Department of Water
Government of Western Australia
designing a
sustainable water future
The South West Water Plan
An invitation to participate
Department of Water | March 2007
Department of Water
Government of Western Australia
Department of Water
Level 4, 168 St Georges Terrace
Perth Western Australia 6000
www.water.wa.gov.au
Telephone +61-8-6364 7600
Facsimile +61-8-6364 7601
For more information about this document, contact
Roy Stone in Perth on 6364 6833 or Fionnuala Hannon
in Bunbury on 9726 4198.
ACKNOWLEDGEMENTS
The Planning and Policy Division of the Department of
Water would like to acknowledge those organisations who
have contributed to the development of this paper.
In particular:
• Staff from the Department of Water regional office in Bunbury
• Members of the South West Water Forum, the stakeholder representative group established by the Government to provide input to the regional water planning process.
© Department of Water, March 2007
Copies are available by phoning Impact Communications
ph 9227 0233 or can be downloaded from
www.water.wa.gov.au. Copies are also available at Western
Australian public libraries in the South West Region.
SOUTH WEST WATER FORUM,
INVITED ORGANISATIONS
AqWest – Bunbury Water Board
Busselton Water Board
Chamber of Commerce and Industries (SW chapter)
Chamber of Minerals & Energy (SW chapter)
CSIRO Water for a Healthy Country – South West
Fruit Growers Association WA
Forest Industries Federation
Harvey Water
Indigenous NRM Facilitator (SWCC)
Irrigation Association of Australia
Leeuwin Environment Centre
Pastoralists and Graziers Association
Deputy Chair SWCC (Peel-Harvey Catchment Council)
Preston Valley Irrigation Cooperative
Potato Growers of WA Inc.
Shire of Nannup
Shire of Augusta-Margaret River
Shire of Donnybrook-Balingup
Shire of Manjimup
SW Catchment Council
SW Development Commission
SW Environment Centre
SW Land & Sea Council
SW Regional Recreational Fishing Advisory Committee
Trees South West
Urban Development Institute of Australia
Vegetables WA
WA Farmers Federation
Warren Water Advisory Committee
Water Corporation (SW Region)
Whicher Water Resources Management Committee
Wine Industry Association
Government Agencies
Disclaimer
This document has been prepared by the Strategic Water Planning
Branch of the Planning and Policy Division of the Department of
Water. It is provided for information and discussion purposes. It is not a
statement of Western Australian Government policy.
Contents
An invitation to participate..........................................................5
Water resources in the South West Region...................................6
New challenges require new rules and plans...............................9
The State Water Plan..................................................................9
A Regional Water Plan................................................................9
Water resources issues in the South West...................................11
Getting involved ......................................................................22
south west water plan
| An invitation to participate
Designing a Sustainable Water Future
The South West Water Plan
An invitation to participate
Our water resources are essential to the future of the
South West.
They must be managed in a sustainable manner.
The region’s groundwater and surface water resources
provide drinking water to a growing population and allow
industries such as agriculture, mining and tourism to thrive.
They support the ecosystems and biodiversity that make
the South West unique.
They offer opportunities for recreation and possess cultural
and heritage significance.
The water resources of the South West Region are an
integral part of its appeal, and contribute to its ‘clean and
green’ image.
GROUNDWATER comes from rain that soaks
into the ground and is stored in materials such
as gravel, sand and rock. Water can also move
through gravel, sand and rock formations like
sandstone or through cracks in rocks. An AQUIFER
is an earth material that can hold and release a lot
of groundwater. Bores can pump groundwater to
the surface for human uses.
SURFACE WATER is water on the earth’s surface,
such as in a stream, river, lake, or reservoir.
Groundwater and surface water are sometimes
connected. Groundwater can move through
the ground and into a lake or stream. Water
in a lake can soak down into the ground and
become groundwater.
SUSTAINABLE MANAGEMENT
Managing water resources so they can meet
current and future environmental, economic and
social needs.
There are water resources in the region that are in very
good condition. Many are located where large areas of
forest remain and there is little population.
However our groundwater and surface water resources are
finite. They have limits to their availability and suitability
for use.
