water forever

OPTIONS FOR OUR WATER FUTUREAPRIL 2008

CONTENTS

01 INTRODUCTION

02 WATER FUTURES

03 CONSERVE

04 CONNECT

05 CREATE

06 TOWARDS IMPLEMENTATION

07 INFORMATION SHEETS

1OPTIONS FOR OUR WATER FUTURE

03

10

21

35

47

63

68

There are a number of ways you can have your say on our

50 year plan.

1. Visit www.watercorporation.com.au/waterforever to

register and fi ll out the online feedback form.

WAYS TO HAVE YOUR SAY

ON WATER FOREVER

Water Forever is the Water Corporation’s 50 year plan to

deliver water services to Perth and surrounding areas.

2. Write to us at:

Water Forever

Water Corporation

Locked Bag 2

Osborne Park Delivery Centre

WA 6916.

Public submissions close on 30 June 2008.

2

VOLUMES OF WATER

One litre 1 litre 1 litre

One thousand litres 1,000 litres 1 kilolitre

One million litres 1,000,000 litres 1 megalitre

One thousand million litres 1,000,000,000 litres 1 gigalitre

INTRODUCTION

Enhancing the security and reliability of our water supplies

is important to all of us.

Effective management of water helps to provide essential

water services to the community while preserving the

environment and our cultural and spiritual values. Western

Australia is growing rapidly and is expected to continue

to do so in the foreseeable future. Planning for our water

needs supports the development of healthy communities.

The State Government has given water and the

management of water resources strategic priority. This will

continue given climate change and variability, resource

scarcity and continued increases in demand.

Water Forever is happening at a time of signifi cant investment

in water resource management in Western Australia.

This section provides context for this project by outlining

other strategic water plans in the study area and the role of

the Department of Water as the resource manager. It also

outlines the project scope, study area, previous planning

work undertaken and the framework for sustainable

decisions to support our water future.

STATE WATER PLAN

In May 2007, the Western Australian Government released

the State Water Plan 2007. It summarised the State’s existing

knowledge of water resources, water demands and use, and

the experience of climate change. The plan outlined water

policy and planning frameworks to integrate reforms at state

and national levels.

The plan also outlined 100 priority actions to implement

these changes. One of these is for the Water Corporation to

engage with the community on water source options for the

Integrated Water Supply Scheme.

Water Forever is this initiative.

The Department of Water is coordinating the implementation

of the State Water Plan 2007. They are also responsible for

developing two strategic water resource plans occurring in

the Perth area. These are the Perth - Peel Regional Water

Plan and the Gnangara Sustainability Strategy.

WORKING WITH THE DEPARTMENT OF WATER

The Water Corporation works together with the Department

of Water, Department for Planning and Infrastructure and

other agencies to plan for water services for our customers.

The Department of Water coordinates the water-planning

framework outlined in the State Water Plan 2007.

WESTERN AUSTRALIAN WATER PLANNING FRAMEWORK

The Department of Water also develops water resources

and water industry policy in Western Australia. National

frameworks including the National Water Initiative inform

outcomes in these areas. The Department of Water is

responsible for:

• water resource investigation and assessment;

• water accounting;

• licensing water use;

• wetlands and waterways;

• drainage planning;

• fl oodplain management;

• water industry policy, including pricing policy; and

• water legislation.

The Water Corporation is one water user, licensed by the

Department of Water. There are roughly 14,200 licensed

water users in Western Australia, from sectors including

mining, agriculture, Local Government, industry and

service organisations. Over 90% of these licenses are for

groundwater use, and the remainder for surface water use.

The Department of Water also manages unlicensed water

use, such as small farm water supplies and garden bores.

Water Forever will primarily focus on the needs of our

customers – residents, businesses and organisations

connected to our schemes. Where possible, we will consider

how we can enhance the environment and provide services

to other water users where there is a need.

At the same time, the Department of Water is working on

an overarching regional water plan, the Perth - Peel Regional

Water Plan. This plan will review water resource planning in

the region and provide guidance on strategic water issues,

policy options and management priorities in the region. One

of the issues under consideration in this plan is allocating

water for public water supply.

