water wednesday - professor barry hart

Life Impact The University of AdelaideSlide 0

Water Research Centre

AWA SA Branch/Adelaide University

“Water Wednesday”

Murray Darling Basin Plan: Striking the

Right Balance

Chair: Justin Brookes


The Environment Institute



AWA SA Branch

Technical Seminar

Seminar sponsors





Prof Barry Hart

Monash University

Murray Darling Basin Plan:

Striking the Right Balance



The MD Basin Plan - Striking the Right Balance

Prof Barry HartMDBA

Why the need?

• Significant changes to hydrology

– Less flooding (overbank flows)

– Changes to seasonal flow regimes

• Overallocation of water resources

– Particularly severe in southern basin

• Degradation of environment

– River red gums dying

– Fish populations reduced

– Waterbird number reduced

– Algal blooms

– Water quality degradation - salinity

– Murray mouth closed

• Increased threat to agricultural production

Hydrology of the Basin

Northern Basin

Southern Basin

Balancing the equation

Murray - 58%, 42%

Darling - 28%, 72%

Environment

(58%)

Consumptive

42%

(Baseline - at 2009)

Basin Plan - purpose

• Objective

– to develop and implement an integrated waterresource Plan for the whole Basin

• Basin Plan seeks to rebalance the system

– more water for the environment, but

– minimise impacts on irrigators and localcommunities

• MDBA’s task

– set the bounds (Sustainable Diversion Limits -SDL) and work with the States and localcommunities to implement

• MDBA only has powers to do part of thereform, but ……

The Basin Plan

The Basin Plan must include:

• Sustainable diversion limits (SDLs) =

Ecologically Sustainable Level of Take

(ESLT)

• Water resource plan accreditation

• Environmental Watering Plan

• Water Quality & Salinity Management

Plan

• Water trading rules

• Monitoring and Evaluation program

What are we aiming to achieve?

A healthy working Basin

• critical drinking water needs can be met

• rivers are connected to creeks, billabongs and

floodplains

• healthy ecosystems supporting a wide variety of

plants and animals

• sufficient flows to flush nutrients and salt through the

system

• sustainable growth in food and fibre production

• long-term confidence for businesses and communities

• ‘fit for purpose’ water quality

• a free market for trading water

What we wish to achieve

Four stage process

2012-2019

Implement

ation

2012

The

Basin

Plan

• adoption

2011

The

propose

d Basin

Plan

• information• formal

submissions

2010

The

Guide

• information• feedback

Review in 2015

Reports

The Task

Decision-making process

Environmentally sustainable level of take (ESLT)

= Sustainable Diversion Limit (SDL)(more than just a volume)

Implications• Social and economic

• Environmental

Environment (Science + Judgements)• Define the MDB environment we want to protect

• Define what we want it to be (objectives)

• Determine how much water needed to achieve this (EWR)

Balancing

Defining the environment

• Largely done in the Water Act

• Key environmental assets

- wetlands, floodplain forests, rivers, estuary (Coorong)

- largely specific areas, locations

- judgements required to define which are ‘key’ assets andhow much water they need

• Key environmental functions

- Largely ecological processes

- primary production, fish migration, triggers for breeding,material transport

- judgements required in relating functions with flows

• Ecosystem services

- Not considered yet

How much water is needed?

Key environmental assets

• Too many to assess all (selected 2000+ KEAs)

• Selected 18 to act as indicators - these are

- hydrologically representative

- have good information base on them

• Most indicator assets are wetlands or floodplainforests (require high flows largely through overbankflows)

• High flows make largest contribution to volume andtherefore largest influence on ESLT

Lower Balonne River

Floodplain SystemGwydir Wetlands

Narran Lakes

Macquarie

MarshesLower Darling

River System

Riverland – Chowilla

Floodplain

Coorong, Lower

Lakes and Murray

Mouth

Hattah Lakes

Wimmera River

Terminal Wetlands

Mid Murrumbidgee Wetlands

Booligal Wetlands

Lachlan Swamps

Great Cumbung Swamp

Lower Murrumbidgee Wetlands

Edward Wakool River System

Gunbower Koondrook Perricoota Forests

Barmah Millewa Forest

Lower Goulburn River Floodplain

Indicator

Assets

How much water is needed?

