BRS Seminar Program

Science & Conflicts over Water in the Lower

Balonne

Peter Cullen

Visiting Fellow, BRS

0 20KM

QLD

NSW

BALONNE R.

CULGOA R.

NARRAN R.

BOKHARA R.

BRIARIE CK

BALLANDOOL R.

BALONNE MINOR R.

ST.GEORGE

HEBEL

DIRRANBANDI

LOWER BALONNEFLOODPLAIN

CONDAMINE RIVER

N

Condamine-Balonne Basin

MARANOA RIVER

Flow thresholdsFlow ML/D Av Return Ecol Sig

25,000 ~ 1.6 years Water moves out of main channel

45,000 ~ 3 years 3 vegetation types 50 % wet

60,000 ~ 3.6 years Main flow paths full 70,000 ~ 4 years At least 40 % of

floodplain wet.120,000 ~ 8 years 70 % of floodplain

wet

Harvesting of Floodflow Water

• Bunds to divert floodflow• Pump from river & distributary

channels• Large, shallow on farm storages• Irrigated cotton• Major economic benefits

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

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

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

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

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

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

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

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

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

The Ecological Assets

• Rivers & distributary channels• Coolabah floodplain National

Parks• Narran lakes• Darling river

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

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

Rivers & distributary channels

Invertebrate data• Initial TAP reported

degradation• Subsequent work did not

support• no real downstream trends• similar to adjacent

undeveloped catchments

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

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?

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

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

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

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

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

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

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

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

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