BRS Seminar Program

1. BRS Seminar Program Science & Conflicts over Water in the Lower Balonne Peter Cullen Visiting Fellow, BRS

2. N Condamine-Balonne Basin MARANOA RIVER CONDAMINE RIVER ST.GEORGE BALONNE R. LOWER BALONNE FLOODPLAIN CULGOA R. BALONNE MINOR R. BRIARIE CK DIRRANBANDI BALLANDOOL R. NARRAN R. QLD HEBEL NSW BOKHARA R. 0 20KM

3. Flow thresholds Flow ML/D Av Return Ecol Sig 25,000 ~ 1.6 years Water moves out of main channel 45,000~ 3 years3 vegetation types 50 % wet 60,000~ 3.6 yearsMain flow paths full 70,000~ 4 yearsAt least 40 % of floodplain wet. 120,000~ 8 years70 % of floodplain wet

4. Harvesting of Floodflow Water • Bunds to divert floodflow • Pump from river & distributary channels • Large, shallow on farm storages • Irrigated cotton • Major economic benefits

5. Pressures • Huge wealth from cotton • Seen as most over developed part of MDB • Degradation of river health • Salinity risks • Inadequate payments for water • Pressures on Qld re cap on MDB • Threat to NCC payments • History of court action

6. The issues • View that water in LB is over-committed • LB river system degraded • Anger that irrigators don’t pay much for water • What should be done? • All science contestable - Smartrivers

7. The Cubbie Option • Proposed 53% of MAF to environment rather than 47% as present • Premier Beattie proposed acquisition of largest cotton property • Local outrage - no action needed, & if needed any pain should be spread! • Beattie proposed independent scientific review

8. Terms of reference • Review DNRM IQQM for LB. • Review ecological condition of the LB, including floodplains & wetlands. • Propose an ecological definition of healthy working river. • Review likely future ecological conditions in LB • Review reversibility of likely impacts • Advise on monitoring

9. Review process • Cullen, Mein & Marchant • Advertised & invited call for submissions • Community Reference Group established (Boully as chair) • Held series of hearings where submissions put & questions asked

10. The water conflicts • interests - large financial benefits to growers & community • values - wetland & river health issues • data - is the river degraded & what should be done • structural - DNRM, MDBC, NCC & irrigators in conflict • labelling - greenies, rapers etc

11. The data conflicts- Irrigators • flow measurement underestimates flood flows • probably already at 53% • IQQM modelling unreliable • river not degraded at all • Irrigators wanted to be clear as to the environmental assets & what they needed

12. The Flow Findings • IQQM modelling & flow measurement adequate for purposes • Workshops with irrigators reduced concerns about IQQM • Emphasis on MAF a diversion - focussed on stream gauging errors • Don’t expect better than +/- 30% in floods

13. Mean Annual Flow ? • We know the lowest flow is zero • We don’t know max flow - only 80 yrs records ( need 250 yrs to be 90% sure) • MAF a nonsense - not a useful management concept in such systems

14. The Ecological Assets • Rivers & distributary channels • Coolabah floodplain National Parks • Narran lakes • Darling river

15. The challenge of ecological assessment • LB not yet seen the impacts of current infrastructure - built in last couple of years • Lag times for ecological impacts to be obvious - 70 yrs for some wetlands and they are still changing

16. Rivers & distributary channels • good woody debris • riparian improved with move from grazing • weirs block fish in low flow but not floods • pulses of flow • all storage’s are off-river

17. Rivers & distributary channels Invertebrate data • Initial TAP reported degradation • Subsequent work did not support • no real downstream trends • similar to adjacent undeveloped catchments

18. Rivers & distributary channels Fish data • no significant downstream trends • if a subtle trend, problem of causality - flow or distributary system • similar fish to adjacent undeveloped catchments

19. Rivers & distributary channels • currently in reasonably healthy state with regard to invertebrates and fish • delighted irrigators and did not please Govt • based on reasonable sampling • are these good indicators in ephemeral systems?

20. Coolabah floodplain National Parks • limited information submitted • responsible agencies seem to manage in data free way • Irrigators hardly influence the big flood - every 10 yrs • Expect Coolabah to cope, but red gums may go • Reduction in downstream pastoral production

21. Darling river • Upper Darling degraded - several studies • LB may contribute about 20% of flow • No submissions from NSW or MDBC on this • LB contributes about 1% of flow at Murray mouth

22. Narran lakes • Ramsar wetland and important bird breeding area • Used to flood every 2 yrs on average • Irrigation development will let it flood every 7 yrs • Currently in good condition but strong view they would not survive likely wetting regime

23. Narran lakes • major study by CRC for Freshwater Ecology just starting • Interim wetting to be every 3.5 yrs • Irrigators to work with Dept modellers and find least impact way of delivering this • A share of medium floods • No impact on small floods

24. Community Reference Group • Irrigators, business, grazing and green groups • listened to major presentations • allowed to ask questions • most hearings allowed wider public to attend • had to report to Govt on our process

25. Community Reference Group • helped focus on important issues • a great learning experience as they observed our cross-examination of science submissions • saw themselves as vehicles for a variety of viewpoints rather than presenting a unified community view

26. Agency science • Boxes of reports • Consultant after consultant • Series of trivial, short studies rather than a serious effort • Little integration of knowledge • Little discrimination as to what we needed to do our job

27. Agency science • Must not protect from normal quality assurance procedures of publishing • If time tight, need independent peer review • Management domination of science? • Timeliness of science - setting strategic work priorities

28. Science findings • science is always contestable • Irrigators hired their own scientists and with regard to river health successfully contested agency findings • agency should never have got into this position