Human activities have altered many of the region’s water
resources. Not all of the changes have been positive.
Some water resources have experienced problems such as
increased salinity, algal blooms, sedimentation, reductions
in stream flow, and increased acidity.
While some problems remain, there have also been success
stories. For example, the increasing salinity levels of the
Collie River have now been stabilised through active land
management and tree planting over the last 30 years. These
gains need to be protected and further enhanced.
As the pressures on our water resources have increased,
new challenges have emerged. Climate change and acid
sulphate soils are examples of important water resources
issues largely unheard of even 10 years ago.
With so many demands on our water resources, we must
ensure they do not become the subject of a tug of war
among competing interests. The South West Water Plan
will provide a strategic framework and action plan to
guide water resources management in the South West in
the coming years. A draft plan will be released for public
comment in mid-2007.
This document introduces the South West Water Plan and
provides an overview of the water resources challenges facing
the South West. It also identifies ways in which community
members can participate in development of the plan.
We must ensure that we resolve potential conflict between
competing users. We hope that you will register your interest
and become a participant of the Plan’s development, as
detailed on the last page.
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Water resources in the South West Region
Four groundwater management areas define the region’s major groundwater resources. These are the Bunbury, BusseltonCapel, Blackwood and Collie Groundwater Management Areas (Figure 1).
Figure 1. Groundwater Management Areas in the South West Region
A surface water management area (typically a basin or catchment) is the geographic area drained by a river and its
tributaries. There are ten surface water management areas in the South West. These are the Harvey, Collie, Preston,
Capel, Busselton Coast, Lower Blackwood, Middle Blackwood, Donnelly, Warren and Shannon surface water management
areas (Figure 2).
Figure 2. Surface Water Management Areas in the South West Region
south west water plan
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The region has substantial surface water and groundwater
resources, however matching demand with these resources
can prove to be difficult. These resources significantly
contribute to the natural beauty and biodiversity of the
South West.
Over half of all water used in the region is used by
agriculture (an estimated 200 gigalitres a year). While this
includes water for the Harvey, Collie and Preston Valley
irrigation districts, more than half of this use is by farms
outside irrigation districts.
Water use is managed by estimating the amount of water
that can be sustainably extracted from a water resource
in a given period (usually a year). This is known as the
sustainable yield.
Fertile soils, relatively high rainfall, and proximity to the
markets of Perth support a diverse range of agricultural
industries. These include meat, dairy, wool, vegetables,
grains, grapes and fruit.
In the South West, the sustainable yield of the region’s
water resources is estimated to be over 1,000 gigalitres a
year. In contrast to most other parts of the State, over 75%
of this water is held in surface water resources.
The next major water user is mining which accounts for
about 15% (or over 50 gigalitres) of annual regional water
use (Figure 3).
A further 17% of all water used in the South West supports
services to industry (12%) and the community (5%). These
sectors account for water used in industry and small to
medium businesses as well as water used to provide
services to the community including hospitals, schools and
recreational facilities.
Water use in the South West
Currently, 350 gigalitres of water is used annually in the
South West. This represents about 15% of all water used in
Western Australia.
Livestock
1%
Garden bores
3%
Livestock
Households
7%
Parks & Gardens
3%
Services
2%
Industry
12%
Garden bores
Households
Parks and gardens
Services
Industry
Mining
15%
Mining
Irrigated Agriculture
57%
Irrigated Agriculture
Figure 3. Water use by sector in the South West Region
Water for households accounts for 10% of all water
used. Over 140,000 people live and work in the region,
representing 7% of the population of Western Australia.
Mineral extraction and processing is the largest
industry in the South West. Major mining activities
include the extraction of coal, mineral sands, silica,
tantalum, lithium and tin. Mineral processing
is focussed on the production of alumina from
bauxite. Other processing activities include the
manufacture of rutile from ilmenite and titanium
dioxide pigment and silicon.
The State Water Plan
In October 2006, the State Government released the Draft
State Water Plan to guide water resources management to
the year 2030. It sets seven objectives for water resources
management:
• Use and recycle water wisely
• Plan and manage water resources sustainably
• Invest in science, innovation and education
• Protect ecosystems, water quality and resources
• Enhance the security of water for the environment
and use
• Develop water resources for a vibrant economy
• Deliver services for strong and healthy communities.
