The realignment of Oyster Creek, undertaken as part of the M1 Pacific Motorway upgrade between Burleigh and Palm Beach on the southern Gold Coast, provided an opportunity to integrate ecological design principles into major infrastructure and evaluate their effectiveness. Oyster Creek, a tributary of Tallebudgera Creek, was realigned into a newly constructed 870 m long channel extending from the tidal interface upstream of the M1 culverts. To meet environmental approval conditions and maintain ecological connectivity, the new reach design included large refuge ponds fitted with LUNKERS and large woody debris, connected by run habitats stabilised with cross‑vanes to manage flow and reduce velocities for fish passage.
Post‑construction monitoring was undertaken across three survey rounds using boat electrofishing and netting to assess the new fish community, habitat use and passage. Seven native fish species were recorded in the freshwater reaches, including juvenile empire gudgeons (Hypseleotris compressa) as small as 10 mm migrating in the run habitats and adult sea mullet (Mugil cephalus) up to 445 mm and large longfin eels residing in the pools. A turtle hatchling and a diversity of waterbirds have also been found at the site. By comparison, pre‑construction surveys detected only three native species of fish. These results demonstrate that the reconstructed channel is functioning effectively, facilitating upstream movement and supporting a developing native fish assemblage.
The Oyster Creek realignment demonstrates that ecological design can be successfully embedded in infrastructure, with the new channel rapidly colonised and delivering measurable ecological benefits alongside engineering and regulatory performance.