Living Seawalls began as a research initiative at Sydney University’s Marine Science Institute, aiming to investigate the differences between artificial and natural coastal structures. Less than half of Sydney’s original natural shoreline remains due to the widespread construction of artificial barriers, which tend to be flat and uniform. In contrast, natural coastlines are more varied, with slopes and crevices that support diverse ecological habitats. Artificial structures often displace these habitats, making it harder for marine organisms to thrive.

The main idea behind Living Seawalls is to integrate natural elements into man-made marine structures, such as seawalls, by installing specially designed panels that mimic natural features. These panels provide safe spaces for marine organisms to settle, encouraging the development of marine ecosystems. Living Seawalls have been installed in several locations worldwide, and regular inspections help quantify their positive impact. At the site in Sydney Harbour, the Living Seawalls panels were placed at three different depths to accommodate a variety of species, both in the intertidal and subtidal zones. The intertidal zone, where the panels are only occasionally submerged, is a particularly stressful environment for marine life, so specific organisms adapted to these harsh conditions are targeted here. The lower zones, which are always submerged, encourage the growth of seaweed, a crucial base of the marine food web. Over three years, the panels have developed complex food webs, with seaweed, in particular, attracting many species of marine life. Seaweed plays a fundamental role as a primary food source and as habitat for various marine species. In some cases, the project team pre-seeded the panels with seaweed to jumpstart the ecosystem. Doing so, Living Seawalls have increased marine life by over 50% in many areas, a statistic supported by data collected through ongoing ecological monitoring. By providing protected space for organisms like oysters, which help filter and clean the water, the project enhances both biodiversity and water quality. In areas where sea life has successfully colonized the panels, the ecological functions of the seawalls are comparable to those of natural shorelines. The excursion to the Living Seawalls project directly ties into the research themes of “building with nature” and “coastal protection” by demonstrating how ecological principles can be integrated into man-made structures. By mimicking natural habitats and promoting biodiversity, Living Seawalls enhance coastal resilience while offering protection against erosion.