Chapter 3 Water and biodiversity in South Australia
As the driest state in the driest inhabited continent in the world,
South Australia received considerable attention at the height of the drought
experienced by southeastern Australia from 1997 to 2009, the worst drought in
the 110-year instrumental record. The impact on the
Coorong, Lower Lakes and Murray Mouth (CLLMM) region, in particular, was a
major focal point. Located at the downstream end of the Murray–Darling River
system, there was concern that the drought, combined with the over-allocation
of water resources upstream, had severely compromised the region’s
internationally significant biodiversity.
Some of the environmental impacts of the drought have abated since 2009.
However, many of the challenges for the region remain, and these were part of
the focus of the Committee’s site inspections in the CLLMM region on 16 May
Apart from this focus, the Committee was interested to see the
development of innovative practices for the sustainable use of water resources
and the protection of biodiversity assets. On 17 May 2012, the Committee
inspected the constructed Greenfields Wetlands, which contribute to addressing concerns
about the availability of water from the River Murray and the potential
ecological impacts of stormwater run-off on marine ecosystems.
Over these two days, the Committee’s site inspection program in South
Australia addressed matters relating to freshwater, marine and terrestrial biodiversity;
impacts of biodiversity loss on human populations; the sustainable use of
natural resources; and community engagement.
The Coorong, Lower Lakes and Murray Mouth region
The CLLMM region is approximately 142 500 hectares in size and contains
a diverse range of freshwater, estuarine and marine habitats.
The region is a Ramsar site, known as the Coorong and Lakes Alexandrina and
Albert (Lower Lakes) Wetland of International Importance. It is an area of high
biodiversity value, and home to many endemic plant and animal species. The
Coorong and Lower Lakes have been recognised by BirdLife International as
Important Bird Areas, given their significance for resident waterbird,
migratory shorebird, and orange-bellied parrot populations.
The Coorong also acts as an important refuge for animals during times of
The Ramsar site covering the region is currently used for several
purposes, including conservation, recreation, water storage and extraction,
grazing and cropping, and urban and residential development. Local employment
is mainly in the agriculture, viticulture, fishing, manufacturing, and tourism
Years of drought and over-use of water had left these ‘internationally
significant wetlands dry, the lakes disconnected, communities and industries
under significant stress,’ and native species threatened.
Figure 3.1 Location of the Coorong, Lower Lakes, Murray
Mouth, and Barrages
from: S Lamontagne, K McEwan, I Webster, P Ford, F Leaney and G Walker, Coorong, Lower
Lakes and Murray Mouth: knowledge gaps and knowledge needs for delivering better
ecological outcomes, Water for a Healthy Country National Research Flagship,
CSIRO, Canberra, 2004, fig. 1, p. 3
The Committee visited six distinct sites in the CLLMM region—which are
briefly described below—and gained an insight into some of the complexities
associated with natural resource management in the region. Throughout the site inspection
program, the Committee was accompanied by Mr Russell Seaman, Environmental
Advisor with the South Australian Department of Environment, Water and Natural
Resources (DEWNR). At each site, Mr Seaman
provided briefings which focused on: the region’s biodiversity values; ongoing
and climate change-related threats to biodiversity; DEWNR initiatives; and the
importance of community engagement in natural resource management.
During the inspections, the Committee received the following documents
from the DEWNR:
- BushBids Murray
Plains and Rangelands: Woodland, South Australian Murray–Darling Basin
Natural Resources Management Board.
- Applying a climate
change adaptation decision framework for the Adelaide–Mt Lofty Ranges
Natural Resource Management Board, South Australian Department of Water,
Land and Biodiversity Conservation.
Lakes Alexandrina and Albert
The River Murray, Australia’s longest river, terminates in South
Australia at the Southern Ocean, having passed through Lake Alexandrina, the
Murray estuary and, finally, the Murray Mouth. Lake Albert is a terminal lake
connected to Lake Alexandrina by a narrow channel. Lakes Alexandrina and Albert,
collectively referred to as the Lower Lakes, are comprised of fresh to brackish
and saline waters, and support significant biodiversity, including threatened
bird species such as the orange-bellied parrot, Australasian bittern, and fairy
During the site inspections of the Lower Lakes, the Committee was briefed
on local biodiversity values, threats to biodiversity including land use and
climate change, and some of the DEWNR’s relevant climate adaptation measures.
