Water resources and management overview ... - NSW Office of Water

Water resources and management overview

Border Rivers Catchment

www.water.nsw.gov.au

Publisher NSW Department of Primary Industries, Office of Water. Level 18, 227 Elizabeth Street GPO Box 3889 Sydney NSW 2001 T 02 8281 7777 F 02 8281 7799 [email protected] www.water.nsw.gov.au

The NSW Office of Water manages the policy and regulatory frameworks for the state’s surface water and groundwater resources, to provide a secure and sustainable water supply for all users. It also supports water utilities in the provision of water and sewerage services throughout New South Wales. Water resource and management overview: Border Rivers Catchment April 2012 ISBN 978 0 7313 3509 1

This report may be cited as: Green D., Ali A., Petrovic J., Burrell M., Moss P. (2012) Water resource and management overview: Border Rivers Catchment, NSW Department of Primary Industries, Sydney Cover photo: Boobera Lagoon (courtesy MDBA, Arthur Mostead)

© State of New South Wales through the NSW Department of Trade and Investment, Regional Infrastructure and Services, 2012 This material may be reproduced in whole or in part for educational and non-commercial use, providing the meaning is unchanged and its source, publisher and authorship are clearly and correctly acknowledged. Disclaimer: While every reasonable effort has been made to ensure that this document is correct at the time of publication, the State of New South Wales, its agents and employees, disclaim any and all liability to any person in respect of anything or the consequences of anything done or omitted to be done in reliance upon the whole or any part of this document.

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Water resources and management overview - Borders River catchment

Contents 1

The Border Rivers catchment ....................................................................................................... 1

2

Climate .......................................................................................................................................... 3 2.1

Rainfall ................................................................................................................................ 3

2.2

Evaporation ......................................................................................................................... 4

3

Land use........................................................................................................................................ 5

4

Environment .................................................................................................................................. 7

5

4.1

Native vegetation ................................................................................................................ 7

4.2

Parks and reserves ............................................................................................................. 7

4.3

Wetlands ............................................................................................................................. 8

4.4

Significant biodiversity ........................................................................................................ 9

Surface water .............................................................................................................................. 10 5.1

Dumaresq River ................................................................................................................ 10

5.2

Severn River ..................................................................................................................... 10

5.3

Macintyre River ................................................................................................................. 10

5.4

Weir River ......................................................................................................................... 11

5.5

Barwon River..................................................................................................................... 11

5.6

Streamflow characteristics ................................................................................................ 11

6

Groundwater................................................................................................................................ 15

7

River operations and management ............................................................................................. 16 7.1

Border Rivers Commission ............................................................................................... 16

7.2

Border Rivers Intergovernmental Agreement ................................................................... 16

7.3

Major storages and regulating structures ......................................................................... 16

7.4

Licensed water use ........................................................................................................... 18 Surface water .................................................................................................................... 18 Groundwater ..................................................................................................................... 20

7.5

Water sharing plans .......................................................................................................... 21 Surface water sharing plans ............................................................................................. 21 Groundwater sharing plans in the NSW Border Rivers .................................................... 22 Plans in preparation .......................................................................................................... 24

8

References .................................................................................................................................. 25

i | NSW Department of Primary Industries, NSW Office of Water, April 2012


Tables Table 1: Land use types in the Border Rivers catchment ..................................................................... 5 Table 2: Threatened aquatic species of the Border Rivers catchment ................................................. 9 Table 3: Mean daily flow for selected Border Rivers gauges .............................................................. 11 Table 4: Major water storages in the Border Rivers catchment .......................................................... 17 Table 5: Surface water share components in the Border Rivers catchment as at 30 June 2011................................................................................................................................... 19 Table 6: Groundwater entitlements in the Border Rivers catchment as of December 2011............... 20

Figures Figure 1: The Border Rivers catchment ................................................................................................ 1 Figure 2: Topography and elevation in the NSW Border Rivers catchment ......................................... 2 Figure 3: Average annual rainfall in the NSW Border Rivers catchment .............................................. 3 Figure 4: Average monthly rainfall at Inverell 1949-2010...................................................................... 4 Figure 5: Average daily evaporation at Inverell 1965-2010................................................................... 4 Figure 6: Land use in the NSW Border Rivers catchment .................................................................... 6 Figure 7: Annual flow in the Macintyre River at Wallangra 1937-2011 ............................................... 12 Figure 8: Daily flows and cumulative deviation from the mean for Macintyre River at Wallangra........................................................................................................................... 14 Figure 9: Groundwater Management Areas in the Border Rivers catchment ..................................... 15