New challenges require new rules
and plans
The Draft State Water Plan was open for public
comment until 31 January 2007. A copy is available at
www.water.wa.gov.au.
Western Australia is modernising its water legislation, policies
and regulations through a process of water reform.
The State Water Plan will be finalised and released by
Government by mid-2007.
As the pressures on our water resources increase, so do the
challenges in managing them. The outcomes of the water
reform process will better position the State to address the
water resources issues of today and tomorrow.
The process of water reform is moving forward at a rapid
pace. In April 2006, Western Australia joined the National
Water Initiative. Through the initiative, Federal and State
governments are working together to set a common path
for water resources management in Australia.
A Regional Water Plan
Different regions within Western Australia face different water
resources issues. For instance, the water resources issues of
the South West are different from those of the Kimberley or
Mid-West regions. Regional water plans will set out how the
objectives of the State Water Plan will be implemented in
addressing a region’s water resources issues (Figure 4).
The State Government appointed the Water Reform
Implementation Committee to provide advice on water
reform in Western Australia. In July 2006, the committee
released A draft blueprint for water reform in Western
Australia for public comment. Seventeen public workshops
across the State gathered community feedback. This
included workshops in Harvey, Manjimup, Donnybrook,
Busselton and Collie.
The committee provided advice to Government in late
December 2006. The committee’s advice and the
Government’s response will be released in early 2007.
Based on this the State Government will decide how the
water reform agenda will proceed. Among the changes to
water management are the introduction of statutory water
management plans, an improved system of water rights,
expanded water metering, more water trading, greater water
use efficiency and increased community involvement.
south west water plan
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The South West is the setting for the first of the State’s
regional water plans. Figure 5 shows the geographic
boundaries of the South West Water Plan. The objectives
of the plan are to:
Water management plans focused on specific water
resources and management issues will support the South
West Water Plan (Figure 4). There are four types of
management plans:
• Assess the status of water resources management in
the South West
• Statutory Water Management Plans
• Examine social, economic and environmental trends
that will influence future water management decisions
in the region
• Drainage Plans
• Assess the region’s water availability for regional and
broader water demands
• Determine priority actions to improve resources
management in the South West
• Drinking Water Source Protection Plans
• Floodplain Management Plans.
Strategic Water Issues Plans from government, and water
user and community plans, will also inform the South West
Water Plan.
• Examine the impact of the State’s water reform process
on the South West.
State Water Plan
Water user and
community plans
Strategic Water
Issues Plans
Regional Water Plans
Statutory Water
Mangement
Plans
Drinking Water
Source Protection
Plans
Drainage Plans
eg South West Groundwater
Areas Plan (Bunbury-Busselton
& Blackwood)
eg Bunbury Water Reserve
Bunbury-Busselton Water
Source Protection Plan WRP
43 (draft)
A planning framework is being
developed
Figure 4. Three levels of water plans
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Floodplain
Management
Plans
eg Busselton Floodplain
Management Strategy
Water resource issues in the South West
Reduced rainfall and climate change
Everyone has heard of climate change, but how it will affect our water resources is not clear. However, we do know that since
the mid-1970s, winter rainfall in parts of the South West has decreased by 10-15 per cent. This may not seem like much,
but even a small decrease in annual rainfall can result in a significant decrease in the amount of water in our rivers and
groundwater. This is because only a small proportion of rainfall ever becomes stream flow or percolates to groundwater.
Figure 5. South West Region boundaries
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CLIMATE CHANGE refers to long-term changes
in temperature and weather patterns. It can
be caused by both natural forces and human
activities. Current science indicates a link between
climate change and the burning of fossil fuels.
Climate change is sometimes referred to as “global
warming” or the “greenhouse effect”.
The reduction in stream flows in the South West has
been variable. The greatest decreases have occurred in
the higher rainfall areas. In some locations, the decline
in stream flows has been dramatic. Figure 6 shows that
stream flow in the Harris River near Collie has declined
greatly since the mid-1970s. In the early 1990s, the Harris
River has only one-third of the stream flow it experienced
before 1976.
