CONDAMINE–BALONNE REGION from the Guide to the Proposed Basin Plan
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Wavy marshwort in the Narran Lakes, New South Wales Summary of CONDAMINE–BALONNE REGION From the Guide to the proposed Basin Plan This publication summarises proposals outlined in the Guide to the proposed Basin Plan as they relate to the Condamine–Balonne region. THE region The Condamine-Balonne region lies mainly in southern Queensland and extends about 100km south-west of the New South Wales border. The major waterways in the region are the Condamine, Balonne and Maranoa rivers. Toowoomba is the largest city in the region. Warwick and Dalby are the next two largest urban centres. The region is currently experiencing a population shift from rural to urban areas, which is likely to increase the demand for water in urban areas. Water USE and enVironmental HealtH In the Condamine-Balonne region, there are a number of factors indicating moderate ecological The Authority has compiled the current limits for condition. For example: Native vegetation cover and all forms of water extraction in the Murray-Darling stream condition scores are poor. Fish communities Basin. For surface water these current diversion are moderately diverse with poor habitat quality. limits include watercourse diversions for town and Hydrological conditions in the region were community water supplies, irrigation and industries, ranked as moderate to good, and characterised floodplain harvesting, and interception activities by reduced high flows, reduced annual volumes such as farm dams and forestry plantations. For and minor changes in variability and seasonality. groundwater they include all water diverted from the Macroinvertebrate communities are considered to aquifers of the area. Current diversions are limited be in poor condition across the entire region. Water by existing transitional and interim water resource quality has been deteriorating in lowland areas, plans where these are in place. These are existing with high turbidity, pesticide levels and phosphorus plans, prepared by Basin states, and recognised levels, contributing to algal blooms. Groundwater under the Water Act 2007 (Cwlth) (the Act). Where records show high levels of nitrates. Coal seam gas there are no existing plans, or plans do not apply extraction is emerging as an issue that is likely to to certain types of water extraction, the current impact on water quality. diversion limit reflects the current level of use. The surface water long-term average current ASSESSing enVironmental Water needS diversion limit for the Basin as a whole has been estimated at around 13,700 GL/y and at 1,002 GL/y Many of the environmental assets and functions for the Condamine-Balonne region. The Basin wide of the Murray-Darling Basin have been degraded groundwater long-term average current diversion by the over-extraction of water from the Basin’s limit is 1,786 GL/y. rivers. The Act and Basin Plan seek to address the over-extraction of water to restore and maintain Condamine-Balonne Region the Basin’s key environmental assets and key surface water Current Diversion Limit (GL/y) ecosystem functions. Interceptions Watercourse Diversions Total To determine sustainable diversion limit (SDL) 290 712 1002 proposals it is necessary to work out how much The construction of public storages in the upper water is needed to sustain the health of the Basin’s Condamine and the Balonne River near St George river systems, wetlands and floodplains. To do has resulted in a degree of regulation of these rivers. this, the Authority has undertaken an assessment There is also significant water harvesting into on- of the environmental water requirements of key farm storages for irrigation in this region. environmental assets and key ecosystem functions across the Murray-Darling Basin. In the most part, the assets assessed are large flood-dependent wetland and floodplain systems that support populations of waterbirds and fish, and large forests and woodlands. The assessment of key ecosystem functions gave particular attention to the environmental water requirements of rivers, and system wide processes such as connectivity between rivers and floodplains. Together, these assessments included specific analysis of flows at 106 hydrologic indicator sites across the Basin (88 sites to assess the water needs for the Basin’s key ecosystem functions and 18 to assess the water needs for key environmental assets), as well as analysis of end of system flows in Farmer with organic soya beans near Toowoomba, Queensland each region. The environmental water requirements at a Basin The SDL proposals would require a reduction in the scale have been estimated between 22,100 GL/y current long-term average surface water diversion and 26,700 GL/y (an increase between 3,000GL/y to limit at the Basin scale from 13,700 GL per year to 7,600GL/y from the 19,100 GL/y currently available between 