Note: Where available, the PDF/Word icon below is provided to view the complete and fully formatted document
Murray-Darling Basin water issues

Download PDFDownload PDF

Parliamentary library briefing book: Key Issues for the 43rd Parliament Page | 58 Page | 59 environment and energy

over the years there has been an over-allocation of water entitlements in many areas of the m urray Darling b asin ( mDb). Water resources have not been able to meet the water needed for environmental flows and human requirements. t o address the problem the m urray-Darling b asin ministerial Council introduced a permanent Cap, starting on 1 July 1997. t he Cap is a limit imposed on the volume of water which could be diverted from the rivers for other uses such as dams or irrigation.

in 2007 the Commonwealth intervened to address over-allocation and established the m urray-Darling b asin a uthority ( mDba). the mDba was to develop and implement a b asin Plan to include s ustainable Diversion l imits ( sDls). on 1 september 2010 the m Dba announced that it would be publicly releasing the Guide to the Proposed Basin Plan on 8 o ctober 2010. l ater it will release the Proposed b asin Plan and the b asin Plan. C siro has advised the m Dba about future climate scenarios for use in modeling future water yield from catchments for the b asin Plan. a 2008 amendment to the Commonwealth Water Act 2007 provided a commitment for critical human needs.

the drought from 2001 through 2009 has severely reduced the water resources of the m Db. the years 2006-07, 2007-08 and 2008-09 had

the first, third and seventh lowest inflows to the m urray r iver on record. t he low flows plus continued water use, albeit at reduced levels, resulted in the l ower l akes dropping to record low levels, exposing acid sulphate soils to the air and increasing salinity levels six-fold. t he drought resulted in a decrease in both area of irrigation and volume of water used.

the basin Plan

the basin Plan, due to begin in 2011, must contain:

long-term average s Dls for the amount of • surface water and groundwater that can be taken from b asin water resources requirements that state W rPs must comply •

with an environmental watering plan for the b asin • a water quality and salinity management plan • for the b asin and

rules about trading of water. •

these will operate together to ensure that the social, economic and environmental outcomes of the water resources are not compromised. t he Plan will also include an outline of risks to b asin

water resources, such as climate change, along with strategies to manage those risks.

the sDls will be implemented through the water resource plans, which will be developed by the states but accredited by the Commonwealth. however there will be a five-year phase-in period for the s Dls for each W rP.

the Wentworth g roup, in a June 2010 paper, argued that the m Db should not have its flow regime reduced below two-thirds of its natural level. t o ensure that flow rates stay about this, reductions in s Dls would be required across the basin. While the s Dls could remain at more than 90 per cent of present diversion levels for most

Murray-Darling Basin water issues bill m cCormick, s cience, t echnology, e nvironment and r esources s ection

the murray Darling b asin a uthority

the mDba is responsible for planning the integrated management of the water resources of the m Db. the mDba will prepare the b asin

Plan for adoption by the Commonwealth minister for Water and will implement and enforce the Plan—this will set a new cap on water use in the basin. t he mDba also advises the m inister on the accreditation of state water resource plans (WrP).

catchments, cuts to diversions in the m urray and murrumbidgee rivers would have to be 39 per cent and 65 per cent respectively.

such potentially large reductions in allocations have been of great concern for irrigation and farming groups. e arly this year the n ational farmers f ederation said that, for agriculture, the basin Plan was a ‘train smash waiting to happen’.

reduction in water diversions

in the present W rPs, the reduction in water allocations that are necessary to meet the new sDls will be achieved by the Commonwealth purchasing water entitlements on the water market, and through improving water use efficiency. two programs aim to achieve this:

the $31 billion r estoring the b alance in the • murray-Darling b asin program to purchase entitlements for use as environmental water and the $5.8 billion s ustainable r ural Water u se •

and infrastructure program.

the alP gave a 2010 election commitment that it would buy as much water as necessary from willing sellers to restore the m urray r iver to health as needed under the b asin Plan.

mining and water

farmers in parts of the m Db have raised the issue of the impact of coal mining and coal seam methane extraction on the quantity and quality of the groundwater resources. s ection 255 a of the Water Act 2007 requires independent studies of the impacts of subsidence mining on the groundwater systems in the b asin before any mining licences are granted. Concerns remain about the impacts of coal seam methane production.

snowy r iver flows

the snowy m ountains s cheme diverted water to the m Db and this reduced the flow of the snowy r iver above the m owamba r iver to just one per cent of its normal long-term average. i n order to reduce the environmental impacts on the s nowy from this diversion, in 2002 ns W, Victoria and the Commonwealth agreed to fund a scheme to return 21 per cent (212 gigalitres) of the s nowy’s original flows by 2012. t he recent drought has resulted in a slower release of environmental water than expected. During the 2010 election campaign the al P announced that it had reached an agreement with the ns W and Victorian g overnments. t his agreement promised a $13.7 million compensation payment to s nowy hydro for the 56 gigalitres in water to be released from the Jindabyne Dam into the s nowy r iver over the next two years.

library publications and key documents

murray Darling b asin a uthority ( mDba), Issues paper: development of sustainable diversion limits for the Murray-Darling Basin, mDba, Canberra, 2009, f

a martyn, J t omaras and b m cCormick, Water Amendment Bill 2008 , bills digest, no. 45, 2008-09, Parliamentary l ibrary, Canberra, 2008, f

fhs Chiew, W Cai and in smith, Advice on defining climate scenarios for use in the Murray-Darling Basin Plan modelling, Csiro report prepared for the m urray-Darling b asin a uthority, Canberra, 2009, http://www.mdba. siro.pdf

Wentworth g roup of Concerned s cientists (W gCs) rQ grafton, i k owalick, C miller, t s tubbs, f Verity and k Walker, Sustainable diversions in the Murray-Darling Basin: an analysis of the options for achieving a sustainable diversion limit in the Murray-Darling Basin, Wentworth g roup, s ydney, 2010.