Clayton Bay and Dunn’s Lagoon
Clayton Bay is located on the Lower Murray River. Dunn’s Lagoon (also
known as Clayton Wetland) is a back basin of Lake Alexandrina and located on
the east side of the township of Clayton. It is a large, open, permanent
wetland, and is relatively shallow in most parts. The wetland has three main
connections with Lake Alexandrina. These broad, shallow inlets incorporate
three islands including Goose Island to the west and Goat Island to the east.
Water levels in the wetland fluctuate in accordance with water levels in Lake
Dunn’s Lagoon spans several land tenures including private and council
land. The wetland is managed by a stakeholder group and is a popular place for
recreational pursuits such as boating. The private land surrounding the wetland
is used primarily for grazing.
During the inspection of Dunn’s Lagoon, the Committee heard that the
area is one of the top five ecologically important sites in the CLLMM region. Indeed,
areas such as Dunn’s Lagoon are considered the drivers of the ecology of Lakes
Alexandrina and Albert.
Milang Lakes Hub
The Lakes Hubs at Milang and Meningie were established in 2009 and 2010
respectively, to help disseminate information and provide collaborative links
between government and local communities. The Hubs provide a conduit between
government and community members to deliver environmental restoration projects
in the region.
The Lakes Hub at Milang is an initiative of the Milang and District
Community Association and is part of the South Australian Government’s Murray
Futures program, funded by the Australian Government’s Water for the Future
initiative. The Committee visited the Milang Lakes Hub and received briefings
- Ms Karyn Bradford,
Lakes Hub Executive;
- Ms Carole Richardson,
Local Action Planning Coordinator; and
- Ms Gemma Cunningham,
Community Engagement Manager, DEWNR.
At the Milang Lakes Hub, the Committee received the following documents:
- Seeds to reeds:
Lower Lakes Community Nurseries Newsletter, 10th edition, Lakes Hub, March
- Weekly Bulletin,
No. 96, Lakes Hub, 7 May 2012.
- Local people,
local issues, local action, Goolwa to Wellington Local Action Planning
- Development and
implementation of a community engagement strategy for the Lower Lakes
bioremediation and revegetation project, 2009–2011: Final report, Milang
& District Community Association Inc.
Wyndgate, Hindmarsh Island
Hindmarsh Island is located on the Lower Murray River, near the town of
Goolwa. It is a popular tourist destination, and much of the land on the island
is used for agricultural purposes.
The Committee visited the DEWNR office at Wyndgate on Hindmarsh Island,
which is one of the sites from which Coorong National Park is currently
managed, and received briefings from:
- Mr Tim Hartman,
Ngarrindjeri Regional Authority; and
- Mr Lachlan Sutherland,
Ngarrindjeri Partnerships Coordinator, DEWNR.
At Wyndgate, the Committee received briefings on the natural and
cultural values of the area, impacts of recent droughts and related management responses,
and programs to engage Indigenous communities in biodiversity conservation and
the co-management of national parks.
Hindmarsh Island has freshwater on its northern shore and saltwater on
the southern shores. The waters are separated by a series of barrages,
constructed between 1935 and 1940, which are intended to maintain a consistent
water level in the lakes and to protect agricultural areas from exposure to
The five barrages—often collectively referred to as the Goolwa
Barrages—span the Goolwa, Mundoo, Boundary Creek, Ewe Island and Tauwitchere
channels. The Committee travelled over some of the barrages and received
briefings on the design of the structures, the importance of fishways and water
flow to the ocean, and the state of the Coorong and Murray Mouth.
