General MDB
Importance of water as a resource
• Water is unevenly distributed
• There is a high variability in annual amount of rainfall. Australia's rainfall
in 2009 was 453mm, which was slightly below the long-term average
(1961-1990) of 464mm (BOM 2010b).
• There are high levels of evaporation
• Australia is the driest inhabited continent: 80% arid or semi-arid
• Australia has the second highest per capita consumption of water in the
world. Irrigation is Australia’s major water use
• Australia experienced a 12 year (1998-2010) drought which has been
followed by two years of above average rainfall.
Water Use in Australia
Source: State of the Australian Environment 2006
Irrigated areas of Australia 1997
What are the Geographic characteristics
of the MurrayDarling Basin region ?
“What is there? What is it like?”
• Characteristics might include: location, size, shape
• Natural Features: Slope, soil types, wildlife, vegetation, climate, river Systems
• Human Features: land uses (agriculture, urban), roads, buildings,
infrastructure (dams, irrigation channels)
• Not all regions of the Basin are the same and water availability and water use
vary between regions. Summarise the geographic characteristics of various
sub-regions of the MDB.
• Know the location of some of the major features of the Basin (towns, rivers,
wetlands, agricultural regions) See 2011 Exam Question 1
About the MDB
• Area: The basin covers 1 061 469 km2,
equivalent to 14% of Australia’s landmass or
the size of South Africa.
• It is one of the world’s major river systems.
• It has 6% of Australia’s run-off but more than
half the country’s water use occurs here.
Many rivers contribute
Major tributaries of the Murray Darling.
Source: http://www.anao.gov.au/Publications/Audit-Reports/2010-2011/Restoring-the-Balance-in-the-Murray-Darling-Basin/Audit-brochure
Rainfall varies with seasons
Annual Rainfall in the MDB is unevenly
distributed
Annual Rainfall Murray Darling Basin is
uneven
Source: Bureau of Meteorology 2010 Annual Rainfall - Murray Darling Basin
Annual rainfall is uneven - anomaly's
Distribution of climatic regions
The contribution of water to the
Murray-Darling system is uneven
Source: NP
page 40
Ground water supplements rainfall
Fractured rock
Sedimentary
Surficial
Flows in MDB rivers are naturally
variable
The Darling dried up 48 times at Menindee,
between 1885 and 1960
• Floods Balonne - Jan 2011
The Murray Darling Basin rivers are
floodplain Rivers
rivers
2 Million people live in the MDB
Canbera
Albury Wodonga
Mildura
Water use varies
Corryong – Headwaters of the Murray river
Rice Growing: Griffith NSW
Grape-growing: Griffith NSW
Confluence of Darling and Murray
Rivers, Wentworth
NSW
Murray Gorge - SA
The Coorong and Murray Mouth South
Australia
Example questions and answers
• Describe the Geographic Characteristics of the
MDB?
Not such a good answer
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It’s big
The rivers are long
Farmers grow crops there
Some towns get their water from the river
A lot of people live there.
People have built dams and changed the river.
There are some problems with the water in the
river.
The rivers flow through a few states
Lots of people go there on their holidays
Good answer
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The MDB covers 1 million square kilometres, equivalent to the size of France and Spain(It
extends over75% of NSW, 60% of Victoria ,14% of Qld ,7% of SA,100% of ACT)
The Murray is 2375 kms long and the Darling is 1472 km long
It is a regulated river and in an average year 35% of the total water flow is diverted.
It is naturally salty, but some human activities have increased the amount of salt in the
river.
In other parts of the world the amount of the water in a river increases as the river
approaches the mouth. In the Murray the opposite is the case.
Approx. 2 million people live in the Basin area and many cities and towns rely on the river
for drinking water (including Adelaide)
The MDB produces 40% of the total gross value of Australia’s agricultural product,
including 70% of irrigation production.
Mining and mineral production - $1.66 billion per year
Manufacturing - in excess of $13 billion per year
Forestry - more than $1.2 billion in wood and paper products
Electricity generation - Basin has over 75% of the mainland’s hydro electric power stations
In total, tourism in the MDB is worth over $3444.5 million.