Climate change models developed by the CSIRO indicate
further reductions in rainfall and increases in temperature
are likely. By 2030, rainfall may have decreased by as
much as 20 per cent relative to 1990. This may reach as
high as 60 per cent by 2070.
| An invitation to participate
A combination of less rainfall with higher temperatures would
decrease the amount of water available and increase demand
for water. Surface water resources and shallow aquifers
are more vulnerable to impact than deeper groundwater
resources. If the water table drops, wetlands will become
drier and bores may need to be drilled deeper. Reduced fresh
water runoff may increase stream salinity levels.
Water resources managers must account for climate
change in their planning. This is not an easy task. It is not
yet possible to predict with a high level of certainty what
impact climate change will have on water resources in the
South West. However, our state of knowledge is improving
through the efforts of programs such as the Indian Ocean
Climate Initiative.
THE INDIAN OCEAN CLIMATE INITIATIVE
promotes the sharing of the latest research
findings on climate variability and change in WA.
Created by the State Government in 1998, it is
a partnership of State Government agencies, the
CSIRO, and the Bureau of Meteorology.
Website: www.ioci.org.au
Mean monthly flow (GL)
10
8
1958-1975
6
1976-1992
4
2
0
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Figure 6. Decline in Harris River stream flows
Stream gauging station closed in 1993 due to construction of Harris Dam.
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Protecting and managing waterways
and wetlands
South Western Australia is a global biodiversity hotspot,
and the waterways, wetlands and other water dependent
ecosystems (eg cave ecosystems) of the region are
fundamental to this global significance. They provide
habitat for aquatic and terrestrial flora and fauna, support
biodiversity and are significant assets for the South West
Region. Water dependent ecosystems are also significant
assets of the South West Region because they:
• drain land, transport and store water and carry
flood waters
• provide opportunities for recreation and community
activities
• provide a source of water for drinking, fisheries,
aquaculture, agriculture, mining and other types
of industries
• are a significant part of Indigenous and nonIndigenous heritage
• provide distinctive landscape features and have
aesthetic values.
The South West Region contains some high conservation
value waterways and wetlands including Lake Preston (part
of the Peel-Yalgorup System) and the Vasse-Wonnerup
Ramsar wetlands; and wetlands and waterways in the
Directory of Important Wetlands, including Benger Swamp,
McCarley’s Swamp (Ludlow Swamp), Blackwood River
(Lower Reaches) and Tributaries System, Gingilup-Jasper
Wetland System, Doggerup Creek System, Maringup Lake,
Broke Inlet and the Lake Muir-Byenup Lagoon System; and
water dependent systems in the conservation estate.
Sustainable management is required to ensure the values
of waterways, wetlands and other water dependent
ecosystems are maintained. In the Region, many natural
water bodies have become unhealthy or degraded due to
loss of wetland and riparian vegetation, soil erosion and
sedimentation (eg filling in river pools and channels), weed
invasion, regulation of rivers by dams and other flow control
structures, altered water regimes (due to abstraction,
irrigation, drainage and the drying climate), altered fire
regimes and reduced water quality (eg increased salinity
and nutrients).
Restoration and protection of these natural water
bodies is encouraged to maintain or enhance significant
values. In particular, this should be undertaken at
an early stage, to minimise the need for more costly
remedial work in future.
Drainage management and flood protection
Drainage management systems collect and transport
water from natural and modified water bodies in the
landscape. In urban, commercial and industrial areas,
these systems are used for stormwater, groundwater and
flood management. In rural areas, constructed drainage
systems may be used for irrigation (eg Harvey) and to
drain waterlogged agricultural soils, manage salinity or
control flooding.
Drainage should be managed to protect the health of
receiving water bodies (ie waterways, wetlands, marine
environments and other water dependent ecosystems).
For example, current best practice in urban (ie residential,
commercial and industrial) and rural-residential areas
requires that drainage management should minimise
potential changes in the volume of surface water flows
and peak flows resulting from land development. This
is important because, if not managed appropriately,
drainage can have adverse impacts on water regime,
water quality, habitat diversity and biodiversity in
receiving water bodies. The best practice approach
replicates natural drainage processes, and is different to
the traditional drainage management approach of using
constructed, piped drainage and channels that discharge
to receiving water bodies.