The Coorong and Murray Mouth
The Coorong is a long, shallow, brackish to hypersaline lagoon more than
100 kilometres long. It is separated from the Southern Ocean by a narrow sand
dune peninsula. The Coorong has been one of Australia’s most important sites
for shorebirds, but decreased environmental flows in recent decades have led to
declines in many species. Nevertheless, BirdLife
International identifies more than a dozen globally-important bird species
supported by the Coorong, including threatened species such as the
orange-bellied parrot, fairy tern, Australasian bittern, and hooded plover.
During its inspections of the Coorong and Murray Mouth,
the Committee received briefings on the biodiversity values of the area, water
management policies, and the effects of drought.
Figure 3.2 Committee members at one of the Goolwa Barrages
courtesy of committee secretariat
Greenfields Wetlands, Adelaide
The City of Salisbury is located on the northern fringes of Adelaide
and, with approximately 130 000 residents, is the second largest local
government community in South Australia. The City has experienced rapid
residential and commercial growth and is South Australia’s most productive
The City of Salisbury has established a stormwater recycling program
that provides business and community customers with non-potable water. This has
contributed to reducing Adelaide’s overall reliance on the River Murray to meet
its water requirements, and has delivered biodiversity benefits for the area
and for adjacent marine ecosystems.
Greenfields Wetlands, which the Committee inspected on 17 May 2012, is
one of over 50 constructed wetlands that help the City manage its water supply
and improve water quality. During its inspection, the Committee was briefed by Mr
Colin Pitman, General Manager, City Projects, City of Salisbury. The Committee
received the following documents:
- City of Salisbury, Water
- The Benefits of Our Wetlands.
- Frogs and Froglets.
- Little Wetland Critters.
- Managing Mosquitoes.
- Stormwater Treatment.
- Harvesting Our Stormwater.
- Monitoring Water Quality.
During the inspection, the Committee heard about: the contribution of constructed
wetlands to the sustainable use of natural resources; connectivity between
ecosystems; and building resilience in ecosystems.
Issues explored in South Australia
As noted earlier, the Committee’s inspections in South Australia included
a focus on freshwater biodiversity and sustainable natural resource use, and the
impacts of these on human communities. The Committee received extensive
briefings on: the threats to the biodiversity of the CLLMM region and how
resilience is being built into the region’s ecosystems and associated human
communities; natural resource management in a complex governance framework; and
the benefits of constructed wetlands in an urban environment.
Threats to biodiversity in the CLLMM region
During its site inspection program, the Committee was informed that
there had been record low river flows to the CLLMM region, particularly due to water
management practices throughout the Murray–Darling Basin. The Committee heard
that the levels of water extraction for human use throughout the basin had left
insufficient water for the environment.
More recently, extended drought and the early impacts of climate change
had added to the site’s ecological stress. The drought had exacerbated the
results of years of land clearing and intensive agricultural use in the region.
In addition, climate changes—particularly higher temperatures, less
autumn and winter rainfall, and higher levels of atmospheric carbon dioxide
potentially affecting the water consumption of plants—are expected to result in
reduced run-off in the Murray–Darling Basin, leading to lower environmental
flows in the CLLMM region.
Together, the existing threatening processes in the region have resulted
in a range of biodiversity impacts, including habitat loss through the drying
out of wetlands, competition from pest species, and exposure of acid sulfate
soils. These were the focus of briefings the Committee received during site
inspections in the region.
The Committee heard that falling lake levels and lack of flow over the
barrages into the Coorong lagoon have resulted in reductions in vegetation, the
disconnection and drying out of wetlands, reductions in threatened fish species
numbers, and significant decreases in shorebird numbers.
The Committee inspected Dunn’s Lagoon, which featured in news reports in
2009, when the wetland dried out completely. Water flow was restored in April
2010. In the interim, however, marine worms had moved into the area and colonised
any available hard substrate. They encrusted the shells of eastern long-necked
turtles, resulting in the death and injury of many turtles. The worms also
moved into plumbing and water supply systems, blocking and damaging pipes and resulting
in significant public infrastructure costs.
The Committee examined and received briefings on sulfuric soils in the
region. Although such soils are a naturally occurring phenomenon, their exposure
to oxygen can produce sulfuric acid, which can have detrimental effects on
wetlands. When many parts of the CLLMM system dried out during the recent
drought, acid sulfate soils were exposed to the air and there were concerns
about the potentially devastating effect this could have on the region’s biodiversity.
