MURRAY DARLING BASIN INTRODUCTION TO ISSUES

MURRAY DARLING BASIN

The Murray Darling Basin is the area of land that makes up the catchment of the River Murray, the Darling River, and all the small rivers and creeks that flow into them.

The Basin is Australia’s most important agricultural region, producing one third of Australia’s food supply, and is home to about two million people.

The Basin provides drinking water for over three million people, and more than one third of these people live outside the area.

The Basin is so important for Australia that if the region is allowed to continue to deteriorate it will affect every Australian, whether they live in the country or the city.

MDB-FACTSArea 1,061,469 Km2

Population 2 million

Population density 2 people/ Km2

Water supply of 3 million people

Australia’s total area 14% or 1/7th

Australian irrigated crops 75%

Australian commercially grown crops

41%

Key economic activity Agriculture, grazing, tourism

Threats Invasive species, river regulation & fragmentation, salinisation, climate change

Length TOTAL 3,370 KmDarling River (2740km long)River Murray (2530km long) Murrumbidgee River (1690km long).

MDB-WATER QUALITY

Water is the lifeblood of all living things

and its also the lifeblood of the Basin.

People who live and work in the Basin

rely on its water to drink, to wash with,

and to use in their factories. Plants and

animals in the Basin also rely on the

water as part of a healthy

ecosystem in which they live, feed and

breed. Over the years the quality of the

Basin’s water has been degraded. As a

result, it’s rivers may not be able to

continue supplying the water that the

people, plants and animals need to

survive.

DRYLAND

IRRIGATION

MDB- CHALLENGE?The water in the Basin’s rivers

are becoming spoiled, wetlands are drying

up, native fish are struggling to survive and

many areas of land are becoming too salty for

plants to grow.

Some of the major challenges facing the

Murray-Darling

Basin are:

• To improve the quality of the water.• To keep the river systems healthy.• To manage the land in a way that provides

jobs for the community, while at the same time taking care of the environment.

SALTWith salinity levels rising in the rivers, as well

as on land, salt is one of the biggest challenges

for the Basin. Salts that naturally occur deep

in the soil are being dissolved by rising

groundwater and then carried into the rivers, or

brought to the soil surface. Most native plants

and crops cannot grow if the soil gets too salty.

If salt levels in the rivers become too high,

plants and fish that live in the water can die.

Salt can also kill crops if farmers irrigate using

salty water from the rivers. The problem is that

huge amounts of native vegetation have been

removed from the Basin over the past hundred

years or so, without being replaced. Shallow-

rooted plants, such as many food crops, do not

use as much rainwater as trees and native

vegetation. The extra rainwater then soaks into the

ground, causing the watertable to rise. When

more trees are planted they use the excess water,

the watertable falls and the land may be able to

recover.

Animals under threat.

Around 30,000 wetlands can be found in

the Basin, some of which are Important

breeding grounds for birds from as far away

as Japan and China! Thirty-five different

native fish species live in the Basin’s rivers.

The Basin has at least 35 endangered

species of birds and 16 species of

endangered mammals. Unfortunately, 20

species of mammals have already become

extinct.

Algal Blooms

When nutrients from fertilisers and drainage flow into the river, it encourages the

naturally-occurring algae to grow faster than usual. Combined with the effects of slow-

moving water from reduced river flows, algal blooms form. This can be a big

problem because some types of blue-green algae are poisonous to humans, animals and

fish. The challenge for Basin managers is to try to stop these blooms from occurring.

SustainabilityAt the moment, there is not enough water

in the Basin to supply everyone’s needs

and wants. The major Water Sharing

Challenge is to come up with a fair

system in which everyone working and

living in the Basin has most of the water

they need, while at the same time,

ensuring that the ecosystem has enough

fresh clean water to thrive. The health of

the river and its tributaries will not be

sustained if the community keeps taking

Large amounts of water out of the river

system to irrigate crops. There is now a

limit placed on how much water can be

removed from the rivers, and members of

the community are learning to balance

their water needs with those of a healthy

and productive environment.

The People Challenge

Who are the people of the Murray-Darling Basin?

• People who live in rural towns and cities

• Farmers

• Indigenous people

• Members of Landcare groups

• People who own and work in businesses and industries

SOCIAL

SOCIALEveryone lives in a catchment area, and a

Healthy catchment is an essential part of a

healthy river. Managing the challenges in

the Basin is not just about managing

rivers. It is also about managing the lands

that make up the catchments of those

rivers to ensure that the system is in

balance. No matter where you live in

Australia, the rain that falls on you will

eventually drain into a river, after

plants have used the water they need and

The ground has soaked up as much as it

can. Problems such as salinity and erosion

on the land will cause salt and soil to be

washed down through the catchment and

into the rivers, degrading river health.

So, another very important challenge for

The people of the Basin is to work towards

healthy ecosystems on the land, as well

as in and near the rivers.

ENVIRONMENTALWhen the natural flows of the river were

changed, plants, fish and animals that had

been happily living there began to suffer.

Thirty-five native fish species live within the

Murray-Darling Basin river system, but

native fish populations are only 10% of what

hey were before European settlement in

Australia. Changes in the flow of the river,

construction of dams and weirs, a decline in

water quality, disappearing habitats,

overfishing, and the introduction of exotic

fish such as carp, as well as of various

made it extremely difficult for many of the

Native species to survive however, there is

a major project under way to send more

water flowing through the Basin’s rivers

so that the environment benefits. This

should help birds and fish to breed again

and may give native vegetation the

opportunity to regenerate.

ECONOMIC

Fifty years ago, people were only

concerned about how to store water

from the Basin’s rivers, and how to

control their flow. The technologies

they developed have made possible

Australia’s multibillion dollar irrigation

industry, which produces one third of

Australia’s food.

The longterm survival of the Basin will depend on our

ability to use its natural resources in a sustainable way.

To achieve sustainability, some people may need

to learn more about the needs of a healthy working

river, and then change the way they use the

resources of the Basin. This will ensure that people are

able to earn a living from using the resources of the

Basin, while at the same time protecting the habitat of

the native birds, animals and fish that also live in the

Basin.

The Murray-Darling Basin Commission is coordinating

community groups. The people who live in the Basin

have different needs and values. They will need to

value what the Basin brings into their lives so that

sustainability into the future becomes a shared goal for

everyone.

ICM- INTEGRATED CATCHMENT MANAGEMENTGovernments and communities throughout the Basin are working together, with the common goal of maintaining this precious environment while, at the same time continuing to grow and develop Basin communities. The sustainable use of the Basin is being managed by the Commonwealth Government, five state and territory governments, and more than 200 local governments. They are working together with people from cities and rural communities, farmers, Indigenous people, Landcare groups and many other community organisations who care about the Basin.

To implement this targets-based approach to catchment health, the capacity of government agencies, catchment management organisations, local government, and the broader community will be strengthened, particularly at catchment scale. Capacity includes legal, institutional, planning, management, financial, technical and information skills and capacities, and leadership skills