Welcome to the Cocos Keeling Island CHRMAP project page
The coast is important to everyone. It provides places to live, do business, exercise and enjoy. However, the coast is constantly changing through storm events, rising sea levels and the changes that people make to the coastline. The Cocos (Keeling) Islands are no different and are particularly affected by low-lying coastlines.
The Australian Government has partnered with the Western Australian (WA) State Department of Planning, Lands and Heritage (DPLH) and the Shire of Cocos (Keeling) Islands (the Shire) to develop a Coastal Hazard Risk Management and Adaptation Plan (CHRMAP) to understand how the Island coastlines will be affected by ‘erosion’ and ‘inundation’ in the future and prioritise and implement management responses.
Latest News
July 2025 Project Update: public feedback has now closed
Formal Submissions have now closed. We thank the whole community for getting involved and providing feedback. We will be able to provide some updates on the outcomes soon.
The Draft CHRMAP remains available for viewing in the Document Library whilst feedback is being reviewed.
A CHRMAP is a technical document with complex terminology and language, so the project team has also created a summary document, distilling the most important information about risk and management options. You can access this in either English or Cocos Malay. You can find these in the Document Library.
The CHRMAP is not yet final. Although developed over a long period of time and with input from many members of the Cocos community, the documents are still in draft pending review of the feedback of the community and stakeholders, and final endorsement by Government.
Coastal Mapping Descriptions
Between 2018 and 2021 the Australian Government in collaboration with the WA Department of Planning, Lands and Heritage commissioned a Coastal Vulnerability Assessment for Home Island and West Island (CVA report). The CVA report identifies coastal hazard risks and assesses the vulnerability of built and natural assets to erosion and inundation hazards, in accordance with the requirements of the WA government’s coastal policies.
Based on these assessments, coastal hazard maps were produced for Home Island and West Island over the next 100 years. The maps show areas predicted to be affected by coastal hazards such as erosion and inundation. It is important to bear in mind that these predictions are based on the possible impacts from a combination of estimated sea level rise and extreme weather events, as well as historical observations of relevant environmental factors. How the erosion hazard and inundation mapping was developed is explained in more detail below. These areas were calculated using the methodology prescribed in WA State Planning Policy 2.6 – Coastal Planning (SPP 2.6) and have been identified for a 100-year planning timeframe, broken up into 2018, 2031, 2068 and 2118 timeframes. The maps have been prepared by qualified coastal specialists and reviewed by the Australian Government.
The methodology for calculating coastal hazard areas does not take into account future action that may be taken to adapt to coastal hazards.
Familiarise yourself with the predicted coastal hazard lines and the inundation mapping to see how erosion and inundation have been predicted to affect the coastline and the coastal settlements on Home Island and West Island.
How will the CHRMAP affect my property?
The CHRMAP identifies the areas that are at risk of being affected by coastal hazards and when they are likely to occur and makes recommendations on appropriate management options for different areas.
The affect on your individual property depends on where it is located as the hazards and risks vary throughout the coastline and adjacent coastal areas.
The Draft CHRMAP will help you understand if and how your property may be affected.
The hazard lines represent the combined allowance calculated from the following factors as outlined in SPP 2.6:
- Predicted erosion under a severe storm - storm erosion from a potential one in 100-year storm event (S1);
- The historical rate of shoreline change - calculated as 100 times the historic annual rate of erosion (S2);
- Predicted sea level rise - calculated as 100 times the adopted sea level rise value of 0.9 metres over a 100-year timeframe (S3).
Home Island and West Island have sandy coastlines. The line on the hazard map is a combination of S1, S2 and S3, plus the 0.2 metre/year uncertainty allowance provided for in SPP 2.6 for sandy coastlines.
The erosion hazard lines provide an indication of the possible extent of erosion at each of the dates indicated by the lines if a combination of these factors occur.
The dates should not be read as precise; rather, the erosion is likely to occur at a time close to the year but could occur much sooner or much later. For this reason, it is recommended that monitoring and review is regularly undertaken.
A modelled approach using simulation periods was used to map inundation areas. The inundation areas represent the peak steady water levels i.e. still water levels plus an allowance for wave-driven water levels, including overtopping of coastal structures, in accordance with SPP 2.6.
The inundation areas are shown as Australian Height Datum (AHD).