Indeed, the Committee heard that, had the drought continued for another one or
two summers, the entire region’s ecosystems would have been on the verge of
The Committee notes the high biodiversity values of the CLLMM region. It
appreciates there are challenges posed by periods of drought and the pressures
from human water use requirements, and recognises the likelihood of climate
change exacerbating existing threats to the region’s biodiversity. As climate
change introduces more uncertainty, effective water management and biodiversity
conservation policies will be essential for responding quickly to the region’s
Although river flows have increased in recent years, resulting in higher
water levels reaching the CLLMM region, the Committee heard that many of the
issues affecting the region remain. If these are not remedied or managed
effectively, there could be serious and irreversible environmental impacts. It is
likely that appropriate intervention and management will be even more pressing
considerations in light of projected climate changes.
Enhancing the resilience of ecosystems
During its site inspections, the Committee heard about the complex
hydrodynamics of the CLLMM system. The environmental management of the region
is further complicated by the mosaic of ecosystems within and surrounding the
region, including: mallee ecosystems; woodlands, including grassy and open
woodlands; peat swamp forests; freshwater, estuarine, coastal, and marine
ecosystems; and riverine ecosystems. The diverse range of ecosystem types necessitates
distinct management plans for each segment of the system.
It was noted that there is very little ecological resilience in the CLLMM
system, and that management strategies have therefore focused on increasing this
resilience to prepare for fluctuating levels of water availability. The
Committee heard about the South Australian Government’s Coorong Lower Lakes
Restoration Project, which also receives funding through the federal government’s
Water for the Future program. One of the goals of the restoration project is to
enhance the resilience of the region through extensive, community-based
revegetation programs. In 2012 the project will require 350 000 plants from 130
different local native species—including one nationally endangered.
As the Committee travelled around the region, it had the opportunity to see
some of these revegetation sites.
The aims of the extensive revegetation program are to reduce evaporation
and lower soil temperature, increase soil moisture, and remediate metals in the
soil. The program also helps ensure there is adequate, connected habitat to act
as refugia for local species during times of drought. Extensive planting
programs increase the organic carbon inputs into the system, encouraging the
activity of sulfate-reducing bacteria, thereby reducing acidity.
The Committee was informed that the DEWNR also treated acid sulfate
soils by applying limestone to neutralise some of the acidity. Engineering
solutions, such as reinforcing barrages, also help prevent saltwater
inundation, which would have profoundly negative effects on the ecosystems of
the CLLMM region.
The Committee also heard about localised interventions, such as those
employed when the creek at Wyndgate dried out and Murray hardyhead and Yarra
pygmy perch fish species declined. These species were captured, bred, and
released back into the repaired ecosystem. The Committee heard that these were
locally endemic species—biodiversity that would have been lost, had
intervention not occurred.
The Committee notes the complexities associated with environmental
management in the CLLMM region, and commends the extensive efforts to increase
the resilience of the system to future disturbances. The building of ecological
resilience is a worthy goal, given that the region is subject to variations in
weather and hydrological patterns, which are expected to be heightened by future
Examples of direct, urgent interventions to conserve biodiversity at
particular sites highlighted the importance of natural resource managers being
aware of the tipping points of species and ecosystems, and being prepared to
act quickly when needed. The Committee understands that such awareness requires
adequate resources for research and monitoring.
Community resilience through engagement and empowerment
The economic, social and cultural values in the CLLMM region depend on a
healthy and functioning wetland environment. In addition to enhancing
ecological resilience, as discussed above, the Committee heard about the
importance of building the resilience of local human communities. In the CLLMM
region, initiatives have improved communication and collaboration between
government and the local community, built environmental management capacity,
and encouraged citizen science.
As noted earlier, the Lakes Hubs at Milang and Meningie were established
to enhance collaboration between government and community members on
environmental restoration projects in the CLLMM region. The Committee heard
that the activities of the Hubs were very important, particularly at the height
of the drought, because they allowed members of the local communities to be
active participants in making decisions.
