunately, it's not feasible to adjust the digital model to allow for works, such as extra filling being placed on a property or a new shed being built, that are undertaken after the model been created.  

Questions regarding changes to your insurance schedule should be directed to your insurance provider. Insurers do their own flood risk assessments and risk mapping, independent of local government.

Insurance companies spend time and resources researching areas of Australia to map flood prone areas and assign risk estimates to each area.  Insurance companies use data from a range of sources, including flood mapping (where available), terrain data and independent hydrologist reports. Industry bodies such as the Insurance Council of Australia often complete this on behalf of insurance companies, and then each company considers how to adjust premiums to reflect how likely it is that an individual property might flood.

The Insurance Council of Australia recommends that consumers shop around if they are dissatisfied with their current cover.  For more information about flood insurance visit the Floodplain Management Australia webpage at: https://www.floods.asn.au/site/flood-insurance-fact-sheets. Additionally, the Insurance Council of Australia has useful information about how to reduce your risk, disaster resilient retrofitting, mitigation measures and their impact on premiums at: https://insurancecouncil.com.au/consumers/reduce-your-risk/.