Cocos Islands Under Threat GeoRock™ GSC’s to the Rescue

Just 2750 kilometres North West of Perth within the pristine blue waters of the Indian Ocean lies Australia’s last true untouched paradise, the Cocos (Keeling) Islands. Home to some 600 people, comprised mostly of the local Cocos-Malay residents, this remote island destination attracts thousands of visitors each year, with its kite and windsurfing, exceptional fishing and diving.

The Problem

This tranquil paradise is under relentless attack from the forces of the open seas, with severe foreshore erosion resulting in the destruction of important  infrastructure, such as main roads, air strip and housing. With the highest points on the Islands being 2-3m above sea level, the islanders have their heads just above water.

Federal Government funding was granted to Cocos Island to address the issue of foreshore erosion. Conventional method of armouring with large stone is impractical & cost prohibitive. Unfortunately there is no rock on Cocos Island, only sand and coral, which meant a different approach was needed to defend the foreshore.

The Solution

The Shire of Cocos (Keeling) Islands chose to use GeoRock™ GSCs (geotextile sand containers)to remediate a severely eroded section of William Keeling Cres. GeoRock™ provides an aesthetically pleasing, soft armour solution comprising a staple fibre geotextile with exceptional UV resistance, superior tensile strength and high levels of abrasion resistant.

The following were installed on this project;

• GeoRock™ 1.0m³ Anti Vandal (AVL) Geotextile Sand Containers: +5,350 units

• ProFab® ULTRA AS1200X Nonwoven Revetment Filter Geotextile: +5,500m²

The GeoRock™ 1.0m³ units were the preferred option by the Shire as it meant they were benefiting from 25% greater mass than traditional 0.75m³ units. The higher mass results in greater unit stability with a negligible increase in unit cost and improved installation efficiencies. This is critical on islands with a narrow tidal window for works access.

The Shire of Cocos (Keeling) Islands achieved all structural design objectives within their financial and timing allowances.  Feedback from the local island community also suggests they are happy with the ‘soft armour’ approach taken by the Shire whilst comforted by reduced storm threat levels.

For further information please contact sean@globalsynthetics.com.au