4

OPTIONS FOR OUR WATER FUTURE

Other issues that have been identifi ed for the Perth - Peel

Regional Water Plan include climate change, water demand

and availability, water use effi ciency and recycling, urban

corridor development and protecting waterways and wetlands.

As the Perth - Peel Regional Water Plan progresses, Water

Forever will be updated by research and investigations

conducted on key issues and the emerging priorities. A draft

is expected to be released for public comment later this year.

WORKING WITH THE GNANGARA SUSTAINABILITY STRATEGY

The Gnangara Groundwater System is a series of

groundwater resources and wetlands that extends from the

north banks of the Swan River to Moore River, north of Perth.

The Gnangara Groundwater System underpins the water grid

and has provided up to 60% of total scheme water supply to

Perth, the Goldfi elds and surrounding communities.

Parts of this system are under pressure due to the combined

impacts of a drying climate, land use changes and water

abstraction. On average, over the past few years, the Water

Corporation has drawn about 150 gigalitres a year from the

Gnangara Groundwater System for the water grid. This is

about 40% of the estimated total water abstracted from the

Gnangara Groundwater System by all users (licensed and

unlicensed).

In 2007, the State Government initiated the Gnangara

Sustainability Strategy to review land and water use in the

Gnangara area. This initiative is being led by the Department

of Water. Participating agencies include the Department for

Planning and Infrastructure, Department of Agriculture and

Food, Department of Environment and Conservation and the

Water Corporation.

The Water Corporation supports the development of this

strategy to provide a sustainable water resource management

approach for the Gnangara Groundwater System. Decisions

made as a result of the strategy will impact the role that this

resource plays in public water supply for the Integrated Water

Supply Scheme (IWSS) water grid.

The Gnangara Sustainability Strategy is examining a wide

range of options to integrate land and water planning

in this area. The strategy is expected to be fi nalised for

consideration by Government in mid-2009.

STRATEGIC LAND PLANNING

Over the past 50 years four strategic plans have been

developed by Western Australian land planning agencies to

guide land development in the Perth region:

• Stephenson and Hepburn’s plan in 1955;

• The Corridor Plan in 1970;

• Metroplan in 1990; and

• Network City in 2004.

The fi rst three plans supported development of a rapidly

expanding city.

Network City builds on this objective and considers land

development impacts due to growth, climate change,

loss of biodiversity and the need to conserve energy and

water. It is a strategic planning document jointly released

by the Western Australian Planning Commission and the

Department for Planning and Infrastructure, as a result of

extensive research, planning and community engagement.

It provides strategic direction for land planning in the

metropolitan area based on a range of sound principles:

• bringing people together around activity centres;

• connecting people and places with networks;

• building a sense of place and belonging in

communities; and

• protecting the natural environment to sustain the city.

The Network City vision for Perth and Peel is:

“That by 2030, Perth people will have created a world-class

sustainable city, vibrant, more compact and accessible, with

a unique sense of place.”

There are three principles to guide decision-making:

• enhance effi ciency of urban land use and infrastructure;

• protect the environment and improve resource effi ciency

and energy use; and

• enhance community vitality and cohesiveness.

The approach encourages a more compact city by making

better use of existing land in developed suburbs. This

reduces urban sprawl and can have very positive impacts on

water use effi ciency as well as infrastructure effi ciency. Water

Forever seeks to align with the principles of Network City.

We are monitoring the extent to which these land planning

principles are being achieved. They directly impact the

timing, location and extent of further investment in water,

wastewater and drainage infrastructure.

5

WATER FOREVER

Water Forever is developing a long-term plan for Perth

integrating water, wastewater and drainage services with

land planning. We’re thinking 50 years ahead and the plan

will outline actions to support water service delivery in three

horizons:

• 10 years to 2020;

• 20 years 2030; and

• 50 years to 2060.

