Last Chance done | Landholders Driving Change

A six metre deep gully had formed following the collapse of the stream bank at Three Mile Creek. PHOTO: Brooke Collett

Last eight projects completed

Eight projects that were approved under the last round of grants offered by the LDC project have been finalised.

The aim of the grants was to help graziers implement changes to better manage their land and businesses. Approved projects included fencing, piping and troughing, small gully remediation and whoa boy construction activities.

Projects received financial support in the range of $5000 to $25,000 through the LDC’s BBB Grazier Support activity area.

Key criteria included demonstrating how land condition and the water quality leaving the property would be improved. 

Applications were assessed by a panel consisting of a grazier (from outside of the BBB region), and NRM and government representatives.

There isn’t enough space to provide an overview of every project, however here’s a snapshot of works carried out on Todsure, at Scottville, near Collinsville.

Grazier Barry Collett shows the depth of the gully. PHOTO: Brooke Collett

An aerial view of where works were carried out at Todsure. Three Mile Creek is to the left.

Todsure:

Graziers: Barry and Brooke Collett

Barry is also a earthworks contractor and carried out the works himself, using his own machinery.

The problem:

The stream bank at Three Mile Creek collapsed about nine years ago, and over the years had formed a six-metre deep gully which was working back towards the homestead and other infrastructure. 

The soil is a texture contrast soil with several layers of sodic clays exposed. The topsoil is shallow, about 30cm. With no bedrock,  if left untreated, the erosion would continue to deepen and widen. The catchment for the gully is 33ha.

Treatment:

A 2.5ML dam was constructed higher in the catchment to capture upslope water. A 85m long bywash and a 310m long diversion bank were also constructed to protect the integrity of the dam wall and to spread water across the landscape.

The gully was shaped and battered during the dam construction. Following construction, the topsoil was spread over the dam wall to improve revegetation efforts. Exclusion fencing is also being installed.

Key Outcomes:

  • Stabilised, and reduced erosion.
  • Increased soil water-holding capacity.
  • Cattle will be excluded from the remediated area for a full wet season (from first rains to about April) to allow recovery of pasture and to allow the earthworks to stabilise. 
  • Cattle will only be grazed in the project paddock in the dry season based on a forage budget – match stocking rate with the carrying capacity of the land.
  • Monitor what is going on in the landscape and adjust grazing plan accordingly.

Todsure is a member of  LDC’s Scottville Cluster Group, which consists of six properties working together to address small-scale erosion issues on their properties. 

Click here for more information on the Scottville Cluster Group, and what Todsure achieved.

A 2.5ML dam has been constructed to capture upslope water and to protect the reshaped and battered gully.

Looking towards the dam bywash.

Dam bywash rock armouring to protect the integrity of the dam and dam wall.

LDC_s Rodger Walker and Todsure’s Barry Collett standing on the new dam wall.

Top of former gully (it was up to six metres deep, 90 metres long, and three to six metres wide) looking downstream to Three Mile Creek. A total of 0.7ha of reshaping works were undertaken.

Looking west across the former gully. Riparian exclusion fencing will be built.

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KEQ #1

Figure 1. Total fine sediment reduction by project type and erosion source. Inset shows the proportion of the total project area for each project type.

These estimates have been calculated using two methods: 

1) The pollutant reduction component of the Alluvium/Great Barrier Reef Foundation (GBRF) investment tool for hillslope and streambank erosion management projects; 

2) The Reef Trust Gully Toolbox method for gully erosion management projects. The LDC Water Quality Report 2020 (Waterhouse et al., 2020) highlights that a number of assumptions underlay these calculations, therefore these figures should be treated as the best available estimate of sediment reductions to date.

Preventing sediment from reaching the Great Barrier Reef

Each wet season sediment is washed into local waterways and out to the Great Barrier Reef (GBR). 

Most sediment is very fine, and can stay suspended for a long time and can travel great distances. Valuable topsoil is lost from production, and increased concentrations on the reef can be harmful to seagrasses and corals. 

Landholders in the BBB have completed 69 on-ground water quality practice changes, and it is estimated that these have contributed a fine sediment reduction of 6,154 tonnes per year from reaching the GBR. 

Of this, approximately half of the sediment savings are attributable to grazing land management changes on hillslopes and streambanks, and the other half as a result of gully remediation treatments across a broad range of scales, as shown in the graphs above. 

The table below also highlights the relatively small area of intervention in the gully management projects compared to the large sediment savings that these can achieve - 60 per cent of the sediment savings over only 4 per cent of the project area.

Table 1. Estimated sediment reductions (tonnes) from projects completed in the LDC Project to date.

KEQ #2

*GLMWW = Grazing Land Management Wire and Water

KEQ #3

*The Exploring New Incentives activity area has provided an opportunity for graziers to adopt improved land management practices through a range of activities. For some of these properties, it was the first time they signed contracts for on-ground works.

KEQ #4

The LDC project monitors four gully sites (represented in this table) with gold standard equipment and analysis, carried out by CSIRO.

Results have been compiled in a preliminary report from Bartley et al (2020), with the final report expected to be released by the end of 2020. The preliminary report shows all four sites have indicators of improvements, notably the Strathbogie and Mt Wickham sites.

KEQ #5

KEQ #6

KEQ #7
KEQ #8

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Reef regulations - grazing, standard conditions

  1. For land in good or fair condition (more than 50 per cent ground cover at 30 September), continue using measures to maintain land condition.
  2. For land in poor condition (less than 50 per cent ground cover at 30 September), steps must be taken to improve land condition.
  3. For land in degraded condition (less than 20 per cent ground cover at 30 September), steps must be taken to improve land condition OR prevent areas from further degrading or expanding.
  4. Keep records of measures taken and also of agricultural chemicals, fertiliser and mill mud or mill ash applied to land.
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