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Lachlan catchment

Planning for 2014-15

Commonwealth environmental water use options 2014-15: Lachlan River Valley identifies potential Commonwealth environmental watering actions for 2014-15. Decisions on using Commonwealth environmental water will be made throughout the year based on seasonal, operational and management considerations. If you wish to provide suggestions for Commonwealth environmental water use please contact us at or send us your suggestion by visiting: Your suggestions for potential water use options.

Environmental watering in the catchment in 2014-15

Watering action Status of Commonwealth action
Lachlan River system, including floodplain In progress
Lower Lachlan Swamps Not yet commenced
Lower Lachlan System bird breeding contingency Not yet commenced

A summary of Commonwealth environmental watering from previous years in the Lachlan is included below. For further information about Commonwealth environmental watering in the Lachlan and the outcomes achieved, please refer to the Commonwealth environmental water Outcomes Reports and Annual Reports.

Water availability and portfolio management

For more information regarding the characteristics of entitlements and the water resource plan held in the Lachlan catchment please refer to New South Wales Department of Primary Industries Office of Water

Water trading

Information on future trade considerations is available at: Portfolio Management Update

Information on current trading actions is available at: Current Trading Actions

Information on previous trading actions is available at: Trading Outcomes

Environmental watering in the catchment in previous years

Environmental watering in the catchment in 2013-14
Watering action Amount of water delivered (ML) Status of action
Lachlan River system, including floodplain 23 017 Completed
Total in 2013-14 23 017  
Environmental watering in the catchment in 2012-13
Watering action Amount of water delivered (ML) Status of action
Booligal Wetlands 223 Suspended
Lachlan River system, including floodplain 50 837 Completed
Total in 2012-13 51 060  
Environmental watering in the catchment in 2011-12
Watering action Amount of water delivered (ML) Status of action
Merrimajeel Creek 5 006 Completed
Muggabah Creek 3 585 Completed
Merrowie Creek (Tarwong Lakes) 11 568 Completed
Total in 2011-12 20 159  
Environmental watering in the catchment in 2010-11
Watering action Amount of water delivered (ML) Status of action
Merrimajeel Creek - Booligal Swamp 1 573 Completed
Merrowie Creek - Tarwong Lakes 2 145 Completed
Merrowie Creek 3 051 Completed
Merrimajeel Creek - Murrumbidgil Swamp 252 Completed
Total in 2010-11 7 021  

Catchment profile

Where is it?

The Lachlan Valley catchment in central western NSW centres on the Lachlan River. It is bounded to the east by the Great Dividing Range, to the north by the Macquarie, to the south by the Murrumbidgee and the north-west by the Darling catchment. Rising near Gunning in the east, the Lachlan River travels around 1,400 km. The diverse landscape influences the vegetation, which ranges from temperate forests, woodlands and grasslands in the east to semi-arid woodlands, mallee and shrublands in the west.

The catchment area is 86,554km2, or 8.3 per cent of the total MDB area. It is essentially a terminal system with the Lachlan River ending in the extensive wetlands of the Great Cumbung Swamp. The Lachlan River itself is only intermittently connected to the Murrumbidgee River when both rivers are in flood. Tributaries to the Lachlan include Belubula, Boorowa and Crookwell Rivers. The Lachlan catchment is regulated by the two major water storages of Wyangala Dam (capacity 1,220 GL) and Carcoar Dam (capacity around 36 GL), and other regulating weirs such as Booberoi and Lake Brewster.

Northern Catchments page


red irregular shaped area  denotes ramsar site
Ramsar site

yellow irregular shaped area denotes diwa site
DIWA site

Lachlan Catchment

What makes this place so special?

Booligal Wetlands shortly after period when
Commonwealth environmental water was used
(November 2010).

Photo: Paul Packard © NSW Department of
Environment and Climate Change

The Lachlan catchment is an ecologically significant area because it includes:

  • wetlands in the lower western region covering 471,011 ha, 95 per cent of which are on the floodplain
  • nine areas listed on the Directory of Important Wetlands in Australia (DIWA) with particular value as waterbird and migratory bird habitat
  • native fish species including the Australian smelt , freshwater catfish , silver perch , golden perch , big-headed gudgeon and western carp gudgeon
  • habitat for threatened species, such as Sloane's froglet, Australian painted snipe, osprey, blue-billed duck and the fishing bat
  • areas of river red gum forest and woodland, black box woodland and lignum.

The nine nationally important wetlands in the Lachlan catchment are: Booligal Wetlands, Murrumbidgil Swamp/ Lake Merrimajeel, Cuba Dam, Merrowie Creek (Cuba Dam to Chillichil Swamp), Great Cumbung Swamp, Lachlan Swamp, Lake Brewster, Lower Mirrool Creek Floodplain, and Lake Cowal/Wilbertroy Wetlands. The Booligal Wetlands and the Great Cumbung Swamp are notable sites as both wetlands are well known for providing habitat for both large numbers and species of waterbirds, particularly straw-necked, white and glossy ibis, when the area is flooded. The catchment has been recorded to support 80,000 breeding pairs of ibis. The Great Cumbung Swamp also contains one of the largest stands of river red gums in NSW.

What does the latest science say about the ecological health of the catchment?

The Sustainable Rivers Audit (SRA), coordinated by the Murray-Darling Basin Authority, provides scientifically robust assessments of the ecological health of the Basin's river valleys. The overall ecosystem health of the Lachlan Valley catchment as reported by the SRA is summarised below.

SRA Report Overall ecosystem health of catchment
SRA 1 (based on data collected from 2004 to 2007) Poor
SRA 2 (based on data collected from 2008 to 2010) Very poor

The CSIRO Sustainable Yields report on the Lachlan Valley Catchment indicated that the current level of surface water extraction in the Lachlan River (Lachlan Valley Catchment) is moderately high, with 28 per cent of average available water being diverted for use. Under the best estimate 2030 climate conditions there would be a decrease of 11 per cent in water availability.

Note that the boundaries of this catchment as defined by the Sustainable Rivers Audit and the Sustainable Yields report differ slightly to the boundaries used here.

Environmental water delivery references

Environmental water delivery: Lachlan River collates current knowledge of the operational and administrative arrangements for the delivery of environmental water to the Lachlan River. The document provides an overview of the environmental assets and potential environmental water use options. This work has been undertaken to support the efficient and effective use of environmental water and to engage communities on how this may best be achieved. This aims to encourage community discussion and feedback on the use of environmental water, to identify future opportunities and recognise operational risks and constraints. Comments on the document are encouraged and can be provided to: