Mambo Wetlands ~ at what cost?
Council has plans for Port Stephens as an Eco Destination.
Where does Mambo Wetlands fit in?
By Iain Watt
11 August 2026
Iain Watt is a Marine Scientist, President of EcoNetwork Port Stephens, instigator of the Port Stephens Eco Destination forum, a member of Council’s Environment Advisory Group (EAG) and Port Stephens Great Lakes Marine Parks Advisory Committee.
This is the speech Iain presented at the Council Meeting on 11th August where Councillors discussed the Agenda for the August 25th Council Meeting for which amendments to the Salamander Town Centre Place Plan will be decided.
Thank you to Council for reviewing the Salamander Bay Place Plan considering its impact on the Mambo Wetlands, and for backing the Destination Eco-Accreditation initiative.
This is an important step forward for an LGA whose economy depends on $700 million a year in domestic and international nature-based tourism.
What price our natural environment?
Our natural assets, wetlands, koalas, and dolphins are not just amenities — they’re productive assets and like any other assets, need protecting. Property values, tourism, fisheries, the retirement sector, and Council’s own revenue all depend on them. Eco-accreditation while an important move forward only works if it’s backed by genuine environmental primacy — the environment placed ahead of development — otherwise it’s just complex marketing or greenwashing.
Does Council have the power to implement environmental primacy?
Yes, council already has the authority to implement environmental primacy. The EP&A Act and the NSW Biodiversity Conservation Act give Council binding obligations: to protect the environment, particularly where development threatens significant ecological values; council assessment can mean refusal, redesign, or conditions that fundamentally change a project. Council can set binding environmental standards through the LEP,(Local environment Plan), and DCPs, (Development Control Plans).
Environmental Primacy is not a new concept.
The City of Sydney mandated a 15% tree canopy cover within ten years through this process, requiring developers to meet this standard. Our planning process should reflect these powers, not treat the environment as a hurdle to clear. This is not anti-development. Our economy is a direct expression of our ecology, not separate from it. Environmental primacy is not a constraint on prosperity — it is a precondition.
Port Stephens is not being asked to invent environmental primacy, it’s being asked to adopt tools that are already proven in comparable coastal and tourism economies. In Port Stephens we keep testing the cost of not adhering to environmental primacy one wetland and natural asset at a time.
Is Mambo Wetland’s buffer zone a degraded wetland?
No part of the Mambo Wetlands and its buffer zone can legitimately be termed as wasteland; it can and will recover however degraded. Research has valued wetlands’ contributions to fisheries alone at $86,459 per hectare per year on the value of the wetland. The best farmland in this region sells for around $13,100 per hectare, a one off sale. Intact wetland outperforms farmland earnings many times over through ecosystem services (flood and pollution control, sediment settlement, carbon sequestration, amenity value), in perpetuity, without ever being sold.
Port Stephens has lost at least 20% of its saltmarsh in the past 15 years. Every hectare of wetland still under development pressure makes that situation worse. We cannot keep taking ecosystem services for granted while diminishing the asset. Selling off wetland and other natural assets is not a solution for the future, merely an easy out for the present.
Part of the problem is that development decisions in Port Stephens are being made without adequate ecological consideration. Development envelopes are being drawn before ecological ones and profits imagined before their impacts.
What’s the value of Mambo wetlands?
In 2016 the State sold 5.6 hectares of Mambo Wetlands for $250,000 despite resistance from the local council and community. After a three-year campaign — a 10,000-signature petition and with unanimous Council support for buy back, the State bought it back in 2019 for $420,000: effectively a $170,000 loss in 3 years. We don’t want to repeat that.
The community has been pushing for Ramsar recognition of Mambo Wetlands for the past 10 years or more and it remains unresolved. In 2023 council agreed to investigate the process but noted that it would cost $150,000 annually. That’s a rounding error against what this site delivers in ecosystem services, and it can probably be offset within its existing maintenance budget. This site should be Ramsar-listed, its management plan updated, and its upkeep formally funded.
Mambo operates as a large drainage catchment taking all the polluted run off from the Salamander shopping centre carpark and depositing it in the estuary as relatively clean water. What would it cost to replace what Mambo does for free? No site-specific study exists, itself part of the problem, but comparable municipal studies suggest replacing just its drainage and flood function with built infrastructure would run into the tens of millions, in addition to massive ongoing maintenance costs. That figure captures none of the other benefits, fisheries, koala habitat, urban cooling, water filtration and community amenity that the wetland provides for nothing.
This site matters beyond economics. It cools the surrounding urban area and with better paths, it could become a fully accessible natural space for all residents including the elderly and disabled, and for the day care and schools already using it to teach children about the natural world. A recent walk through the area revealed a Day Care project identifying that “ants live here” an important learning opportunity. Research shows exposure to real, biodiverse green space, trees — not mown grass, measurably reduces psychological distress. This is a recognised and growing medical problem, increasing the importance and value sites like Mambo will have for the future community.
Why are buffer zones important?
A wetland’s boundary isn’t its functional edge. It has been widely demonstrated that when the buffer zones are degraded the core habitat, in this case, the wetlands themselves become degraded, directly impacted by peripheral activities (such as development, pollution, fire etc.) and the edge effect.
The “edge effect” results in habitat being degraded well beyond the apparent designated boundary. Wind, light, weeds, and predators penetrate inward, favouring generalist and invasive species over the more sensitive natural biota. A development approved to the edge of a habitat boundary therefore degrades more than its footprint suggests, which is exactly why mandatory buffer zones — not just a line on a plan — are necessary to protect what remains.
It is as critical to protect the buffer zone as it is to protect the core habitat. A plan that only measures direct habitat loss will fail to protect what it claims to be saving.
The original Place Plan recognises none of the ecological, social or economical values, and risks the collapse of Mambo Wetland collapse.
This isn’t politics, and it isn’t really about developers. It’s about the community, every family and their future generations will benefit from a protected well-managed Mambo Wetland.
It’s time to decide, once and for all, what this asset is really worth to us and protect it accordingly, before we lose it to negligence, or worse.
All slides from the presentation can be downloaded here (4.1Mb)