Issue: Catchment quality
How has catchment quality changed?
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See these indicator results for more detail: | Discharges to waters | Ecological communities | Fire | Groundwater | Land degradation | Landuse | Pest plants | Riparian condition |Surface water quality | Water use |
Lupin crop in Young Shire
Insufficient data were available to adequately assess changes to, or impacts on, many aspects of catchment quality within Young Shire during the reporting period. As a result, changes in erosion, salinity, ground and surface water quality and condition of terrestrial and riparian ecosystems and impacts of these changes could not be reported .
Drought was potentially the most significant event impacting on catchment quality within the shire during the reporting period. The entire shire was drought-affected during late 2002 to late 2003 and early to mid 2004. Parts of the Bland and Burrangong Creek subcatchments suffered drought in addition to these periods. The drought continued beyond the end of the reporting period.
Potential effects of drought included:
- in all subcatchments—increased erosion, reduced vegetation vigour and increased pressure on native vegetation, increased environmental stress on waterways
- in all subcatchments—a shift from grazing and mixed farming to cropping
- in all subcatchments—decreased areas of infestation of Wild Radish
- in all subcatchments in areas of native vegetation—increased fire risk
- in all subcatchments—increased stress on riparian ecosystems due to lack of flow in watercourses
- in all subcatchments—increased pressure on surface and ground water resources
- in the Burrangong River subcatchment—decreased volumes of water reaching the Young Sewage Treatment Works. This is tempered by the fact that council only allows minimal flows into the watercourse through effluent re-use practises.
Again, impacts were not known at the end of the reporting period.
Where are the 'hot spots'?
During the drought periods, the Bland Creek subcatchment had a more reduced vegetation vigour from October to November 2003 than other subcatchments within the shire and the Burrangong and Crowther Creek subcatchments had a more reduced vegetation vigour from December 2003 to January 2004.
An amount of treated effluent from the Young township is discharged into the Burrangong River. No information regarding the impacts of this on catchment quality was available, however it should be minimal due to the effluent meeting licence targets.
Despite the drought, severe to extreme dryland salinity outbreaks were reported in the Burrangong and Crowther Creek subcatchments.
Extreme gully erosion predominantly recorded along the catchment boundary between Crowther and Burrangong Creek subcatchments and in the eastern section of the Crowther Creek subcatchment from Stringybark Flat to Koorawatha. Severe to extreme sheet erosion predominantly occurs within the Burrangong Creek subcatchment with some areas in the upper Crowther Creek subcatchment.
The only areas of timber production forests within the shire occur in the Douglas Range and at Mount Crowther in the Crowther Creek subcatchment.
Three out of four priority pest animals within the shire were recorded within the Crowther Creek subcatchment i.e. Rabbits, Wild Deer and Goats. Rabbits decreased while the latter two remained stable during the reporting period. The main infestation of Silverleaf Nightshade occurs in the Young area within the Burrangong River subcatchment. The area of infestation of this species remained stable during the reporting period.
Strongly acidic soils occur throughout the majority of the Crowther, Balabla and Jones Creek subcatchments. A small area of agricultural lands in the upper Crowther Creek subcatchment and a large area in the upper Bland Creek subcatchment were not in this class but had a high to critical risk of soil acidification. Impacts of acid soils may include decreased crop yields, poor performance of perennial pastures, and increased erosion, siltation and salinity. These impacts may, however, be ameliorated through good land management practices.
Other factors relating to catchment quality
The only conservation reserves within the shire are within the Crowther Creek catchment on the Dananbilla–Illunie Range and at Koorawatha. The latter reserve was dedicated during the reporting period and substantial additions were also made to the reserve at Dananbilla.
A number of vegetation communities within the shire were estimated to be endangered or vulnerable.
A number of small wildfires occurred within the shire during the reporting period. It is unknown where these were located or what impacts they had on catchment quality.
All priority weed species either remained stable or experienced reductions in area during the reporting period.
What has been done to address catchment quality?
At least five projects were undertaken by community groups and council to improve catchment quality within the Burrangong Creek subcatchment. Activities undertaken included native vegetation protection, revegetation, riparian fencing and salinity works. At least another three projects were undertaken in Bland Creek subcatchment to protect and enhance native vegetation. In addition, at least another three projects in the Crowther Creek subcatchment were undertaken to address salinity, erosion and vegetation decline .
Activities undertaken by council during the reporting period to address catchment quality include:
- reuse of treated effluent from the Young Sewage Treatment works on the Golf Course
- council, Department of Primary Industries and Natural Heritage Trust funded weed control for all priority pest plants within the shire resulting in reductions in all species
- introduction of water restrictions during drought periods.
Activities undertaken by the Young Rural Lands Protection Board reduced rabbit populations within the shire.
Other actions to conserve biodiversity would have contributed to catchment quality within the shire (see Conserving biodiversity issue).
The future—what does this mean for Council?
Continued lack of data about many aspects of catchment quality within the shire will mean only partial assessment of it is possible, and with it, a corresponding risk of activities within the shire having inadvertent adverse impacts.
Lack of ongoing monitoring of erosion, sedimentation, salinity and ground and surface water quality within the shire may hamper conservation efforts, as impacts from urban and rural development and other pressures (e.g. fire, drought, landuse) cannot be determined and remediation measures cannot be planned. Monitoring is also essential to determine whether environmental plans and strategies and on-ground management projects are achieving the desired catchment management outcomes.
Council needs to maintain appropriate effort and resources in the following areas of its environmental management.
- Ensure impacts on catchment quality are considered in landuse zoning, assessment of development applications, road management, water supply works, waste water management and riparian revegetation or rehabilitation projects. These activities need to include consideration of land capabilities and potential impacts on ground and surface water quality.
- Work towards achieving appropriate monitoring programs are in place to measure the effectiveness of council's environmental policies, strategies, management activities and on-ground restoration projects in achieving desired land and water management outcomes where feasible.
- Support and encourage community involvement in sustainable land and water management and monitoring.
- Maintain close liaison with NSW State Government agencies to encourage programs of data collection, especially for monitoring soil loss and erosion, salinity, sustainable land and water management systems and to help ensure Council has up-to-date knowledge about the condition of the shire's catchments and associated management issues relevant to them.
- Work closely with the Lachlan Catchment Management Authority to help ensure consistency in approach to catchment-scale land and water management and complementary actions to achieve this.