Karragarra Island rock armour seawall

Project overview

Following a severe weather event in early 2022, Council installed a sandbag seawall and conducted sand nourishment works as an interim solution to protect the foreshore. While effective in the short term, sandbags are not sustainable for long-term resilience against severe weather and coastal erosion. The rock armour seawall will replace the sandbag seawall, which has reached the end of its life.

The rock armour seawall will protect critical infrastructure such as Esplanade Road and the Energex HV submarine electricity cable. These assets are crucial for maintaining connectivity and electricity supply to homes and businesses on the island and neighbouring islands.

Project commencement

Construction is expected to commence August-September 2025 (subject to weather conditions and project constraints).

Long-term benefits

• Proven to withstand severe weather conditions.
• Ensures the long-term stability of the electricity supply.
• Ensures accessibility remains on The Esplanade Road.
• Safeguards the foreshore from erosion and enhances coastal ecosystem stability.
• Mitigates the impacts of rising sea levels, storm surges, and extreme weather events.

Community safety and connectivity

Installing a rock armour seawall is essential for community safety, maintaining access to essential services, and protecting the environment. It is the most effective solution to preserve our coastline and secure Karragarra Island's future.

Image above: Karragarra Island rock seawall design at esplanade.

Frequently asked questions

Why can't Council keep the sandbags and just maintain them?

While sandbags provided an effective interim solution, they are not sustainable for long-term protection. Over time, sandbags degrade and lose their structural integrity, making them less effective against continuous and severe weather conditions and coastal erosion. Maintenance of sandbags is also labour-intensive and costly, requiring frequent replacements. Council has recently complete maintenance repair of several damaged sandbags that were installed during 2023.

A rock armour seawall offers a more durable, long-lasting solution that requires less ongoing maintenance and provides superior resilience against severe weather and erosion.

Why can’t you use sandstone blocks for the seawall?

Sandstone, although aesthetically pleasing, does not offer the same level of durability and resistance to coastal erosion as rock armour. Sandstone is more susceptible to weathering and can break down over time, especially in harsh marine environments. Rock armour, made of large, durable rocks, is specifically designed to withstand the severe conditions of coastal areas, ensuring long-term protection and stability.

How will the construction of the seawall affect beach access and community activities?

The construction of the rock armour seawall, which will be approximately 60 metres long, 5.5 metres wide, and incline to 1.5 metres high will minimally impede beach access once completed. Temporary access restrictions may be necessary during construction to ensure public safety.