Hands-on action is turning the tide for South Australia’s rivers

Our waterways have faced significant challenges since European settlement, with invasive fish, pest plants and habitat degradation placing pressure on the river systems that we rely on for our economy, biodiversity and wellbeing. But thanks to sustained on-ground action and strong local partnerships, positive change is gaining momentum across the state. 

This World Rivers Day, we're celebrating some of the projects delivering real results for the long-term health of our rivers. 

Turning the tide against bottom feeders 

Since the 1970s, populations of European carp have become a major pest throughout Australia’s freshwater system. In fact, in some rivers, carp can make up as much as 90% of total fish biomass. 

Declared noxious under the Fisheries Management Act 2007, this invasive freshwater fish has turned our clear rivers a murky brown, eroded riverbanks and outcompeted native fish for habitat and food. They’re known as ‘water pigs’ for their vacuum-like riverbed foraging and ‘rabbits of the river’ for their ability to rapidly breed and overtake native aquatic ecosystems. 

A biological control, Cyprinid herpesvirus 3 that is present in overseas carp, is currently undergoing research for release in Australia. But in the meantime, one of South Australia’s landscape boards has turned to our wetlands as a way of tackling the issue. 

Murraylands and Riverland Landscape Board manages more than 120 wetland sites along the River Murray and uses targeted water management to improve wetland health and reduce the impact of carp. At selected sites, regulators are closed to disconnect the wetlands from the river, allowing water levels to fall. This drying process removes large carp and allows muddy sediments to consolidate. When the wetlands are refilled by reconnecting the wetland to the river, carp-exclusion screens prevent large carp from returning, while native fish and aquatic fauna can re-enter. 

The results can be dramatic. 

At Teal Flat Hut, a pool-connected wetland on the Murray River, this drying process has significantly improved the wetland’s turbidity – the clarity of the water. Testing the water for the ABC’s Landline program, Murraylands and Riverland Ecologist Amy Rice found an average turbidity reading of 4.5 in the wetland, while the reading in the adjacent river water was about 150. 

Clearer water allows aquatic vegetation to return - providing food and shelter for native species - and improves the wetland’s overall health.  

“It’s extremely rewarding in terms of all the work we’ve put into this,” said Amy. “Making sure there are no large-bodied carp remaining in the wetland during that dry phase and then coming out and seeing…that clear water and the benefits that it has not only to the wetland specifically but the surrounding areas.” 

View the Landline episode: Carp Removal: Clearing European carp from Murray River wetland

Creek transformed: A 30-year makeover of an urban waterway 

In Adelaide’s western suburbs, the final stage of the Breakout Creek / Purruna Pari redevelopment is showing how urban waterways can be transformed for both nature and the community. Delivered through a partnership led by Green Adelaide, the project marks the completion of a 30-year effort to restore the lower reaches of the River Torrens / Karrawirra Pari, reconnecting the river’s freshwater flows with the sea. 

The Stage 3 redevelopment has revitalised 15 hectares of previously fenced-off land, creating wetlands that capture and clean stormwater, removing weeds, and establishing more than 215,000 native plants. The works have created new habitat for fish, birds and other wildlife while helping to improve water quality before it reaches the ocean. 

Just as importantly, the project has opened the area for people to enjoy. New trails, river crossings, viewing platforms, picnic areas and spaces to learn about Kaurna culture have transformed the creek into a destination for recreation and connection with nature. 

Breakout Creek demonstrates how long-term investment, strong partnerships and ecological restoration can breathe new life into urban rivers, creating healthier waterways and communities at the same time. 

Locals band together to make a big difference 

In other parts of the state, community groups and landholders are showing that smaller scale efforts are an important piece of the broader puzzle of river recovery. 

At Cudlee Creek in the Adelaide Hills, neighbours from three adjacent properties have joined forces to deliver a coordinated revegetation project that spans 1.25 kilometres. 

Inspired by a shared vision to restore river health, Ashlee Wilton and Danny Mathew, Zipporah and Amos Maina, and John Stanley and Polihronia Kosmadopoulos are tackling invasive weeds and re-establishing native vegetation. 

The group successfully applied for Landscapes Hills and Fleurieu’s Grassroots Grants program as a collective, allowing them to scale their vision. Pooling resources has enabled them to engage professional contractors for mulching and weed spraying, laying the groundwork for the next stage - planting native tubestock. 

By improving plant diversity along the riverbanks, the project aims to build wildlife habitat, stabilise soils to reduce erosion, and lower fire risk. Over time, these efforts will help rebuild a more resilient and biodiverse ecosystem. 

Senior Stewardship Officer Will Hannaford said the project is a strong example of what can be achieved when neighbours work together.  

“By aligning their goals and sharing the workload, they’ve accelerated progress that would have been much harder to achieve individually,” he said.  “It’s a reminder that meaningful environmental change often starts at the local level with people willing to collaborate for the benefit of their land and community.”

Young people, muddy boots and big ideas along the Gawler River 

Meanwhile, a degraded stretch of the Gawler River at Hillier is being transformed through another community-led river restoration project that is improving river health while inspiring the next generation of environmental stewards. 

With support from the Northern and Yorke Landscape Board's Grassroots Grants Program, non-profit organisation The Emissaries (SA) Inc. is stabilising eroding riverbanks, removing invasive weeds and re-establishing native riparian vegetation along the river. 

More than 300 native plants have helped strengthen riverbanks, improve habitat for wildlife and reduce sediment flowing into the river, supporting healthier waterways across the catchment. 

A standout feature of the project is its focus on youth engagement, with young people gaining hands-on environmental learning and practical restoration skills through on-ground activities. 

The project’s spokesperson Cheyne Morris said restoring the river is about creating lasting benefits for both nature and the community. 

"We're not just planting vegetation. We're helping people, especially young people, build a connection with the river and understand their role in caring for it into the future," she says.  

Supported by $10,000 in Grassroots Grants funding and nearly $20,000 in in-kind contributions, the project demonstrates how local communities can work together to create healthier, more resilient rivers.

From the classroom to the riverbank 

Yet another community group is set to roll up their sleeves for river health, this time on Eyre Peninsula. Grassroots Grants funding from the Eyre Peninsula Landscape Board will allow Navigator College to restore a 1 km section of the Tod River, situated inland from Port Lincoln. Through targeted weed control and revegetation, the school aims to reduce erosion and strengthen student connection to Country.

Working together for heathier rivers 

From restoring native vegetation and reducing erosion to improving water quality, the impact of river restoration extends far beyond individual project sites.

While every river is different, these success stories demonstrate the power of local action to deliver statewide benefits. By working collaboratively, South Australians are helping to protect natural assets, strengthen resilience to future environmental challenges and create lasting benefits for generations to come.