The Committee heard that there were some strong Landcare groups based in
the region, and that the local community was very supportive of revegetation
initiatives. The Lakes Hubs brought the communities and government agencies
closer together and enhanced two-way communication, making use of the local
The Committee was advised that resilience was also built by increasing
the community’s capacity to engage in environmental management programs. The
Community Advisory Panel (CAP) focuses on building the community’s resilience
to future drought episodes. Its membership is a broad range of 15 community
leaders, who are involved in strategic level planning, disseminating
information, and voicing community concerns. One of the outcomes of the CAP is
to build community ownership of environmental programs so that communities
carry on doing good work beyond the conclusion of government initiatives.
Programs carried out through the Lakes Hubs also helped create
opportunities to improve the economy of the region, particularly through job
creation and the provision of environmental management training. The native
plant species used in the extensive revegetation programs discussed above are
propagated and supplied by the Community Nurseries Network—a group of
commercial nurseries in the CLLMM region. Local non-government organisations
and community members have also been employed to deliver the revegetation
programs. In addition, funds have been invested in conservation and land
management training to increase natural resource management capacity in the region.
Many of the students from these training courses have subsequently been
employed by the Community Nurseries Network.
The Committee was informed that, in this region, the DEWNR had moved
away from the traditionally volunteer-based, government-owned approach to
natural resource management, and had instead redeployed many members of the
community who had lost their jobs in the local viticulture and dairy industries
as a result of environmental changes. These programs therefore delivered
environmental benefits, while also stimulating and transforming the local
economy, building resilience in the community, and ensuring local ownership of
The Committee heard briefly about a successful citizen science program
run in the area, also through the Lakes Hubs. A program to monitor acid sulfate
soils, overseen by the Commonwealth Scientific and Industrial Research
Organisation (CSIRO), provided the opportunity for 100 volunteers to be
trained to collect soil samples over a period of time, from various sites in
the region. The data were then fed back into the CSIRO’s data collection for
The Committee commends the approach taken by the DEWNR in the CLLMM
region, and notes the benefits of enhancing community resilience alongside
ecological restoration. Evidence received from community members suggested that
being part of the decision-making and implementation process had helped to empower
The Committee considers the Lakes Hubs a model for a successful
cooperative arrangement between government and the local community on issues of
biodiversity conservation, delivering ecological outcomes while improving
community resilience to future changes in the region.
Engaging Indigenous communities in biodiversity management
The CLLMM region and surrounding areas are the main homelands of the
Ngarrindjeri people, and are central to the culture and spiritual beliefs of
these Indigenous communities. Freshwater flows down the Murray‑Darling
system are seen as the lifeblood of the River Murray, Lower Lakes and Coorong, the
health of which is linked to the wellbeing of the Ngarrindjeri people. The
impacts of the drought were therefore significant for the Ngarrindjeri.
The Ngarrindjeri are committed to their country and have made
significant efforts over the years to be part of managing the region’s
environment. During inspections, the Committee heard about the DEWNR’s various
environmental management programs, delivered in conjunction with the
Ngarrindjeri community. Through engagement with the DEWNR, the Ngarrindjeri
have had input into ecological decisions. Such decisions may include ensuring
culturally appropriate plants are used in revegetation programs, for example, using
plants that attract totemic animals or are used in cultural practices.
The Committee was briefed on the Ngarrindjeri Regional Authority’s (NRA)
governance arrangements, put in place in 2007 to bring together the community,
voice the Ngarrindjeri’s concerns, and more effectively engage and negotiate
with other bodies. Cooperation between the NRA and State government is guided
by a whole-of-government Kungun Ngarrindjeri Yunnan Agreement (KNYA), made in
2009, which translates to ‘listening to Ngarrindjeri people talking agreement’.
The KNYA supports the full participation of the Ngarrindjeri in
government-led environmental management projects in the region. It also sets
out the rights and responsibilities of both parties to the agreement, and
ensures that the Ngarrindjeri’s cultural beliefs are considered in the
formulation of government programs in the region.
