What the results tell us for Snowy River
No quantitative information was available to assess change in riparian condition within the shire during the current reporting period. During that period, five threatening processes which impact on riparian condition were listed under the Threatened Species Conservation Act 1995 and the Fisheries Management Act 1994.
Council and community groups undertook at least 10 projects between July 2000 and June 2004 to rehabilitate riparian areas within the shire. Fencing of the riparian zone appears inadvertently to have resulted in a proliferation of weeds there and resulted in these zones becoming a key source of propagules for the spread of at least two priority pest plant species in the shire.
Condition of riparian zones in the shire
During the previous reporting period, Bobundra Creek, Kara Creek, Mattong Creek to Stoney Creek, Mowamba River, Reedy Creek and Wullwye Creek, all within the Snowy and Genoa catchment, were reported to have a high to medium stress rating with respect to riparian vegetation and stream geomorphology. Over that time, Jacobs River to Pinch Creek was the only stream within the shire reported to have a low stress rating for these factors. Stress ratings for riparian vegetation and stream geomorphology were not assessed for rivers within the Murrumbidgee River catchment for the previous reporting period (OCE 2000).
The extent to which the condition of riparian vegetation, channel modification and streambank disturbance across the shire changed in the current reporting period is not known, as no comprehensive assessment of riparian condition was undertaken.
Council reports that while fencing of the riparian zone has probably lead to improvements in water quality and reduction of bank erosion, it has also resulted in a proliferation of weeds within the zone (Clarke 2005). With the exception of willows (Salix spp) and blackberry (Rubus spp), where targeted control programs have been undertaken, riparian weeds increased during the current reporting period. The riparian zone is now one of the key sources of propagules for the spread of weeds such as Serrated Tussock (Nassella trichotoma) and African Lovegrass (Eragrostis curvula) (Clarke 2005).
Threats to riparian condition
Two processes relating to riparian condition have been listed as key threatening processes in the state (see Table 1) by the NSW Scientific Committee under the Threatened Species Conservation Act 1995. Final determinations for both of these were made during the current reporting period. During the same period the NSW Fisheries Scientific Committee also listed, under the Fisheries Management Act 1994, three key threatening processes relevant to riparian areas (Table 1).
|Name of threatening process||Date of final determination or gazettal|
|Alteration to the natural flow regimes of rivers, streams, floodplains and wetlands (DEC 2005a)||Final: 31 May 2002|
|Clearing of native vegetation (DEC 2005b)||Final: 21 September 2001|
|Degradation of native riparian vegetation along NSW watercourses (DPI 2005a)||Gazetted: 16 November 2001|
|Installation and operation of instream structures and other mechanisms that alter the natural flow regimes of rivers and streams (DPI 2005b)||Gazetted: 24 May 2002|
|Removal of large woody debris (DPI 2005c)||Gazetted: 2 November 2001|
The impacts of these key threatening processes on riparian condition and waterways include (DEC 2005a, b; DPI 2005a–c):
- bank erosion
- impairment of important ecosystem services for fish and invertebrates (e.g. removal of refuges used during flooding or drought or removal of spawning sites)
- reduced nutrient filtering capacity
- increased light penetration of the waterbody and loss of shade and shelter for fish
- reduced inputs of organic carbon (e.g. twigs, leaves etc)
- changes to stream behaviour.
What is being done to protect riparian zones?
Council reports (Clarke 2005) that during the current reporting period extensive work was undertaken through Landcare and Catchment Management Authorities (CMAs) to restore riparian vegetation within the shire. A selection of projects undertaken by community groups, council or other organisations that enhanced riparian condition is shown in Table 2.
The Snowy River Restoration Project undertaken by the CMA achieved many kilometres of willow control within the catchment. The Southern Rivers CMA undertook an additional project for weed control along the Snowy River; council assisted by liaising with landholders regarding incentives, follow-up, inspection and regulation (Clarke 2005).
With funding from the NSW Environmental Trust, the Dalgety Progress Association undertook a project to rehabilitate and revegetate council land on the bank of the Snowy River outside Dalgety. Drought conditions following planting unfortunately resulted in a high mortality of plantings (Clarke 2005).
