Information and resources about protecting and managing the Western Australian coastline.
Coastal hazard risk management and adaptation plans in WA
The table provides an evolving list of coastal hazard risk management and adaptation plans (CHRMAP) that have been completed by local governments in Western Australia.
Towards a National Collaborative Approach to Managing Coastal Hazards in Australia
In early 2020, an Intergovernmental Coastal Hazards Working Group was established comprising of the Australian Local Government Association and State, Territory and Commonwealth Government representatives. The Group’s objectives were to:
- Collate existing information on the national scale and extent of coastal erosion and inundation risk, their impacts, current management effort and estimates of future management needs
- Explore opportunities for a collaborative approach across jurisdictions to manage coastal erosion and inundation
- Recommend actions to the Energy and Climate Change Ministerial Council.
A report was prepared by the Coastal Hazard Working Group which was considered and noted by the Energy and Climate Change Ministerial Council in July 2023.
Assessment of Coastal Erosion Hotspots in Western Australia
In a national first, a state-wide assessment of the extent and scale of coastal erosion has been undertaken in Western Australia.
The Assessment of Coastal Erosion Hotspots in WA (2019) identifies 55 locations — 15 metropolitan and 40 regional — where coastal erosion is expected to have a significant impact on public and private property or infrastructure in the next 25 years.
The assessment was commissioned by the State Government and undertaken by Seashore Engineering Pty Ltd.
An Information Sheet provides an outline of the findings and recommended actions. Detailed profiles for each hotspot are available in the assessment at Appendix D, from page 77.
For more information or if you have any questions please email coastal@dplh.wa.gov.au or coastalmanagement@transport.wa.gov.au
Coastal inundation
Statewide Coastal Inundation Assessment for Western Australia
A state-wide assessment of the potential extent and scale of coastal inundation over the short to medium term has been undertaken in Western Australia.
The Statewide Coastal Inundation Assessment for WA (2024) identifies the potential inundation threat during the next 25 years, determining the risk to coastal communities and examining pathways to manage the threat. The assessment was undertaken across 45 coastal local government areas and identified 23 at risk locations.
The assessment was commissioned by the State Government and undertaken by Seashore Engineering Pty Ltd.
For more information or if you have any questions please email coastal@dplh.wa.gov.au or coastalmanagement@transport.wa.gov.au
Coastal Inundation Modelling
The WAPC, together with the Department of Planning, Lands and Heritage, engaged the services of Geoscience Australia to undertake an assessment of Bunbury’s and Busselton’s coastal vulnerability.
The aim of these studies were to improve the understanding of the potential consequences of a storm surge event, both under present conditions and in future scenarios where climate change has caused sea levels to rise.
Information sheets and full reports and are available for both studies.:
WA State coastal landform map
The map outlines the coastal landform types in WA: sandy, rocky, mixed sandy and rock, coastal lowlands, tidal reaches of inland waters and islands. The indicative risk of landform change for these coastal types is also mapped.
Under SPP 2.6, foreshore reserves should take into account coastal processes based on the physical and biological features of the particular coastal environment, such as coastal landform types. In determining the coastal foreshore reserve it is important to recognise time and space scales in which the landforms and their driving processes operate for the planning timeframe. The planning timeframe should also take into consideration the impacts of climate change on coastal landforms.
Hard copy maps are available for pick up from the Perth Department Office. For more information please contact the department.
LiDAR Survey and Bathymetric Mapping
Western Australia now has a complete high-resolution bathymetric and terrestrial coastal survey for more than 700 kilometres of coastline – from Cape Naturaliste in the south to Horrocks in the north.
The baseline information will be used to inform decision-making on the coast and ensure better management of coastal resources.
Data for the survey was collected using LiDAR (Light Detection And Ranging) technology, which involved aircraft-borne remote sensing technology rapidly transmitting pulses of light that reflect off the underwater terrain and other marine features along the coastline.
The State Government commissioned new high-resolution bathymetric data for 400 kilometres of coastline between Hillarys and Horrocks; and around the Abrolhos Islands and five inland waterways in the southwest (Peel Inlet, Harvey Estuary, Leschenault Estuary, Hardy Inlet and Wilson Inlet). Fugro LADS Corporation undertook the imaging survey between March and May 2016.
The resulting maps show incredible three-dimensional features of the State’s underwater coastal terrain.
The LiDAR imagery has revealed new features of our underwater coastal terrain such as a ledge offshore from Quinns and a reef system offshore from Cervantes which until now have gone undetected and not shown on navigational charts. This new information will be invaluable for recreational and commercial boating and fishing safety. A natural harbour system has been discovered offshore from Dongara and ancient offshore sand dune systems have been located, such as an ancient rivermouth system near Capel, south of Bunbury.
The data is available online in GeoPDF format, which can be viewed in Adobe Reader, on the Department of Transport website.
Data from a similar survey undertaken in 2009 for 300 kilometres of coastline between Two Rocks and Cape Naturaliste has been widely used, including by Geoscience Australia as a baseline for storm surge and inundation modelling for Bunbury and Busselton. It also added high-resolution detail to the Federal Government’s National Coastal Risk Assessment to identify coastal environments, communities and infrastructure at risk from impacts of climate change. The 2009 survey data is available in TIF format through the Composite Surfaces- Multibeam LIDAR Laser (DOT-022) dataset on data.wa.gov.au.
The complete LiDAR data will continue to be used for a range of purposes across Western Australia, including:
- defining the general shape of the seabed and determining the broad classification of seabed materials and benthic habitat
- analysing the impacts of sea level rise, storm surge and inundation on coastal assets, infrastructure, public safety and the environment
- informing the appropriate location of future development and placement of coastal infrastructure
- providing baseline information to model coastal processes and assist in coastal hazard risk management and adaptation planning as required by State Planning Policy 2.6 State Coastal Planning Policy
- modelling flooding, groundwater, surface water, tsunamis and storm events
- informing the development of regional and local coastal plans
- identifying areas potentially at risk from storm surge, inundation, erosion and high winds
- identifying areas where physical protection measures are required to protect assets and people
- identifying areas yet to be developed where land use planning changes will be required
- providing a basis for contingency planning and managing natural disasters
- preparing marine plans
- creating digital elevation models.
The bathymetric LiDAR also complements land-based LiDAR surveys commissioned by the Department of Water and Environmental Regulation (DWER), which have supported digital terrain modelling to determine patterns of flooding, groundwater/surface water interaction and ecological systems. For more information on these land-based surveys visit the DWER website or email spatial.data@water.wa.gov.au.