A CONSUMPTIVE WATER USE involves the
withdrawal or diversion of water from a surface water
or groundwater resource. The water may be used for:
• Domestic and residential uses
• Industrial uses
• Agricultural uses
• Power generation
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south west water plan
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How much water is needed?
An area cannot continue to develop if water demand
outstrips water supply.
In the South West, increases in demand for water supply
are most likely to come from three sources: population
growth, agriculture, and mining and mineral processing.
Currently, as shown in Figure 3, irrigated agriculture is
the largest water user in the South West. The mining
sector is next.
Population Growth
The South West’s 140,000 residents comprise seven per
cent of the State’s population. The region has experienced
significant population growth over the past 20 years,
especially in areas such as Bunbury, Busselton and the
Margaret River area. The region’s population is projected
to reach 175,000 by 2021. The greatest growth is expected
in the Greater Bunbury area, the Bunbury to Busselton
coastal area, and the Shire of Augusta-Margaret River.
Despite water conservation efforts, increases in population
will increase the demand for public water supply. Some
communities, such as Margaret River, are nearing the
limits of their current public water supplies and will need to
find additional resources in the near future.
Three service providers supply water to towns in the South
West. Aqwest (ie Bunbury Water Board), the Busselton
Water Board and Water Corporation provide drinking
water to over 90,000 properties in the region. Aqwest
and the Busselton Water Board draw their supplies from
groundwater resources. Water Corporation relies primarily
on surface water from dams along the Darling Scarp or
locally sourced groundwater or surface water.
Water Corporation also supplies water to the Greater Perth
area via the Integrated Water Supply System (IWSS).
For many years, Water Corporation dams along the Darling
Scarp have contributed drinking water to the IWSS as well
as irrigation water to the Waroona, Harvey and Collie
irrigation districts.
14
The Environmental Protection Authority has reported
its recommendations to Government on the Water
Corporation’s application to source a large volume of
groundwater (ie 45 gigalitres/year) from the south west
Yarragadee Aquifer. The Department of Water will advise
Government on use and management of the South West
Region’s water resources.
By 2021, the Greater Perth area (ie Metropolitan Perth,
Mandurah and Murray) will be home to an estimated
two million people. The additional population will increase
the demand for public water supply in that region. Water
resources in the South West may be used to meet some of
that demand. One possible source is the Wellington Dam
near Collie. The State Government has established an
independent steering committee to provide advice on the
best uses of this water resource in the longer term.
Agriculture
There are important agricultural areas in the South West
on the Swan Coastal Plain, between Cape Naturaliste
and Cape Leeuwin, on the Scott Coastal Plain and in the
Pemberton-Manjimup area.
A GIGALITRE (GL) of water is 1,000 million
litres. A MEGALITRE (ML) of water is a
million litres.
Changing economic conditions have resulted in fewer
but larger farms and a gradual shift from grazing to
horticultural crops.
The volatility of the agricultural sector makes predictions of
future water demands difficult. Some experts predict growth
in the agricultural sector and increased demand for water.
Others are less optimistic, pointing to deregulation of the
dairy industry, a slowing in the viticulture sector, and foreign
competition in the marketplace as signs of a weaker future.
Mining and processing
In terms of gross regional product, mineral extraction
and processing is the leading economic sector in the
South West. Mineral sands mining occurs in coastal areas
(Busselton-Capel), with bauxite and coal mined inland.
Coal-based power generation and alumina production
are continuing to expand, while heavy mineral sands
production is relatively stable. Coal mining and electric
power generation are major users of groundwater in the
Collie area. Groundwater abstraction in the Collie Basin
has generally exceeded the volume of water entering the
groundwater system.
MEASURING WATER USE
A likely outcome of the water reform process is more
water metering in WA. Currently, only licensed use
by large water users (ie above 500 ML/yr) requires
metering. It is proposed that medium-size water
users (ie above 50 ML/yr) also be metered. The
additional metering will provide a more accurate
picture of the amount of water withdrawn from a
water resource. Private garden bores and water
withdrawn for small-scale domestic and livestock
use will generally remain unmetered.
