Sandy Creek

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Vegetation

Riparian Habitat

iTRARC analysis of Riparian Habitat indicates that this subcatchment has undergone a very large decline in condition since the 1970s from good (B) to very poor (D). This has been due to clearing in the floodplains and riparian zones throughout this catchment. This has coincided with an increase in the erosion features in the landscape, leading to a decline in condition in many riparian zones in this area. The TRARC field survey supports this assessment with an overall score of C (poor condition) and only 1 of the four sites in good condition.

iTRARC Scores

Catchment Class 2 A
Maximum iTRARC Score 24 (A+)
1970s Score 11 (B)
2004 Score -5 (D)
Reduction in Ecosystem Services Very Large
Increase in Potential for Erosion Large
Reasons for Change in Score
  • Clearing of headwater streams including forest
  • Increased number of gaps on the main channel and anabranches
  • Loss of forest from anabranching reaches
  • Substantial floodplain clearing including forest
  • Increased floodplain bare soil and gullying/scalding

TRARC (field survey) scores

Survey SiteScoreRegenerationWeeds
Lagoon Ck46.4 (D)1 (C)0 (A)
Sandy Ck49.8 (C)2 (B)0 (A)
Monk Ck56.8 (C)1 (C)0 (A)
Beta Ck66.5 (B)2 (B)0 (A)
Average 54.9 (C)

Reference:Assessing the condition of Riparian Vegetation in the Burdekin catchment

Wetlands

This sub-division is poorly known ecologically, with even basic knowledge on the number and location of permanent or significant waterbodies, not recorded. The system here includes numerous channels and off-channel waterbodies, and waterholes present are likely to be highly and persistently turbid. Condition is not well known, but is considered likely to be similar to other sub-divisions in the region that are dominated by cattle grazing

Reference: Assessing the condition of Wetlands in the Burdekin catchment

For more information see Sandy Creek wetland condition summary

Water

SedNet Modelling of Water Quality

Model results for the Sandy Creek subcatchment are summarized as follows:

  • Subcatchment modelled area 3085 sq. km.
  • Source contributions: Hillslope = 56%; Gully = 34%; Streambank = 10%
  • Area of subcatchment with <50% ground cover: 1,327sq. km or 43% of subcatchment
  • Hillslope sediment supply: 134 kg/ha/yr
  • Total suspended sediment (flow weighted) supply: 74 kt/yr
  • Total suspended sediment supply (flow weighted; normalized to area): 239kg/ha/yr
  • Total suspended sediment end-of-subcatchment (flow weighted) yield: 55 kt/yr
  • Event Mean Concentration (EMC - flow weighted): 494 mg/L
  • Mean Annual Flow: 110,510 ML

Reference: Improved SedNet Modelling of Grazing Land in the Burdekin Catchment

Sandy Creek experiences low to moderate flow and receives low to moderate total suspended sediments. This results in a moderate event mean concentration of sediments and associated nutrients (494 mg/L) when compared to other Burdekin subcatchments. Low flow is a consequence of low annual rainfall in this area. Over half of the sediments washed into in the creek system derive from hillslope erosion. This may be due to the fact that just under half of the subcatchment (43%) has less than 50% ground cover. Gully erosion accounts for approximately one third of the sediment supply (31%).

Water Quality Monitoring

There are no water quality data available for this catchment.

Relevant information of Water Quality Monitoring in the Belyando River Basin:

Environmental Uses and Values

Aquatic Ecosystems

The aquatic ecosystem values of the Sandy Creek subcatchment are poorly known and, while considered to be Slightly to Moderately Disturbed (SMD) as a consequence of the surrounding land use for cattle grazing, the biological communities are thought to remain in a healthy condition and ecosystem integrity is likely to be largely retained. No High Ecological Value (HEV) waters have been identified in the subcatchment.

The Sandy Creek subcatchment is contained within the Desert Uplands bioregion except for a small section in the Brigalow Belt South bioregion. The condition of the waterways in this subcatchment is not known. Land cover is generally low, riparian condition is generally poor and erosion is widespread. Many areas of this subcatchment are susceptible to sheet and rill erosion. Cudmore National Park and the adjacent Cudmore Resources Reserve were suggested as areas that could be considered to be “effectively unmodified” (ANZECC 2000) and be identified as containing High Ecological Value (HEV) waters. However, there was too little information on the condition of the waterways in this area. This area warrants further investigation before a final decision on their HEV features is made.

