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Water use in the Murray Darling Basin. Key Knowledge and Skills . Importance of water as a resource in Australia Distribution of water resources Factors affecting water use Factors affecting the pattern of water use . Europeans influence . - PowerPoint PPT Presentation
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Water use in the Murray Darling Basin
Key Knowledge and Skills
• Importance of water as a resource in Australia
• Distribution of water resources
• Factors affecting water use
• Factors affecting the pattern of water use
Europeans influence
• Europeans settled in some regions of the MDB in the 19th century, at a time when there had been a series of wet years
• Make the desert bloom• Didn’t have long term rainfall records• Ignorant of highly variable climate and river
flows
Land Use
• Sheep and cattle were introduced to the region in large numbers
• Crops requiring large amounts of water were planted
• The country's growing population had to be fed
• Export markets needed to be established
Clearing
• ~15 billion trees were cleared to:• Establish farms• Supply fuel for the paddle steamers which
moved goods from the inland farms to the ports
Irrigation
• The application of water to crops or pasture, especially in dry regions, to supplement rainfall
• Began in the 1880’s in Mildura• Idea from California
Human uses
• Water is required to:– Generate power– Domestic– Industrial– Stock– Forestry– Mining– Recreation– Tourism– Irrigation, and….
Natural uses
• Water also provides a habitat for:– Mammals,– Birds– Reptiles– Frogs and – Freshwater fish.
Some of these species are now endangered
• The Murray river has been described as one of the hardest working rivers in the world, in terms of the amount of water that is taken out of it, and the variety of natural and human needs it supports
Important
• The Basin is Australia’s most important agricultural region
• Producing over 1/3 of the country's food supply
• Providing 39% of the national Income from agricultural production
• There is a strong spatial association between the basins dry land farming regions and the production of beef cattle, sheep and wheat.
There is a strong spatial association between land that is irrigated and the production of dairy products, cotton, rice, fruit and vegetables
Irrigation areas Cotton
Irrigation
• Majority of all water used in Australia is consumed in the MDB (52% in 2009) mainly for irrigation
• Almost 90% of the water is diverted for use• The basin contains:– 65% of Australia’s total irrigated land– 50% of the nations sheep– 25% of its cattle
Water needed in agricultural production
To produce 1 kg of:• wheat = 715 – 750 litres• maize = 540 – 30 litres• Soybeans = 1650 – 2200 litres• Rice = 1550 litres• Beef = 50 000 – 100 000 litres• Wool = 170 000 litres
Agricultural land use in the MDB
See page 49 of your text
Water use for agriculture and income generated, Australia wide
• What uses the most water?• What makes the most money?• What has the best return?
State and territory shares of the basin and their water use
Human and natural uses• In the past, the main role allocated to the river
was to provide water for human use.• Little thought was given to the needs of the
river itself • An unhealthy river = economical and social
impacts & environmental
Unhealthy river
• Dying river red gums• Declining fish numbers• Algal blooms• River not reaching the mouth• Drought
Environmental Flows
• Water allocated to the river for a healthy river• This water has to come from somewhere• Suggested 4000 gigalitres a year needs to be
returned to the river from farm allocations
Gigalitre = 1,000,000,000 litres = 1,000 Megalitres = 1 million litres
Concerns with Environmental flows
• Concerns that returning the water to the river
could lead to the decline of small towns
• Loss of thousands of jobs
• Loss of hundreds of millions of dollars in
economic growth
Does water for the environment have any value?
• A healthy river can have benefits for regional economies and employment
– Providing soil moisture for healthy plant life on riverbanks and flood plains
– Enabling insects to flourish and pollinate crops
– Replenishing aquifers and stabilising river banks through improved tree
cover
– Trees help keep the water table low, which reduces salinity and improves
the level of carbon storage
• http://www.youtube.com/watch?v=Ndpa7nb6Cos
Importance of the MDB
• 10.9% of Australia's population live within the
basin
• 10 % of all people employed in the basin work
in agriculture, compared to 3 % Australia wide
• 38 % of Australian farmers live in the basin
• The mean household income for people in the basin
in 2006 was $675, compared to $732 for Australia
• 3% of Australia’s electricity and 33% of the nations
hydro electricity is generated in the basin
• The Gross value of agricultural production (GVAP) in
the basin was $15 billion (late 2000) or 39% of
Australia’s total value of agricultural products
• 52% of Australia’s total water consumption
was used by industries (including agriculture)
and households in the basin
• Agriculture uses 83% of water in the basin;
households and other industries use 2% each;
the water supply industry uses 13%
Who uses the water?• Water use is unevenly distributed
Biggest regional users on average per year are located in the southern basin:– Murray (4338 Gl)– Murrumbidge (2257 Gl )– Goulburn – Broken (1071 Gl)
Division of water
Adelaide receives 42% of its water supply from the Murray and up to 90% in drought years
7
54
34
5
% water taken from the Murray
SANSWVicQld
• The MDB contains 65% of Australia's irrigated land.
• The long term average use of the basins 1.65 million hectares of irrigated land is
Movement of water
Water is pied to users located outside the MDB in towns like Whyalla, Keith and Woomera in SA
Movement
• In Victoria water is piped from the Goulburn river to Bendigo and Ballarat, and through the North – South pipeline to Melbourne
• otherwise known as the sugarloaf pipeline
See page 54 of text
Snowy Mountains Scheme
• The snowy mountains scheme diverts water from the snowy river to generate hydro electricity
• Increases water supplies in the Murray and Murrumbidgee rivers
Recreation
• Boating• Fishing• Camping• Water skiing• Golfing
Require clean reliable flows and a healthy river
Produce
• People in Australia and overseas consume agricultural products
• Volume of water used for crops and pastures varies from year to year depending on:– Volume available for irrigation– Trading– Commodity prices
Discuss answers to questions 1 – 8 as a class
Activity 9.only Agricultural products which produce very high value returns to irrigators should be allowed in the MDB; all other products should be imported or produced elsewhere in Australia
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