The Committee heard about some of the complexities associated with
intellectual property and copyright issues that came about during the
negotiation of the KNYA. Cultural knowledge clauses in the agreement have built
trust between the NRA and the government, and have given the Ngarrindjeri
confidence that Indigenous knowledge shared with government is not used
One of the key outcomes of the KNYA has been the establishment of the
Ngarrindjeri Partnerships Project by the DEWNR and NRA.
The project seeks to support participation in natural and cultural resource management
in the CLLMM region, and pledges long-term funding for regional environmental
programs in which the local Ngarrindjeri people will play a central role.
The Committee heard about a taskforce, established by the NRA and South
Australian Government, to build core capacities in the Ngarrindjeri community
through: training and skills development initiatives; increasing employment;
and encouraging effective engagement with government planning processes on land
and water management.
The NRA has established companies that employ members of the
Ngarrindjeri community. Such enterprise structures have enabled the
Ngarrindjeri to successfully tender for natural resource management contracts.
In turn, engaging in these initiatives provides training, knowledge and
experience to members of the community, and builds confidence in individuals to
engage in paid employment outside these structures.
The Committee was pleased to hear about the benefits of incorporating Indigenous
cultural considerations into environmental programs and policies. As advised by
DEWNR officers, meeting cultural considerations will always satisfy
environmental considerations as well, while an environmental approach alone will
not necessarily fulfil cultural requirements.
The Committee commends the DEWNR for building a cultural heritage
perspective into environmental programs, and for incorporating the expertise of
Traditional Owners in formulating biodiversity management initiatives.
The complexity of governance arrangements across state borders and
between various organisations was highlighted during the Committee’s
inspections of the CLLMM region. The Committee heard that the South Australian
Government had developed a long-term plan for the region, incorporating input
from community, scientists, industry, and other government stakeholders. The
long-term plan is part of the $610 million Murray Futures program, funded
by the Australian Government’s Water for the Future strategy.
It aims to secure a future for the region as a productive and resilient wetland
system of international importance, supporting the local economy and
communities that depend on a healthy environment.
However, the DEWNR’s plans for the region do not exist in isolation.
Commonwealth legislation, international agreements, the Murray–Darling Basin
Plan, and activities upstream in other states present challenges for the
governance framework supporting the environmental management of the CLLMM
Taking into account the unpredictable future climatic conditions and the
complex governance framework, the South Australian Government’s long-term plan
for the region proposes an adaptive approach to management.
The aim is to develop strategies that can respond to changing conditions, as
well as building ecological resilience into the region’s ecosystems. It is
intended that management strategies be informed by the best available science,
and that the outcomes of interventions be closely monitored.
Noting the complexities involved with natural resource management in the
CLLMM region, the Committee is pleased to note that there are plans in place to
address the region’s long-term needs. The South Australian Government’s
adoption of an adaptive approach to managing the ecosystems of the CLLMM region
supports evidence the Committee has heard elsewhere: that such an approach to
biodiversity management can deliver many benefits, particularly in the presence
of uncertainty. The Committee considers that an adaptive approach may be
relevant in many other parts of Australia, particularly as future climate
scenarios introduce elements of uncertainty into the complex ecosystems being
managed across the country.
Benefits of constructed wetlands in an urban environment
As noted earlier, the City of Salisbury’s Greenfields Wetlands project
is one of over 50 constructed wetlands within the local government area. During
its inspection, the Committee heard about the relevance of the wetlands to key
inquiry considerations, such as the sustainable use of resources, connectivity
between ecosystems, and promoting resilience in ecosystems.
The Greenfields Wetlands are located approximately one kilometre inland
from the sea, on a site that previously consisted of hypersaline soils. The
area is slightly below high tide level, which has historically made residential
and industrial development in the area problematic. Overdrawing from aquifers
in the area had also resulted in depleted reserves, risking saltwater intrusion
Figure 3.3 Part of the Greenfields Wetlands, City of
courtesy of committee secretariat
Constructed wetlands are a significant part of the City’s stormwater
recycling program. Urban stormwater run-off is treated in constructed wetlands
through a range of natural processes, including the filtering of larger
particles by riparian vegetation, aquatic plants and animals absorbing
nutrients and organic matter, the effect of sunlight and oxygen on bacteria,
and suspended clay particles settling on the bottom of the wetland. The
Committee heard that horizontal flow wetlands such as the Greenfields Wetlands
are able to remove approximately 90 per cent of pollutants and nutrients within
a 24 hour period.