10,700 GL and 9,700 GL per year (reduction for the environment). between 3,000 GL and 4,000 GL per year or 22% to 29%). In the Condamine-Balonne region, 294 key environmental assets have been identified. Of For the Condamine-Balonne region this would the 106 hydrological indicator sites across the equate to reduction in the current long-term average Basin the Condamine-Balonne region contains surface water diversion limit from 1,002 GL/y to five hydrological indicator sites for key ecosystem between 797 GL and 728 GL per year (reduction functions and two hydrologic indicator sites for key between 205 GL and 275 GL per year or 20% to 27%). environmental assets. These are listed below: The SDL proposals would also require a reduction • Lower Balonne River Floodplain System in the current long-term average groundwater diversion limit at the Basin scale by an aggregate • Narran Lakes 186 GL or an average reduction of 10% across the The environmental water requirements for the Basin. The reductions in current diversion limits Condamine-Balonne region have been estimated are required in only 11 of the 78 groundwater SDL between 995 GL/y and 1,312 GL/y (an increase areas. No reductions are proposed for the remaining between 203 GL/y and 520 GL/y from the 792 GL/y 67 groundwater SDL areas where the current currently available for the environment) diversions are assessed as sustainable. Further information on assessing the environmental SDL proposals for the surface water and water requirements of the Basin is available groundwater SDL areas of the Condamine-Balonne at http://www.mdba.gov.au/basin plan/water- region are set out on page 5. assessment-report. SUPPorting commUnitieS SUStainable diVerSion limit ProPOSalS at The Murray–Darling Basin Authority acknowledges THE BASin and regional Scale that implementing SDLs may have significant social The Authority is required to establish new long-term and economic implications for individual entitlement average SDLs for surface water and groundwater. holders and communities across the Basin. SDLs represent the long-term average amount of However, the Australian Government has committed water which can be used for consumptive purposes to recovering sufficient water access entitlements after meeting the environmental water needs that to fully offset the impact of SDLs across the Basin, have been identified. including the Condamine-Balonne region. This will In the Guide, the Authority presents the SDLs as be achieved through a combination of purchasing a range of scenarios for discussion at this stage, entitlements in the market and investments in more rather than choosing a particular value in this efficient irrigation infrastructure. range. This range takes into account all the available Consequently, should these targets be met, there evidence, the quality of that evidence, and the are likely to be no reductions in individual water inherent uncertainty of modelling. entitlement holder allocations. The Authority has determined that 3% of the For further information about these activities go to current diversion limit (around 410 GL/y for the www.environment.gov.au. Basin as a whole and around 30 GL/y for the Condamine-Balonne region) is an appropriate allowance to account for the effect of climate change on surface water SDL proposals. The SDL proposals for groundwater do not include a climate change component. Warrego er Riv Condamine−Balonne o M Condamine−Balonne eg rr a a r a W n o Moonie a Charleville R i v Roma e r k e River e ne r i am Paroo C d on BRISBANE a l C Toowoomba a l r l iver e a nie R r v g o ive i Cunnamulla St George Mo ir R n e R W u o o M QLD r ver iver Goondiwindi a i R R on P oa w lg ar u B C er r Se SA iv e ver Barwon−Darlining R iv Moree G n R ie R w ive rr n yd r i a ir B rr R NSW a iv N e Bourke r Border RiRivers Nam o i C Narrabri R a iv Lower Darling r s e C e t r iv M l Gwydirir e o R g a r x e Tamworth lin c s r B q a a u g C o a h r D g r e a i R e e n i R v k Murray e R i Broken Hill v r i e er v r r Riv e Talbraga r Namoii Dubbo Ivanhoe chlan River La Orange Macquarie−Castlereagh Forbes B Cowra la SYDNEY n River d Mur Mildura ray Griffith C r e Renmark urrumbidge e M e R k ive ADELAIDE r Lachlalan B illabo Murray Bridge ng C Wagga Wagga CANBERRA Pinnaroo reek R Swan Hill ive r M Deniliquin ACT ur r r r a e y Albury e v i v Echuca K R O i Murrumbidgee W Ri ve e n w i n m a s m o a e c R d Shepparton Bendigo i r o v Horsham a R d e R v r i o Eastern Mt Lofty Ranges i v Eastern Mt Lofty Ranges ve A L r Gou e Seymour lbur r n River VIC Ovens Murray Loddon MELBOURNE Wimmera−Avoca Goulburn−Broken Campaspe Condamine−Balonne region Basin Plan regions capital city main town main rivers state border 0 100200 km SUSTAINABLE DIVERSION LIMIT PROPOSALS CONDAMINE–BALONNE REGION SURFACE WATER GROUNDWATER There are two surface water SDL areas There are ten groundwater SDL areas 6a) St George Alluvium: in the Condamine-Balonne region.