Sawmillers Reserve, McMahons Point

A unique collaboration of
science, government, philanthropy, industry and innovative design has enabled
the installation of the Living Seawall at Sawmillers Reserve in McMahons Point,
launched on the 28th February by Mayor Jilly Gibson, of North Sydney Council.

Living
Seawalls is an initiative of the Sydney Institute of Marine Science (SIMS) which builds on years of Sydney-based marine green engineering research. The Living
Seawalls team are assessing the ecological benefits of scaling up greening
interventions on seawalls, by adding different types of habitat enhancing tiles
to an entire seawall. Scientists from SIMS will be monitoring the tiles over
time to answer questions such as how different microhabitats on the tiles
influence colonisation of marine life and at what scale Living Seawalls can
enhance important ecosystem functions in Sydney Harbour, such as filtration
rates and primary productivity, which are directly linked to food and clean
water supply. 

The concrete tiles have been specially designed using 3D
technology to mimic natural habitat features of Sydney’s rocky shores and are
retrofitted to existing seawalls. The team is working with Reef Design Lab, a
Melbourne-based design studio, to develop these ecologically informed
structures.

Excitingly within weeks of
deployment, the Living Seawall at Sawmillers Reserve was colonised by a diverse
marine community. Several species of fish were also frequently observed
foraging around the seawall. In some cases, the complex microhabitats of the tiles
were completely overgrown and researchers observed limpets, chitons, snails,
oysters, barnacles, mussels and algae.

The current focus of Living Seawalls is to provide cost-effective
options for retrofitting existing structures on private and public seawalls to improve
their ecological value and enhance native biodiversity overall.

In
the future, the team anticipates developing additional habitat-enhancing
structures, such as seawall blocks, that can be produced and installed during
seawall construction or renovation. The team also plans to expand the project
to other artificial marine infrastructure such as pilings and breakwaters. By
simultaneously raising awareness of the growing problem of shoreline armouring
and providing cost-effective, customizable solutions for ecological improvement
of artificial structures, we anticipate opportunities for Living Seawalls will
continue to grow.