Water Forever will create a framework for the delivery of

conservation initiatives and infrastructure to support our

water future. The plan will need to be comprehensive and

fl exible to adapt to our changing environment.

LINKS WITH PREVIOUS STUDIES

The effects of a drying climate and prolonged drought across

Australia are creating a realisation that rainfall dependent

sources of water may not provide enough water, or enough

certainty, to meet the needs of growing cities. There is a

need to balance reliable water sources with a responsible

level of demand.

Refl ecting different climate scenarios and choosing between

a number of options requires an effective and dynamic

means of evaluating a portfolio of water use effi ciency and

water supply options. This includes comparing the risks and

costs to the community with different options.

Over the past fi fteen years, the Water Corporation has

completed several strategic infrastructure-planning

documents that have formed the basis for ongoing

investment in new programs and infrastructure:

• Perth’s Water Future: A water supply strategy for Perth

and Mandurah, 1995;

• Wastewater 2040, Strategy for the Perth Region, 1995;

and the

• Integrated Water Supply Scheme, Source Development

Plan, 2005.

The Source Development Plan adopted an integrated

resource planning approach as recommended in the State

Water Strategy released in 2003. Integrated resource

planning ensures that options to reduce demand on

water supplies (such as water use effi ciency initiatives) are

compared on an equal basis with options that increase

supply (such as new water sources).

This framework has been developed by urban water utilities

across Australia to evaluate a range of options.

Water Forever will be examining a range of water source

and water use effi ciency initiatives that could help to meet

demand over the next 50 years. Information sheets have been

developed for a range of water source and water use effi ciency

options that address sustainability considerations, cost and

potential yield (the amount of water available for use).

The direction provided in the above mentioned planning

reports have helped us to keep pace with development.

We have been able to meet your water service needs by

implementing a range of water use effi ciency and customer

service initiatives, coupled with detailed asset planning and

development of existing or new water sources.

It is now time to review these plans and move forward once

again.

PROJECT SCOPE

The study area covers three quarters of all our customers in

Western Australia.

In Western Australia regional areas have very different

climates, communities, economic needs, water resources

and ecosystems. Where there is a need for a separate water

service plan for a particular region, this will be addressed in

a study designed to meet the needs of that region and its

community. For example, the Water Corporation is currently

examining options for the Pilbara.

Water Forever will cover the area currently supplied by the

IWSS water grid, which includes the area supplied by the

Goldfi elds and Agricultural water pipeline. The wastewater

planning area is the current metropolitan area, from Lancelin

in the north to Mandurah in the south. The project will

consider opportunities for more water recycling in these

areas. Drainage catchments in the Perth and Peel areas are

also in this scope.

These planning areas will consider nearby communities that

could be connected to the IWSS water grid or wastewater

schemes in the future.

6

OPTIONS FOR OUR WATER FUTURE 7

STUDY AREA

8

TOWARDS A SUSTAINABLE WATER FUTURE

The Water Corporation understands the need to deliver

sustainable outcomes when planning for water, wastewater

and drainage services. It is our responsibility to provide our

customers with a safe and reliable water supply, drainage

and wastewater services. We aim to provide water solutions

that deliver a ‘quality of life’ for customers and surrounding

communities, which is environmentally responsible and

affordable for current and future generations.

For many years we have considered issues in light of

environmental, social and economic impacts. Our purpose is:

“The sustainable management of water services to make

Western Australia a great place to live and invest.”

In defi ning ‘sustainability’, the Water Corporation has

adopted the defi nition outlined in the Western Australian

State Sustainability Strategy, ‘Hope for the Future (2003)’:

SOCIAL

ECONOMIC

E

NV

IRO

NM

EN

TAL

SIGNIFICANTLY ACHIEVED

SustainableManagement

of WaterServices

Enhance the resilience of the

natural and humanenvironment Enhance

communitycapacity

Enhancethe economicvalue to ourcustomers,

suppliers & thecommunity while

deliveringshareholder returns

Protect the healthand safety of all& support the

wellbeing of ouremployees &

customers

PREVENT

SUSTAIN

ENHANCE

Preserve ourcapacity to providewater services to

meet present and future needsPrevent harm

to theenvironment

Respectthe value

of all

Find efficienciesthat reduce internal and external costs

Conserve thevalue of theenvironment

PART

IALL

Y A

CHIE

VED

“Sustainability is meeting the needs of the current and

future generations through integration of environmental

protection, social advancement and economic prosperity.”