Stock Watering

Water supply for production of healthy livestock.

Cultural and Spiritual

Custodial use of water by Bidjara traditional owners.

References:

Landuse

    Principle land uses within the Sandy Creek subcatchment as a proportion of total area:

  • Grazing: 94.5%
  • Conservation & minimal use: 5.5%
  • Water: Limited water use activity identified.

Grazing Land

Sandy Creek is a medium sized subcatchment where land use is dominated by grazing on natural and modified pastures.

Land Condition

Definition of ABCD land condition framework

Results of a Rapid Land Condition Assessment (adopted from Hassett et al. 2000) are presented below. The assessment has been devised to subjectively characterise condition while traversing the BDT region by vehicle. The data are based on a total of 4666 observations across the Burdekin region between 2004 and 2007.

The data were collected to provide independent information on land condition and provide a regional perspective. Resource assessment data are most useful when interpreted with other sources of data e.g. time-series remote sensing, modelling and water quality monitoring.

The estimated condition of the Sandy Creek sub-catchment is proportioned as follows:

  • A Condition: 11%
  • B Condition: 50%
  • C Condition: 39%
  • D Condition: n/a

Data from the Sandy Creek sub-catchment is based on 18 observations.

On the basis of the rapid assessment, the Sandy Creek sub-catchment is estimated to have the largest proportion of land in fair (B) condition (50%), followed by poor (C) condition (39%) and good (A) condition land (11%). Data not available for (D) condition land.

Ground Cover

Ground Cover in the Sandy Creek sub-catchment is proportioned as follows:

  • ( BC) Bare Cover: 0%
  • ( LC) Low Cover: 0%
  • ( MC) Moderate Cover: 72%
  • ( HC) High Cover: 28%
  • (VHC) Very High Cover:0%

Data from the Sandy Creek sub-catchment are based on 18 observations.

On the basis of the rapid assessment (2004-2007), the Sandy Creek sub-catchment is estimated to have the highest proportion of land within the moderate (MC) ground cover category (72%), followed by high (HC) cover (28%).

Resource Condition Summary

Sandy Creek is a medium sized subcatchment where land use is dominated by grazing on natural and modified pastures. Approximately 5% of the land area is set aside for conservation and minimal use. Riparian habitat in this subcatchment has undergone a major decline in condition over the last 30 years, principally as a result of widespread floodplain and riparian clearing along the main channel, anabranches and headwater streams, and is currently assessed to be in very poor (D) condition. The subcatchment waterways are poorly known ecologically, with even basic knowledge on the number and location of permanent or significant waterbodies not recorded. The waterways are understood to include numerous in-channel and off-channel waterbodies that are likely to be highly and persistently turbid.

Hillslope erosion is identified by models as the major source of sediment and particulate nutrients affecting water quality within Sandy Creek subcatchment, while gully erosion is also identified as a significant contributor to the total sediment load. The rate of soil loss is predicted to be quite low and below the Basin average, while the total amount of soil loss from the subcatchment to waterways is also comparatively low. Land condition is assessed as having a high proportions in fair (B) and poor (C) condition, while good (A) condition land is also apparent. This is also reflected in the rapid ground cover assessment (2004-07). Analysis of ground cover from satellite imagery indicates that the mean ground cover declined substantially from 1997 to 2006 and that areas of poor ground cover were common in 2006.

Water quality in the Sandy Creek subcatchment is predicted by models to be only slightly impacted by suspended sediment. There are no water quality monitoring data with which to compare the modelled concentrations and loads.

Draft Environmental Values

The aquatic ecosystem values of the Sand Creek subcatchment are poorly known and, while considered to be Slightly to Moderately Disturbed (SMD) as a consequence of the surrounding land use for cattle grazing, the biological communities are thought to remain in a healthy condition and ecosystem integrity is likely to be largely retained. No High Ecological Value (HEV) waters have been identified in the subcatchment. Little is known about the human use Environmental Values of the subcatchment, which are thought to be limited to use for stock watering, and the cultural and spiritual values of the Bidjara traditional owners.

Maps

References

SandyCreek.jpg
Download Catchment Layer as *.kml (requires Google Earth)

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