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Doing more with less
Alternative water resources such as treated wastewater can
reduce the pressure on groundwater and surface water
resources to meet future demand for consumptive water.
Water resources managers also look for ways to reduce the
demand for consumptive water use.
Water recycling makes the most of water resources that
too often in the past have been wasted.
GREYWATER is waste water from the kitchen,
laundry and bathroom (but not the toilet).
Stormwater, greywater, rainwater and treated sewage are all
alternative water supplies. With appropriate treatment, these
water resources are suitable for a range of purposes. This
includes irrigating pasture and crops, industrial processing,
and to keep our public and recreational spaces green.
Some South West communities already use treated
wastewater to supply water for tree lots, golf courses and
sports ovals. The South West Water Plan will identify how
water recycling can be further encouraged.
WATER SENSITIVE URBAN DESIGN
Poor management of stormwater can result in
flooding and reduced water quality. In urban
areas, solid surfaces (eg roads and parking
areas) result in a large percentage of rainfall
running off into the drainage system. This water
can carry a variety of contaminants. These
include litter, detergents from people washing
their cars, nutrients and heavy metals. They
can eventually find their way into local rivers,
wetlands and estuaries.
Water sensitive urban design (WSUD) offers an
alternative approach to stormwater management.
It treats stormwater as a resource rather than
a nuisance. Hard surfaces are minimized and
stormwater is reused on site. Vegetated areas aid
water infiltration and removing pollutants.
Our water resources are limited. Yet, too often, we are
wasteful in our use of water.
Initiatives such as the State Government-sponsored Water
Wise on the Farm program are working with South West
farmers to improve water use efficiency through new
irrigation technology and best management practices.
The Harvey Water irrigation co-operative is another
example of improved efficiency in the agriculture sector.
The irrigation system’s open channel delivery system
had experienced water losses of up to 31 per cent due to
evaporation and leakage. By progressively converting to
a pipe system, Harvey Water is dramatically reducing its
water losses. The water savings will be made available to
the Water Corporation to lessen the demand pressures on
groundwater and surface water resources.
The WATERWISE REBATE PROGRAM offers
refunds of up to 50 per cent on a variety of
‘waterwise’ products. These range from swimming
pool covers and irrigation systems to showerheads
and washing machines. To learn more about how
to obtain a rebate, visit www.water.wa.gov.au or
call Water Corporation on 1300 133 646.
Greater water use efficiency is needed in both urban and
rural areas and across all sectors of water use (eg domestic
use; industry; agriculture). The South West Water Plan will
identify and support priority actions to achieve greater
water use efficiency in the South West.
How much water can be taken?
Failure to respect the sustainable limits of a water resource
can result in over allocation and over use. Over allocation
may occur when the amount of water withdrawn from a
resource is greater than its ability to replenish itself.
Some water needs to remain in the system to support
dependent ecosystems and in-stream social benefits
such as cultural and recreational values. Over allocation
may occur when the stress placed on a water resource is
greater than it can handle. For instance, too many nutrients
entering the water results in algal blooms and fish kills.
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south west water plan
Both over allocation and over use threaten the health of
ecosystems and the social and economic uses supported
by the water resource.
Scientific investigations are used to understand how a
particular water resource functions. Hydrogeologists and
hydrologists study the movement of groundwater and
surface water and its physical and chemical characteristics.
They use historical water records and observations of
hydrologic processes (eg rainfall or river flow) to predict
future water conditions and events. Ecologists investigate
the relationship between water resources and the plant
and animal species that depend on them. Ecological
studies determine issues such as the amount of stream
flow needed to maintain fish populations and habitat.
Resource managers examine what impact various levels
of water abstraction and use would have on various water
users and the natural environment. The better the scientific
understanding of a water resource, the more confident
resource managers can be in setting sustainable limits to
water abstraction and use. Once the sustainable limits of
use are established, the water resource is monitored. This
is to ensure environmental objectives are achieved and
water users meet their obligations (eg releasing water to
downstream users).