The Water Corporation has developed a Sustainability

Strategy to build awareness and understanding, encourage

sustainability thinking in the organisation and embed

sustainability principles into decision-making processes.

Business principles have been designed to guide planning

and operations by identifying issues, generating options

for development, engaging with stakeholders, evaluating

options and making decisions.

Practical outcomes achieved so far include creating the

Security through Diversity approach to meet water needs

in a drying climate. We have also used these principles to

develop a Greenhouse Strategy.

Water Forever is adopting these business principles for

sustainability to guide the development of the project,

community engagement and decision-making.

IMPLEMENTATION

When complete, Water Forever will detail actions to

implement the plan, including linkages with land planning.

OPTIONS FOR OUR WATER FUTURE 9

THE WATER FOREVER ENGAGEMENT PROCESS

Do you want to be involved in making decisions about

water and wastewater services for Perth?

Get Involved Throughout the project

What are the major issues that need to be addressed in

relation to water and wastewater services for Perth?

Have your say March - June 2008

Here is a summary of your input into planning to date. What you said July - August 2008

Here is a draft plan, that indicates where we’re heading.

Do you agree with the direction we’re proposing to take?

What we plan to do Late 2008 - March 2009

Here is our fi nal plan and how we will implement the

strategy, developed with your input.

How we will do it Mid 2009

COMMUNITY ENGAGEMENT

In recent times, there has been a high level of public

awareness and debate surrounding proposals to develop

new water sources. In addition, the community is helping to

secure our water future by learning to use water wisely and

adapting to a drier climate.

Water Forever will continue to shape our water future, with

input from the community. The focus is on listening to the

needs of the community and stakeholders, encouraging

involvement, sharing information on options for our future

and understanding different viewpoints.

Anyone can “Get involved.” You can register your interest at

any time during the 5 stages of the project.

We are currently in the “Have your say” stage. We welcome

your input to issues raised in this Options Paper. There are

lots of different ways you can become involved.

With your help, we can ensure water for all, forever.

WATER FUTURES

Creating a water future for the study area for the next 50

years requires us to develop a shared understanding of

the planning context, water availability and projections

for population growth and water demand. This work is

underpinned by robust science and consideration of the

potential impacts of a diverse range of trends and possible

future scenarios.

OPTIONS FOR OUR WATER FUTURE

This section provides information on trends and planning

assumptions that provide a framework for Water Forever.

WATER FOR LIFE

In December 2003 the United Nations (UN) proclaimed the

years 2005 to 2015 as the ‘International Decade for Action:

Water for Life.’

The UN noted that:

“Water is crucial for sustainable development including the

preservation of our natural environment and the alleviation

of poverty and hunger. Water is indispensable for human

health and well-being.”

Water is an essential part of the environment and

water services are essential for economic development.

Water services are needed by all businesses and other

organisations, like schools and hospitals. Recreational

spaces such as ovals and parks also need water and provide

important urban amenity.

Importantly, water has cultural heritage and spiritual value to

both Indigenous and non-Indigenous Western Australians.

Although the drought in some parts of the country means

that water restrictions have been imposed on water use for

gardens and other non-essential water using activities, most

people living in Australian cities have access to reliable and

high quality drinking water for their daily needs.

Similarly, cities in Australia are well serviced by sewerage

systems that remove and treat wastewater from homes

and businesses. Wastewater treatment makes a signifi cant

contribution to public health.

Flood management and drainage standards have helped

to manage fl ooding, curtailed the spread of disease and

enabled urban development.

The Water Corporation recognises the importance of

reliable and safe water, wastewater and drainage services to

meet the needs of customers and to protect public health.