Treated stormwater is then either distributed throughout the City,
mainly to government and industry consumers for irrigation and non-potable commercial
use, or stored in depleted underground aquifers during the wet season for later
use during the dry season.
The Committee was informed that one of the benefits of this system of wetlands
is the reduced demand on the River Murray and Mount Lofty Ranges catchments. Wetlands
also contribute to the City’s water sensitive urban design, and deliver
flood-mitigation services to local developments.
The Committee’s inspections highlighted the degree of connectivity
between terrestrial environments of the surrounding city, the freshwater
ecosystems of the wetlands, and the nearby estuarine and marine ecosystems. In
the past, untreated stormwater entering the Gulf St Vincent had resulted
in large meadows of seagrass dying off. These seagrass meadows had provided habitat
for important marine species and helped buffer the shoreline from tidal
Despite efforts to capture and re-use stormwater, most stormwater
run-off is still discharged into the Gulf St Vincent. To avoid damage to the
nearby marine ecosystem and important fish breeding habitats, the City of
Salisbury has therefore adopted a policy to clean all stormwater run-off before
it is released into the Barker Inlet, an estuary of the Gulf St Vincent. The
City’s key strategy in this regard is the use of wetlands to clean stormwater
before it is released into the Barker Inlet.
The inspections of the Greenfields Wetlands also underscored the
importance of constructed wetlands for increasing ecological resilience through
the provision of habitats for native plant and animal species. The Committee
heard about the many biodiversity benefits delivered by the wetlands, and the
careful planning that went into their design. For example, the inclusion of
‘beaches’ and hollow logs into the design of the wetlands has created habitats
for a range of bird populations. The City’s wetlands provide habitat for many
animal species, including numerous frog species, and aquatic macroinvertebrates
such as insects, crustaceans and worms.
Having inspected the CLLMM region the previous day, and having heard
about the stresses on the Murray–Darling system and the resultant adverse
impacts on the local environment and community, the Committee was mindful of
the need for sustainable water use and biodiversity conservation practices,
particularly in the context of a changing climate. During its inspection of the
Greenfields Wetlands, the Committee was pleased to hear about how urban
stormwater—traditionally regarded as a problem—can be managed and harnessed
through constructed wetlands. The Committee notes that such wetlands can
contribute to the sustainable use of water resources, enhance urban design,
deliver biodiversity benefits, and through the provision of recreational areas,
help engage the community on issues of biodiversity conservation.
The Committee notes that, since the time of its visit to South
Australia, the federal government has announced its support for other sustainable
stormwater harvesting and re-use projects around the country.
The Committee commends programs that seek to use natural resources in a
sustainable manner while supporting positive biodiversity outcomes.
The Committee’s site inspections in South Australia focused on
freshwater biodiversity and underlined the impacts of biodiversity loss on
human populations. The inspections also provided a worthwhile opportunity to witness
the benefits of communication, consultation and cooperation between governments
and local communities, engaging the public on issues of biodiversity
conservation, and utilising local expertise and insights. The Committee benefited
from seeing firsthand projects that provide simultaneously for the sustainable
use of natural resources and biodiversity conservation outcomes.
The Committee wishes to record its thanks to all the individuals it met
with during its site inspections in South Australia. The Committee extends its
appreciation to the South Australian Department of Environment, Water and
Natural Resources for its assistance, and in particular to Mr Russell
Seaman for facilitating the Committee’s visit and for his extensive briefings
throughout the site inspections in the CLLMM region. The Committee also
expresses its appreciation to Mr Colin Pitman from the City of Salisbury for providing
briefings and assisting with the Committee’s inspection of the Greenfields