Further hydrological and ecological investigations are
needed to support water resources management decisions
in the South West. The need is greatest for those water
resources that are both in high demand for consumptive
use and support high-value ecosystems.
Drinking water source protection
Some groundwater and surface water sources are
designated for use as public drinking water. It is particularly
important to protect these sources from contamination
and reduce the need for costly treatment.
Land use and recreational activities that pose a potential
risk of contamination are kept away from sources of drinking
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The water that runs off AGRICULTURAL
LAND contains the chemicals used by farmers,
as well as animal wastes. RECREATIONAL
ACTIVITIES such as swimming and fishing
in reservoirs can introduce bacteria and
organisms that are a risk to public health.
water. Drinking Water Source Protection Plans put in place
measures to reduce the risk of water contamination.
Fewer restrictions are placed on activities near water
resources used for other purposes. Some reservoirs used
for irrigation have become important outdoor recreation
venues. Fishing, marronning, swimming, water skiing and
canoeing are popular activities at these reservoirs.
The demand for water-based recreation activities in the
South West is increasing. There is also pressure to convert
some reservoirs used for irrigation to use for public drinking
water. The potential for conflict exists as many recreational
activities are prohibited in drinking water reservoirs.
Currently, not all public drinking water sources have
protection plans. The South West Water Plan will outline
the priorities for development of source protection plans
for drinking water sources.
Acid sulphate soils
The soils of both the Swan and Scott Coastal Plains
contain iron sulphide minerals. These naturally occurring
substances do not pose a risk to water quality if left
undisturbed. However, drainage and excavation of these
soils for agriculture or urban development exposes these
minerals to air.
The sulphides oxidise producing sulphuric acid, hence the
name acid sulphate soils. The soil can neutralise some of
the sulphuric acid. However, the remainder moves through
the soil, acidifying groundwater and eventually surface
water. As sulphuric acid moves through the soil, it strips
iron, aluminium and heavy metals from the soil.
Low-lying areas near estuaries and wetlands
are more susceptible to acid sulphate soils.
If streams, wetlands and rivers become acidic, fish and
other aquatic life will suffer. Fish kills are the most obvious
effect. More common but less visible effects include slowed
growth and reduced reproduction.
Acid sulphate soils also reduce farm productivity. Some soil
nutrients become less available to plants. By drinking acidic
water, grazing animals may take in too much aluminium
and iron.
The risk posed by acid sulphate soils has started to
become better understood in recent years. Land and water
planners are still developing ways to manage the risk of
acid sulphate soils.
Tree plantations and farm dams
The number of tree plantations and farm dams has grown
dramatically in the South West. Both are significant water
interception activities. Tree plantations intercept rainfall
and/or use deep roots to access an aquifer. Farm dams
intercept and store overland flows.
In areas such as the Collie catchment, tree plantations are
used to improve water quality by reducing the mobilization
of salt.
The area of tree plantations in private ownership
now exceeds that in public ownership.
In other parts of the South West, private tree plantations
have become popular, not for salinity management, but as
commercial ventures. This growth is driven by the popularity
of managed investment schemes. Plantations are also
an option for farmers looking to move out of traditional
agriculture or wanting to diversify their operations.
Some in the South West have voiced fears that more tree
plantations may reduce stream flows, leaving less water for
other water users and the environment.
Tree plantations and off-stream farm dams can affect the
amount of water available for other uses. Where a water
resource is nearing or has reached its limit of abstraction,
the amount of water intercepted by tree plantations and
off-stream farm dams needs to be taken into account in
water management plans. The State’s water reform process
is examining how best to manage water interception. This
includes determining what regulations should apply.
Reducing river salinity
Decades of land clearing have contributed to increased
salinity levels in many rivers in the South West. When water
becomes too salty it is not suitable for some uses, including
drinking water. The maximum allowable salt level in water
used for public drinking water is 500 milligrams per litre
(mg/L). Salinity in the Warren River is about 800 mg/L and
the Wellington Reservoir is about 1,000 mg/L.
As part of the State Salinity Strategy, both the Warren and
Collie River catchments are undergoing intensive efforts
to reduce salinity levels. Community-based management
committees are evaluating and implementing management
options to restore these water bodies to a fresh condition
within the next 10-25 years.