The Water Corporation and other government policies

and guidelines refl ect the importance we place on water

quality. These policies and guidelines are consistent with the

Australian Drinking Water Guidelines.

The Water Corporation has an operating licence, issued by

the Economic Regulation Authority that requires certain

standards to be met when delivering drinking water,

wastewater and drainage services. The Water Corporation

has a Customer Charter, which forms a part of this licence.

Water Forever will continue to ensure that water is available

to meet the essential water needs of the community, and in

doing so, protect public health.

CLIMATE CHANGE AND VARIABILITY

Climate change and global warming are terms used to

describe the climatic changes that result from the enhanced

greenhouse effect. This effect is the excessive trapping

of heat in the Earth’s atmosphere caused by increased

greenhouse gas emissions associated with burning fossil

fuels, agriculture and land clearing.

The impact of climate change will vary in different regions

but may include:

• higher average air temperatures;

• changed rainfall patterns; and

• rising sea levels.

Climate variability recognises that many of these trends

will fl uctuate from year to year, for example there may be

some wet years and some very dry years. Learning to adapt

to these extremes is part of the challenge facing the Water

Corporation and the Western Australian community.

Global research

The International Panel on Climate Change has produced

numerous reports detailing the latest scientifi c, technical and

socio-economic research conducted to better understand

the risk of human-induced climate change, its observed and

projected impacts and options for adaptation and mitigation.

The latest report concludes that it is very likely that over the

past 50 years cold days, cold nights and frosts have become

less frequent over most land areas. Hot days and hot nights

have become more frequent. The report also found that it is

likely that in most land areas heat waves and heavy rainfall

periods have become more frequent.

With reference to water resources, the report concludes that

there is high confi dence that by the mid-21st century annual

river runoff and water availability will decrease in some dry

regions, including many regions in Australia.

11

2010

2007

2004

2001

1998

1995

1992

1989

1986

1983

1980

1977

1974

1971

1968

1965

1962

1959

1956

1953

1950

1947

1944

1941

1938

1935

1932

1929

1926

1923

1920

1917

1914

1911

Total Annual* Inflow

(GL) to Perth D

ams**

Annual Total 1911–1979 average (378 GL)

* a year is taken as May to April ** 2004/05 inflow to 31 Jan 2005

1980–1999 average (232 GL)

38% Less

70% Less

2001–2007 average (105 GL)

1000

900

800

700

600

500

400

300

200

100

0

YEARLY INFLOW TO PERTH DAMS INCLUDING SOUTHERN SOURCES

In 2007, the government of the United Kingdom

commissioned a report on the economics of climate change.

The report outlined a range of economic impacts that may

result from climate change including:

• extreme weather could reduce global gross domestic

product (GDP) by up to 1%;

• a two to three degrees Celsius rise in temperatures could

reduce global economic output by 3%;

• if temperatures rise by fi ve degrees Celsius, up to 10%

of global output could be lost (the poorest countries

would lose more than 10% of their output); and

• in the worst case scenario, global consumption (per

head) would fall by 20%.

Australian research and response

Rainfall decline around Australia has occurred in areas of

high population and higher economic activity (including

Perth and the study area), which poses signifi cant challenges

to meet growing demand for water in a timely fashion.

The CSIRO and the Bureau of Meteorology recently released

a report, Climate Change in Australia, which provides

essential tools for government, industry and the community

to understand the likely magnitude of climate change in

Australia and the possible impacts.

This report concludes that the 15% decrease in rainfall

in South Western Australia over the past 30 years is likely

to be at least partly due to human induced increases in

greenhouse gases. The future projection for Perth is for

further decline in winter and spring rainfalls that are vital

for streamfl ows to public water supply dams as well as our

natural environment.

South West of Western Australia

Reduced rainfall in the South West of Western Australia has

resulted in fl ows to public water supply dams decreasing by

70% since the mid - 1970s.

12

OPTIONS FOR OUR WATER FUTURE

The most severe projections by CSIRO are for average annual

rainfalls to decline in the South West by 20% by 2030 and

60% by 2070, from the standard period used to forecast

streamfl ows. This is based on a high emissions scenario.

