The Challenge

Poor water quality, caused by fine sediment and nutrients entering the Great Barrier Reef lagoon, have been shown to be the greatest threat to the Reef after climate change. The Burdekin River was reported to be responsible for delivering the highest volume of fine sediment of any river into the Great Barrier Reef. Areas of sodic or dispersive clays throughout the catchment were susceptible to erosion, particularly when groundcover is overgrazed, and the soils are exposed to heavy monsoonal rains during the wet season.

The catchments of the Bowen, Broken and Bogie rivers (BBB) were estimated to deliver around 50% of the fine sediment load to the Burdekin river mouth from only 9% of the total catchment area. This made the BBB catchment a focus for Greening Australia’s gully remediation works.

Kirknie Station, a grazing property on the banks of the Bogie and Burdekin rivers, had a number of alluvial gullies, estimated to have started 50 years ago.

The Solution

This project used a range of remediation techniques and ongoing grazing management to repair and stabilise three large alluvial gully complexes on Kirknie Station, to prevent 2,078 tonnes of sediment from entering the system annually.

Greening Australia’s delivery partner, Rock-It Science, developed plans to remediate the gullies by using best practice remediation techniques, including reshaping and battering the active gullies, installing rock chutes and bunds, and establishing vegetation to stabilise the works.

The landholders at Kirknie Station employed progressive grazing management practices, which helped ensure the long-term success of the gully remediation works.

Progress

On ground remediation works were completed from July to September 2022. The sites have revegetated and stabilised well. Some maintenance has been completed and one of the gullies will require further maintenance during the 2023 dry season. Overall, the remediation works were a success. By restoring the gullies at Kirknie Station we have stopped 2078 tonnes of sediment from entering the Great Barrier Reef each year.

This project was part of Greening Australia’s Reef Aid program, delivered in partnership with Rock-It Science and funded by the Great Barrier Reef Foundation’s partnership with the Australian Government’s Reef Trust. For more information, please feel free to send us an online query.