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south west water plan
Nutrients and algal blooms
Algal blooms can affect human health and impair the
environmental, recreational, tourism and fishery values of
waterways and wetlands. They can cause water discolouration
from surface scums, harm aquatic flora and fauna and
impede boat access. They can accumulate on beaches and
in shallow waters, creating foul odours as they decay.
Several key factors promote algal bloom growth, including
high nutrients, calm water, high temperatures and an
unhealthy environment. Reduction of nutrients in the
catchment, for example by encouraging sound farm water
and nutrient practices and restoring natural waterways
and wetlands, is vital to reduce algal growth.
In the South West Region, waterways that require action
to reduce the adverse impacts from algal blooms include
the Vasse River, Leschenault Inlet, Margaret River and
Hardy Inlet.
Partnering with the community
Finding and implementing the solutions to the water
resources issues of the South West will require collaboration
between multiple government and non-government
organisations. It is important that the South West Water
Plan complements other natural resource management
and land use planning efforts in the South West.
The Department of Water will continue to engage with
a broad range of community stakeholders during the
development of the South West Water Plan. This will
include meetings with individual governmental and nongovernmental organisations, through working groups
dealing with specific issues, by way of the South West
Water Forum, and through water planning workshops in
communities in the South West.
The South West Water Forum brings the Department and
regional stakeholders together to discuss water resources
issues and management priorities in the South West.
The Forum includes representatives from agriculture,
catchment councils, business and industry, Aboriginal
interests, local governments, fishing, water service
providers and forestry. The Forum has already met for
three planning sessions and will continue to meet until the
South West Water Plan is in place.
Involving the community in water resources management
is simply good practice. Local communities are sources
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| An invitation to participate
of knowledge and expertise in their own right. They can
play a vital role in identifying key issues and helping
shape solutions. They help ensure that State Government
decisions reflect local values.
The Department meets regularly with two Governmentappointed committees of community representatives. The
Whicher Water Resources Management Committee and
the Warren Water Advisory Committee provide advice to
the Department of Water on water resources issues in the
South West. They have become models of the significant
contributions community members can make to resolving
local water resources issues.
The South West Water Plan will examine the aspirations
and roles of the community in local water resources
management.
Timeline for Plan Development
2006
Mar-Nov
Preparation of background papers on water resource management in the South West (see Links
to further information below)
2007
March
Release of The South West Water Plan – an Invitation to Participate
Jan-Apr
Consultation with regional stakeholders and data analysis
May-June
Community workshops conducted in the South West
Mid year
Release of the draft South West Water Plan for public comment
Late year
The South West Water Plan is finalised ready for release by Government
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south west water plan
Getting involved
As a community member, you can become involved in the
South West Water Plan by:
• Visiting the web site for the South West Water Plan:
www.water.wa.gov.au.
• Joining our participants’ register so you can be
contacted when events such as workshops are
scheduled or reports become available. You may do this
by visiting the web site for the South West Water Plan:
www.water.wa.gov and clicking on the participants’
button, or by phoning Mrs Linley Buchanan of Impact
Communications Public Relations on 9227 0233 and
giving your contact details.
• Attending a South West Water Workshop. The public
workshops will be advertised in local newspapers in
March and April 2007.
If you would like to speak with a member of the study team
preparing the South West Water Plan, please contact Roy
Stone in Perth on 6364 6833 or Fionnuala Hannon in
Bunbury on 9726 4198.
Links to further information
The following documents can be found on the Department
of Water web site www.water.wa.gov.au:
The South West Water Plan
South West Water Plan background papers:
• A Regional Overview
• An Overview of Water Policy
• A Review of Future Trends.
Draft State Water Plan
Draft Blueprint for Water Reform in Western Australia
Indian Ocean Climate Initiative, go to:
http://www.ioci.org.au/index.html
Thank you for taking the time to read
this document
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| An invitation to participate
23
Perth office:
168 St Georges Terrace, Perth, Western Australia
Telephone: (08) 6364 7600
South West Regional Office:
35-39 McCombe Road, Bunbury
Telephone: (08) 9726 4111
w w w. w a t e r. w a . g o v. a u