However, it is worth noting that CSIRO climate change

modelling suggests that some rainfall activity will be more

intense and this may increase fl ood risk.

Research conducted by the Indian Ocean Climate Initiative

(IOCI) has found that in the South West:

• average temperatures have increased by 0.8 degrees

Celsius since 1910 with most change occurring over the

past 50 years;

• average Indian Ocean surface temperatures have

increased by 0.6 degrees Celsius;

• over the past 35 years, the number of storms have

decreased, bringing less rain; and

• over this same period, annual rainfalls have decreased

by up to 10% and winter rainfalls have decreased by up

to 15%.

The Department of Water is currently using the IOCI data to

determine sub-regional climate scenarios for the Perth-Peel

Regional Water Plan.

Security through Diversity

Until the 1970s, Perth relied mainly on surface water sources

- dams built in the hills. Over the past 30 years, signifi cant

groundwater resources have been developed. Groundwater

represents up to 60% of all water currently sourced for the

IWSS water grid.

Reduced infl ows into our dams have resulted in lower

surface water availability. Climate change has also decreased

recharge to groundwater in some areas.

In 2004, the Water Corporation developed the Security

through Diversity strategy to diversify from these traditional

water sources. Most recent innovations include more rainfall

independent sources such as desalination, water recycling and

water use effi ciency. Innovations have been made in catchment

management and water trading.

Water Forever will look at how these and other sources can

continue to play a role in our water future.

WATER

Water availability

The State Water Plan 2007 noted that there is about 1,937

gigalitres of water available in the Perth groundwater basin

and 1,610 gigalitres of surface water in the South West. Of

this only about 30% is still available for development - the

balance is either reserved for the environment or already

allocated for use. Many of these resources are a long way

from Perth and many are also relatively small and not

suitable for development for public water supply.

The Department of Water is updating these regional

assessments of surface and groundwater availability as part of

the Perth-Peel Regional Water Plan. This will involve estimates

of available average annual surface water and groundwater

resources forecast to 2030. As part of this work they are

considering the impact of reduced rainfall projections.

In addition, the Department of Water is currently fi nalising

a study that provides more information about the potential

volume of drainage water that may be available for recycling

across the Swan Coastal Plain. Other work being undertaken

includes the preparation of maps that will provide more

information about the availability of water for garden bores.

The Water Corporation will incorporate the fi ndings of these

studies, as they become available.

Water Forever will be developed in the context of

understanding the availability of all water resources,

including the need to retain water in the environment and

share water resources with other sectors.

13

Nature of water use

Agriculture is the largest water-using sector on a global

scale, consuming almost two - thirds of water drawn

from rivers, lakes and groundwater. Whilst this is the case,

irrigation has improved the productivity of agriculture.

Since 1960, world water use for crop irrigation has risen by

over 60% and current use is predicted to double by 2050 as

agriculture becomes an energy supplier for biofuels and feed

stocks.

These global trends were consistent with the ‘Australian

Water Resources Assessment (2005)’ that indicated that

agriculture uses 65% of all water in Australia. The next two

largest water-using sectors were households (11.2%) and

public water supply (11.1%). Water for public water supply

includes water used for fi refi ghting, wastewater treatment

plant operations and water lost through leakage.

In metropolitan areas however, there is less water supplied

to agriculture and mining and more water used by industry,

households and in the service sector (hospitals, schools,

government agencies).

The Department of Water forecasts 645 gigalitres of total

water use by all sectors in 2008. The Water Corporation will

access about 40% of this for public water supply.

The IWSS water grid supplies water to people in Perth

(85%), Goldfi elds and Agricultural region (10%) and

Mandurah and towns in the South West (5%). Most water is

used by households.

Water used outdoors and in laundries and toilets does not

have to be of drinking water quality. Water Forever will

explore the best fi t for purpose options (where water is

treated to a standard suitable for its end use) and ways to

achieve greater water savings.