ii | NSW Department of Primary Industries, NSW Office of Water, April 2012


1 The Border Rivers catchment The Border Rivers comprise the catchments of the Dumaresq, Severn, Macintyre and Barwon Rivers which drain from the Great Dividing Range between Inverell in far northern New South Wales (NSW) and Warrenbayne in Southern Queensland (Figure 1). The catchment occupies an area of approximately 49,500 km2 of which approximately 24,500 km2 is situated within NSW. The Dumaresq River, Macintyre River and part of the Barwon River downstream of the Weir River form the border between NSW and Queensland for approximately 470 km. ( The Border Rivers are regulated by three dams – Glenlyon Dam on Pikes Creek (QLD), Coolmunda Dam on Macintyre Brook (QLD), and Pindari Dam on the Severn River (NSW). The main tributaries draining from Queensland are Pikes Creek and Macintyre Brook which enter the Dumaresq River, and the Weir River which enters the Macintyre River. The lower end of the catchment is characterised by a complex series of anabranching channels. The junction of the Weir and Macintyre Rivers marks the start of the Barwon River, and the town of Mungundi on the Barwon River marks the downstream end of the Border Rivers catchment. The Border Rivers flows through lands previously occupied by the Kamilaroi and Bigambul Aboriginal people. The catchment supports a population of around 50,000 people. In NSW the population is concentrated in the major centres of Glen Innes, Inverell, and Tenterfield which support around 30,000 people between the three local government areas. The largest towns in the Queensland part of the catchment are Goondiwindi and Stanthorpe which both have populations of around 5,000 people. The main agricultural use of land is for grazing and dryland cropping, and this covers around ninety per cent of the catchment. Irrigation for the production of cotton occurs on the western plains between Goondiwindi and Mungindi. Figure 1: The Border Rivers catchment

1 | NSW Department of Primary Industries, NSW Office of Water, April 2012


The eastern half of the Border Rivers comprises the ranges and foothills of the Great Dividing Range with elevations from 1,500 metres to 500 metres in the lower foothills (Figure 2). The south western region of the catchment comprises flat alluvial plains which are drained by a series of intermittent watercourses, the principal ones being Croppa Creek, Whalan Creek and Gil Gil Creek. The elevation across these plains ranges from around 400 metres in the eastern extent to just 150 metres at Mungindi. Dumaresq River at Glenarbon Weir

Figure 2: Topography and elevation in the NSW Border Rivers catchment



2 Climate 2.1 Rainfall Annual rainfall across the Border Rivers catchment decreases along an east-west gradient from over 1,000 mm in the eastern ranges around the Great Dividing Range to around 500 mm in the west at Mungindi (Figure 3). The rainfall is strongly seasonal with the highest volumes occurring through summer storm activity. Average rainfall significantly increases from October with the summer months all averaging around 100 mm per month (Figure 4). In contrast the average monthly rainfall between April and September is 40–50 mm. Figure 3: Average annual rainfall in the NSW Border Rivers catchment

Source: Bureau of Meteorology



Figure 4: Average monthly rainfall at Inverell 1949-2010

Source: Bureau of Meteorology Climate Data Online

2.2 Evaporation Annual evaporation has a strong east-gradient across the Border Rivers catchment, with average Class A pan evaporation exceeding the average rainfall across the entire catchment. Annual evaporation is around 1,200 mm in the eastern ranges and over 2,000 mm in the far west of the catchment at Mungundi. Mean daily evaporation at Inverell ranges from two mm per day in winter to 6.5 mm in summer (Figure 5: Average daily evaporation at Inverell 1965-2010) Figure 5: Average daily evaporation at Inverell 1965-2010

Source: Bureau of Meteorology Climate Data Online



3 Land use Land use in the Border Rivers catchment is dominated by extensive agriculture with approximately 67 per cent of the catchment used for grazing and 18 per cent used for dryland cropping (Table 1). Grazing occurs right throughout the catchment while dryland cropping occurs predominantly on the central plains south of Goondiwindi and Boggabilla. The principal crops are winter cereals, summer grain and oilseed. Approximately two per cent of land has been developed for irrigation, mostly in the west of the catchment between Goondiwindi and Mungindi. Cotton accounts for around 85 per cent of all irrigated crops, covering around 40,000 hectares of the NSW catchment, and having an economic value of around $150 million per annum (DWE 2009a). Other irrigated crops include fruit, vegetables, wine grapes, lucerne, cereal crops, corn, peanuts, and fodder for feedlots. Conservation and other native vegetation together account for five per cent of land use in the Border Rivers, with most of this being in the eastern ranges. Forestry is predominately in the QLD portion of the catchment with Western Creek State Forest making up the majority of the 7.6 per cent catchment coverage. Table 1: Land use types in the Border Rivers catchment Land use type

Grazing

Area (km2)

Proportion of catchment (%)

32,297

67.2

Dryland Cropping and Horticulture

8,701

18.1

Forestry

3,657

7.6

Native Landscape

1,407

2.9

Irrigation

975

2.0

Conservation

914

1.9

Residential

96