Reducing the volume of sediment entering Moreton Bay and improving rural communities’ flood resilience.
The Healthy Catchments program delivers stream bank and gully stabilisation projects in areas identified as contributing high sediment loads to Ramsar listed Moreton Bay.
Gully and streambank projects control erosion, improve bank stability and water quality by reducing sediment and turbidity in waterways.
Projects include small-scale gully repairs through to large-scale gully and instream engineering works, early interventions and involving and educating landholders in identifying erosion risks.
Reaches of the upper Bremer, Upper Warrill and Upper Laidley sub-catchments were identified as the largest contributors of sediment in Moreton Bay in a 2010 joint Healthy Land and Water and Griffith University study.
There have been multiple iterations of the program since 2010 and the program is currently in its fourth phase. During that time works have been delivered in focus areas across the region, in the upper reaches of the Lockyer, Bremer, Logan and Albert catchments.
The focus of each iteration of the program has evolved over time. Earlier works had a focus on larger engineering projects such as log jams to stabilise eroding banks on major waterways, while currently a higher number of smaller scale gully erosion projects are being delivered.
About the project
- Reducing sediment and improving water quality.
- Protecting agricultural land and environmental values by reducing gully and streambank erosion.
- Between 10,000 and 12,000 tonnes of sediment have been prevented from polluting waterways each year.
- Work has been delivered in the Upper Laidley, Bremer, Warrill and Mid Brisbane sub-catchments.
Why this project is important
Streambank and gully erosion is a major source of sediment entering our waterways and previous studies have identified the Upper Warrill, Upper Bremer, and Upper Laidley catchments as contributing high sediment loads to Moreton Bay.
Accordingly, the program has focused on gully and in-stream bank stabilisation projects to reduce sediment and improve water quality in these priority areas. This phase of the program has also extended to include the Mid-Brisbane sub-catchment.
Keeping sediment in the landscape and slowing the water flow in the upper catchments prevents it from being mobilised into waterways, causing damage and endangering the ecosystems downstream through to Moreton Bay.
Reducing streambank and gully erosion protects productive agricultural land and through targeted vegetation planting can also increase bank stabilisation, rain infiltration, reduce surface runoff and provide a stable area for sediment deposition, improving environmental outcomes for landholders.
- Repairing gullies and streambanks using engineered solutions, such as leaky weirs, rock chutes, walls and revetments.
- Creating ‘refuge gullies’ around these structures with targeted vegetation planting with the objective of increasing canopy cover to 20-30%.
- Landholder education including field days focused identifying risks, how to prevent major gully systems forming as well as how to design and undertake small scale gully repair on their properties.
- Maintaining past streambank and gully repair project sites.
- Previous project phases have successfully stabilised 3.8km of creek and gully banks with earthworks, revegetation, and weed control.
- Six large instream projects were completed across the various sub-catchments.
- Recent assessments have shown that between 10,000 and 12,000 tonnes of sediment have been prevented from polluting waterways each year as a direct result of the Healthy Catchments Program.
- Phase four of the project will focus on repairing gully erosion sites across the Upper Laidley, Bremer, Warrill and Mid-Brisbane sub-catchments, paired with establishment of a vegetated buffer area called ‘refuge gullies’ and landholder education.
- Improve rural community flood resilience and reduce the risk to agricultural assets through the stabilisation of eroding creek and gully banks.
- Improve landholder awareness and skills through a series of field days that focus on the key fundamentals of identifying erosion risks, erosion prevention activities and how to design and construct small scale gully remediation projects on their own land.
A Healthy Land and Water project, in collaboration with the Queensland Government’s Department of Environment and Science.