The Gold Coast Seaway

The Gold Coast Seaway, completed in 1986, stands as an impressive feat of engineering that helps control the shape of the coast. The construction of this artificial waterway was vital to stabilise the shifting Nerang River mouth and The Spit, which was drifting northwards by 60 metres each year.

The solution involved constructing two large rock walls to create a fixed river entrance. These walls were designed and positioned to reduce the entry of ocean swells, providing safer passage for vessels. In conjunction, Wave Break Island was built from dredged material, creating an effective barrier, protecting the Broadwater, Biggera Waters and Labrador against waves and storms.

One remarkable feature of the Gold Coast Seaway is the Sand Bypass System, the first of its kind in the world. This pioneering facility can move up to 500 cubic metres of sand per hour, pumping sand from The Spit via a pipeline across the Seaway to South Stradbroke Island. This process imitates the natural movement of sand and helps to maintain the Seaway’s stability and water quality by preventing the further northward drift of The Spit.