The Murrumbidgee CMA undertook willow control, riparian fencing and revegetation works along the Murrumbidgee River in the Dry Plain area as part of the 'Profitable Farmers, Sustainable Systems, Healthy Landscapes' project.
|Project area||Purpose||Source of grant#|
|Lake Eucumbene west of Old Adaminaby||Removal of English Broom on lake foreshores||Natural Heritage Trust, Envirofund, 2002–04|
|Rainbow Beach||Restoration||Natural Heritage Trust, 2000–01|
|Snowy River||Riparian management||Natural Heritage Trust, 2000–02|
NSW Environmental Trust, 2002–03
|Upper Murrumbidgee||Streamside revegetation||Natural Heritage Trust, 2000–01|
|Snowy River||Rehabilitation of creek crossings post fire||Natural Heritage Trust, Envirofund, 2002–03|
|Thredbo River||Rehabilitation of creek crossings post fire||Natural Heritage Trust, Envirofund, 2002–03|
|Rocky Plains||Rehabilitation of creek crossings post fire||Natural Heritage Trust, Envirofund, 2002–03|
|Minnehaha Point, Lake Jindabyne||Rehabilitation||Natural Heritage Trust, 2001–02|
|Upper Snowy River||Riparian demonstration sites||Natural Heritage Trust, 2001–02|
|Upper Snowy River||Willow control||NSW Environmental Trust, 2002–03|
|Murrumbidgee River in the Dry Plain area||Revegetation, willow control and revegetation||Natural Heritage Trust, 2002–03|
|Snowy River in the Dalgety area||Rehabilitation and revegetation||NSW Environmental Trust, 2003-2004 and ongoing|
* More information about these projects can be found on the NHT website and the Environmental Trust website; # Council, community groups or other organisations may have contributed additional funding.
Other nationally funded activities undertaken during the reporting period in the Southern Rivers and Murrumbidgee Catchment Management Authority areas (DIPNR 2004) may also have enhanced riparian condition in the shire.
About the data
Data provided by Snowy River Shire Council.
Clarke, J (2005) Vegetation Officer (Technical), Snowy River Shire Council, personal communication.
DEC—see Department of Environment and Conservation (NSW)
Department of Environment and Conservation (NSW) (2005a) NSW Scientific Committee—Final Determination, Alteration to the Natural Flow Regimes of Rivers, Streams, Floodplains and Wetlands—Key Threatening Process Declaration, NSW Department of Environment and Conservation, viewed 2 August 2005, http://www.nationalparks.nsw.gov.au/npws.nsf/Content/Alteration+to+the+natural+ flow+regimes+of+rivers%2C+streams%2C+floodplains+and+wetlands+key+ threatening+process+declaration.
Department of Environment and Conservation (NSW) (2005b) NSW Scientific Committee—Final Determination, Clearing of Native Vegetation—Key Threatening Process Declaration, NSW Department of Environment and Conservation, viewed 2 August 2005, http://www.nationalparks.nsw.gov.au/npws.nsf/Content/Clearing+of+native+vegetation +key+threatening+process+declaration.
Department of Infrastructure, Planning and Natural Resources (NSW) (2004) 2003/04 Combined NSW Catchment Management Authorities Annual Report, Volume 1: CMA Activities and Achievements, Department of Infrastructure, Planning and Natural Resources, Sydney.
Department of Primary Industries (2005a) Fisheries Scientific Committee Recommendation—Degradation of Native Riparian Vegetation Along New South Wales Watercourses, NSW Department of Primary Industries, viewed 11 August 2005, http://www.fisheries.nsw.gov.au/__data/assets/pdf_file/5287/FR19_rip_veg2.pdf.
Department of Primary Industries (2005b) Fisheries Scientific Committee Recommendation—Installation and Operation of Instream Structures and Other Mechanisms that Alter Natural Flow Regimes of Rivers and Streams, NSW Department of Primary Industries, viewed 11 August 2005, http://www.fisheries.nsw.gov.au/__data/assets/pdf_file/5284/FR21_dams.pdf.
Department of Primary Industries (2005c) Fisheries Scientific Committee Recommendation—Removal of Large Woody Debris, NSW Department of Primary Industries, viewed 11 August 2005, http://www.fisheries.nsw.gov.au/__data/assets/pdf_file/5263/FR18_snags_web.pdf.
DIPNR—see Department of Infrastructure, Planning and Natural Resources (NSW)
DPI—see Department of Primary Industries
OCE—see Office of the Commissioner for the Environment.
Office of the Commissioner for the Environment (2000) Australian Capital Region State of the Environment Report 2000, Office of the Commissioner for the Environment, Canberra (see Snowy River—Riparian Vegetation, Channel Modification and Streambank Disturbance indicators).