Pelican Creek

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Subcatchments

Smaller subcatchments within the Pelican Creek Catchment include:

  • Flagstone Creek
  • Pelican Creek
  • Strathmore Creek

Vegetation

Riparian Habitat

iTRARC analysis of Riparian Habitat indicates that this subcatchment has undergone a large decrease in riparian condition in the last 30 years. In the 1970s it was in good (B+) condition but had dropped to poor condition (C) by 2004 due to floodplain clearing and an increase in the amount of gullying/scalding. The field survey TRARC data also indicated very poor condition at both sites visited, however additional sites would provide a more comprehensive picture of on-ground riparian condition.

iTRARC Scores

Catchment Class 2 D
Maximum iTRARC Score 22 (A+)
1970s Score 13 (B+)
2004 Score 3 (C)
Reduction in Ecosystem Services Large
Increase in Potential for Erosion Large
Reasons for Change in Score
  • Increased number and % of gaps in the headwaters
  • Extensive floodplain clearing including forests
  • Increase in the amount of bare soil on the floodplain
  • Large increase in the amount of gullying/scalding

TRARC (field survey) scores

Survey SiteScoreRegenerationWeeds
Strathmore Ck44.3 (D)1 (C)1 sp: 40% cover (C)
Pelican Ck51 (C)2 (B)4 spp: 16% cover (D)
Average 47.7 (D)

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

Wetlands

Pelican Creek is a seasonal creek system that contains several permanent waterholes, the limnology of one of which, Donalds Dream Waterhole, was assessed by Loong et al. (2005). The water quality of Pelican Creek is adversely affected by coal mining operations in its upper reaches (Butler 2006). Riparian condition is considered to be reasonable though. Strathmore Creek is naturally dry but runs for many kilometres with seepage from the coal mine tailings dam (pers. obs.), producing an altered flow regime and altered water quality (including high conductivity water and salt stains along the creek). Both creeks have been subject to water quality and aquatic biota monitoring programs commissioned by the mine managers. Other creeks not affected by mining operations appear to be typical of the region.

Reference: Assessing the condition of Wetlands in the Burdekin catchment

For more information see Pelican Creek wetland condition summary

Water

SedNet Modelling of Water Quality

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

  • Subcatchment modelled area: 1,452 sq. km.
  • Source contributions: Hillslope = 85%; Gully = 8%; Streambank = 7%
  • Area of subcatchment with <50% ground cover: 450 sq. km or 31% of subcatchment
  • Hillslope sediment supply: 865 kg/ha/yr
  • Total suspended sediment (flow weighted) supply: 147 kt/yr
  • Total suspended sediment supply (flow weighted; normalized to area): 1,012kg/ha/yr
  • Total suspended sediment end-of-subcatchment (flow weighted) yield: 137 kt/yr
  • Event Mean Concentration (EMC - flow weighted): 850 mg/L
  • Mean Annual Flow: 161,268 ML

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

Hillslope erosion is identified as the major source of sediment and particulate nutrients affecting water quality within the Pelican Creek sub-catchment (85%). It is estimated that approximately 31% of the subcatchment has poor ground cover (<50%). Total suspended sediment loss from all sources is predicted to be very high (1,012 kg/ha/yr). The event mean concentration of suspended sediment is also predicted to be high (850 mg/L).

Water Quality Monitoring

Limited water quality monitoring in the Pelican Creek catchment does not permit useful conclusions to be drawn.

Relevant information of Water Quality Monitoring in the Bowen Broken Bogie River Basin:

Environmental Uses and Values

Aquatic Ecosystems

The aquatic ecosystem values of an area in the Pelican Creek watershed, above Collinsville, has been identified as containing High Ecological Value (HEV) waters by technical experts and workshops. This area, covering the Sonoma State Forest, is in the north-east part of the subcatchment. The Sonoma State Forest is a large area consisting of rugged rocky outcrops on steep hills. The area is crossed by several tracks and a power line but appears largely intact and in a natural state. The area of remnant forest is contiguous with other natural areas in the Clarke Ranges going north and west into the upper Bogie River subcatchment and east to the rainforests in the upper Broken River. The aquatic ecosystem values of Pelican Creek below Collinsville is considered to be Highly Disturbed (HD) as a consequence of the surrounding land use, particularly mining, and flow modification.

Pelican Creek is a season tributary system of the Bowen River. Rainfall through the subcatchment ranges between 600mm on the lower, western part of the catchment to above 900mm in the Clarke Ranges in the upper, north-eastern sections of the subcatchment. The water quality in much of Pelican Creek is affected by the township of Collinsville and the operations of nearby coal mines.

As well as the effects of mining operations, floodplain clearing and gully erosion is reported to be widespread throughout the subcatchment. However, an area in the upper catchment above Collinsville was assessed by the WQIP ecological values technical panel to be “effectively unmodified” (ANZECC 2000) and have been identified as containing High Ecological Value (HEV) waters. The area selected was the Sonoma State Forest, in the north-east part of the subcatchment adjacent to the Bowen-Collinsville Road and abuts the Bogie River subcatchment. Adjacent areas in the upper catchment areas to the east of Sonoma State Forest may also contain HEV waters but require further investigation to confirm their condition.