Barmah-Millewa - Targets & Flows

Delivered under current

operating conditions

Needs trib inflows or

unregulated flows

Not all years

River operations constraints

Only achieved with large

unregulated flows (floods)

Achievement of targets

Environmental water

• Within each catchment

• Two components:

- Local requirements (to water the assets andfunctions in that catchment)

- Downstream requirement (to water assets andfunctions in downstream parts of the river)

• Example - Goulburn

- Local - for river channel and lower GoulburnFloodplain

- Downstream - contribution to River Murray assetsand functions

Reports

Balancing

SDL

Key

ecological

assets

Key

ecological

functions

Hydrological

asset sites

(18)

Ecological

water

requirements

(EWR)

Hydrological

function sites

(88)

Socio-economic

assessment

System

constraints

Social and economic affects

• Long term, Basin scale

– small economic affect

• Short term, local scale

– small communities with high reliance on

irrigation will be most at risk

How much more e-water needed?

Current thinking:

Basin wide - 2,750 GL/y (long-term average)

eWater Recovery:

Indicative rebalancing

Additionalenvironmental

water

2,700 GL/y

8,100 GL/y

5,100 GL/y

16,800 GL/y

33%

67%

North South

25%

75%

44%

56%

Planned vs Held e-water

Strategies to adjust

Irrigators

• Commonwealth buy-backs ($3.1 bill)

• Irrigation modernisation ($5.9 bill)

Communities/businesses• Lost water = $ lost to towns/regions

• Debt levels high due to drought

• Mitigating impacts - gov’t assistance?

GAP

Implementation

• Major rural reform - will take time

• The Basin Plan as part of a Plan for the Basin

• Will need a ‘whole of government’ response to

minimise impacts on local communities

• States and community will be vital part of the

implementation through developing and

implementing regional water resource plans

• Need less focus on the SDLs and more on

how the extra water is used

Opportunities

• Time extension to 2019 provides opportunity

• In 2012 the Basin Plan will recommend

‘indicative SDLs’ for each catchment and the

Basin

• This is within a ‘constrained’ system

• Opportunities to address some of these

constraints (with potential changes to SDLs)

• Opportunity to progress towards more

contemporary river management

Constraints

• Operational constraints

- Change river operating rules (currently focused on

consumptive water delivery)

- Optimise storage management

• Policy constraints

- Modify storage carryover rules

- Water sharing plans - alter to better protect environmental

water during droughts

- Remove state-based policies that impact of environmental

outcomes

• Physical constraints

- Remove/modify infrastructure that impede high flows

- Purchase easements to allow high flows to be delivered

- Adopt engineering works and other innovative solutions

850 GL/y

recovered

1200 GL/y

recovered

Environmental water

Consumptive water

Indicative

SDL

Gap

An adaptive plan• More buybacks

• Address some constraints

• More modeling & science

• Environmental works

Final SDL

10 Key Points

• Vision is for a healthy working basin

• Basin Plan is next step of the journey

• We have a robust starting point

• It’s more than just a volume of water

• Progress will be reviewed in 2015

• Savings from the ‘rules review’ will see SDL adjusted

• Northern basin is different to southern basin

• One size does not fit all - catchments are different

• How water is recovered will affect social & economic

impacts

• Localism is critical

Summary

• Development and implementation of the Murray-

Darling Basin Plan – major rural reform

• Significant reductions in current diversion limits

required

• Commonwealth investment (ca. $9 billion) should

‘purchase’ all the water required

• But still need a ‘whole of government’ response to

minimise impacts on some local communities

• Many opportunities to progress towards more

contemporary river management by addressing many

of the current constraints

• This is a ‘journey’ we have just begun



•

Australian Water Association

Keep in touch and stay informed with water industry professionals

- Events, conferences, courses and study tours

- National and regional interest groups and activities

- Opportunities to connect with senior industry representatives and experts.

- Research and publications – Water Journal and Australian Water Directory, plus

extensive online library of technical papers

SA AWA Branch

More Technical events to be held in April, May and June:

Next event -

Thurs 19 April SA Young Water Professionals Seminar

Topic: Adelaide’s North South Interconnector Pipeline project





AWA SA Branch/Adelaide University

“Water Wednesday”

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