The Sonoma State Forest is a large area consisting of rugged rocky outcrops on steep hills. The area is crossed by several tracks and a power line but appears largely intact and in a natural state. The area of remnant forest is contiguous with other natural areas in the Clarke Ranges going north and west into the upper Bogie River subcatchment and east to the rainforests in the upper Broken River catchment. The permanence of water during the dry season is not known. Little is known about the ecology of the streams and water bodies in the area. But it appears that creek would be known at this stage. Not much appears to be known about the fauna and flora of the area. It contains the ‘of concern’ regional ecosystems Eucalyptus crebra, E. tereticornis, Angophora leiocarpa woodland on igneous rocks especially granite (RE 11.12.3) and is noted for the presence of the Koala, Phascolarctos cinereus.

Irrigation

Irrigation of improved pasture dominates (over 80% of irrigation water use) with relatively minor areas of sorghum and horticulture.

Stock Watering

Water supply for production of healthy livestock.

Drinking Water

Town water for Collinsville supplied from the the Gattonvale Offstream Storage (and the Bowen River Weir).

Industrial Uses

Scottville open cut coal mine. There are some potential additional demands around Scottville and Collinsville for industrial use of water including those for possible expansions in power generation and for coal mining.

Cultural and Spiritual

Custodial use of water resources by Birri and Gia traditional owners.

References:

Landuse

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

  • Grazing: 96.4%
  • Mining: 2.6%
  • Conservation & minimal use: 1.2%
  • Irrigated horticulture & cropping: Limited irrigated horticulture & cropping water activity use identified.
  • Water: Limited water activity use identified.
  • Urban & semi urban: Limited urban & semi urban water activity use identified.

Grazing Land

Pelican Creek is a relatively small subcatchment where the major land use is grazing on natural 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 Pelican Creek sub-catchment is proportioned as follows:

  • A Condition: 2%
  • B Condition: 28%
  • C Condition: 52%
  • D Condition: 18%

Data from the Pelican Creek sub-catchment is based on 99 observations.

On the basis of the rapid assessment, the Pelican Creek sub-catchment is estimated to have the largest proportion of land in poor (C) condition (52%), followed by fair (B) condition (28%) and very poor (D) condition land (18%). 2% of observed land was in good (A) condition.

Ground Cover

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

  • ( BC) Bare Cover: 2%
  • ( LC) Low Cover: 27%
  • ( MC) Moderate Cover: 45%
  • ( HC) High Cover: 25%
  • (VHC) Very High Cover: 2%

Data from the Pelican Creek sub-catchment are based on 64 observations.

On the basis of the rapid assessment (2004-2007), the Pelican Creek sub-catchment is estimated to have the highest proportion of land within the moderate (MC) ground cover category (45%), followed by low (LC) cover (27%) and high (HC) cover (25%) categories. 2% of land was estimated to fall into the very high (VHC) and bare cover (BC) category.

Resource Condition Summary

Pelican Creek is a relatively small subcatchment where the major land use is grazing on natural pastures. Mining is also identified as an important land use in the subcatchment. The condition of riparian habitat in the subcatchment has declined over the last 30 years due to floodplain clearing and gullying. The catchment was in fair (B) condition in the 1970s, but by 2004 its condition had declined to poor (C). Pelican Creek itself is a seasonal creek system that contains several permanent waterholes, but the water quality is adversely affected by coal mining operations in its upper reaches. Strathmore Creek, which is naturally dry, is affected by seepage from a coal mine tailings dam, thus producing an altered flow regime and altered water quality. This system has a greater departure from natural conditions than most other creeks in the area and in the Burdekin rangelands.

Hillslope erosion is identified by models as the major source of sediment and particulate nutrients affecting water quality within the Pelican Creek subcatchment. The rate of soil erosion is predicted to be high and only slightly above the Basin average, while the total soil loss from the subcatchment to waterways is moderately high compared to other basin subcatchments. Land condition is assessed as having the highest proportion in poor (C) condition, with substantial areas of fair (B) and very poor (D) condition land apparent. This is also reflected in the rapid ground cover assessment (2004-07). Analyses of ground cover from satellite imagery (reference) identify Strathmore Creek as having a particularly high density of land that is both marginal and vulnerable to 'D' condition. While the mean ground cover over the entire subcatchment declined substantially from 92% in 1999 to 63% in 2004, it had recovered to 83% in 2006.

Water quality in the Pelican Creek subcatchment is predicted by models to be very poor, with high concentrations of sediment at end-of-subcatchment. There are no water quality monitoring data, however, with which to compare the modelled concentrations. On the basis of the land condition and ground cover assessments, verification of modelling should be undertaken as a priority.

Pelican Creek is identified as a priority subcatchment for rehabilitation on the basis of its marginal and vulnerable 'D' condition land, high rate of soil erosion and predicted contribution to the total sediment load within the basin.

Draft Environmental Values

An area in the Pelican Creek watershed, above Collinsville, has been identified as containing High Ecological Value (HEV) waters by the BWQIP ecological values technical panel. This area, covering the Sonoma State Forest, is in the north-east part of the subcatchment. The Sonoma State Forest is a large area consisting of rugged rocky outcrops on steep hills. The area is crossed by several tracks and a power line but appears largely intact and in a natural state. The area of remnant forest is contiguous with other natural areas in the Clarke Ranges going north and west into the upper Bogie River subcatchment and east to the rainforests in the upper Broken River. The aquatic ecosystem values of Pelican Creek below Collinsville is considered to be Highly Disturbed (HD) as a consequence of the surrounding land use, particularly mining, and flow modification. The human use Environmental Values of Broken River subcatchment are understood to include irrigation, industry, stock watering, drinking, and the cultural and spiritual values of the Birri and Gia traditional owners.

Maps

References

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

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