Business and industry use approximately 21% of all public

water supply. About 5% of metropolitan businesses use

70% of all business water demand.

The Water Corporation targets high water using businesses

(those that use more than 20,000 kilolitres a year) through

its Waterwise Business Program. These businesses generally

include heavy industry, brewers, laundries, offi ce buildings,

major hotels, food manufacturers, universities, shopping

centres and hospitals. To date 209 businesses have

participated in the program.

Water Forever will identify further opportunities to increase

water recycling and water use effi ciency in business and

industry.

Sourcing water for use

The amount of water available for the IWSS water grid

is known as the water yield. The yield of existing water

supplies is somewhat uncertain due to:

• reduced infl ows to dams;

• the potential requirement to increase fl ows from surface

and groundwater resources to the environment; and

• increasing and competing land uses within

water supply catchments rendering them unsuitable for

use or requiring higher levels of treatment.

Streamfl ows over the last 30 years averaged 163 gigalitres

a year. In this period, there were some wet years early

on. Over the past six years, when rainfall was the lowest

on record, streamfl ows into our dams were only half this

amount.

Groundwater availability is also being reduced because of

declining rainfall.

2008 FORECAST PUBLIC WATER SUPPLY USE IN THE STUDY AREA (GIGALITRES)

Residential (bathroom) - 36 Residential (outdoors) - 94

Residential (laundry) - 28

Business - 60

Residential (kitchen) - 18

Residential (toilets) - 24Firefighting, leakage, wastewater treatment - 25

14

OPTIONS FOR OUR WATER FUTURE

The existing IWSS water yield is estimated to average 315

gigalitres a year to 2020, based on the low rainfall period

from April 2001 to May 2007.

This fi gure includes water from both the Perth and Southern

Seawater Desalination Plants and also includes the water

available from trading with the Harvey Water irrigation

cooperative. This water yield is based upon a probability of a

total outside sprinkler ban occurring once in fi fty years.

Based on work undertaken by CSIRO and IOCI, climate

change is expected to result in reduced rainfall in the Perth-

Mandurah area. This will adversely impact yields from both

surface water and groundwater sources.

In particular, surface water yields (including water from

trading with irrigation) will be most severely impacted. By

2060, the most extreme projection is for a 60% decrease in

rainfall, which would virtually eliminate water from dams as

a reliable water source in most years, due to evaporation.

CSIRO projected (under a median emissions scenario), that

by 2030 rainfall could decrease by 20% from 1980 to

1999 averages. Given that we have already experienced a

12% reduction in rainfall since this time, a further 8% loss

in rainfall is estimated to reduce streamfl ows by a further

20 gigalitres by 2030. This may also further reduce water

availability from groundwater resources.

This scenario projects a further 20% reduction in rainfall by

2060, resulting in greater loss of surface and groundwater

supply.

Climate science is evolving and these projections are based

on probabilities. However, it is important to understand the

potential impact of reductions in rainfall on public water

supply during this period of rapid change.

Decisions to accelerate water conservation initiatives or

invest in new supply capacity will be made incrementally.

There is an opportunity for us to progressively adapt as our

knowledge of climate and experience of rainfall unfolds.

Planning supports sustainable decisions by making the

impact of different scenarios transparent. Engaging with the

community allows us to evaluate a range of responses to

these possible futures.

The Department of Water determines the amount of water

required to sustain the ecological, social and economic

values of water resources. Retaining water for these reasons

is important, but can reduce the amount of water available

for other uses, such as public water supply.

Environmental water provisions are currently being reviewed

for a number of surface and groundwater sources in

the metropolitan area. No allowance has been made in

the above fi gures for reduced surface water availability

as a result of regulatory requirements for increased

environmental water provision.

POSSIBLE WATER YIELDS FOR THE IWSS WATER GRID TO 2060

Possible IWSS water yield,

without further investment

Desalination

sources

Surface water

sources

Groundwater

sources

IWSS system yield

Gigalitres a year

Actual water yield 2007 18 101 157 276

Possible water yield by

2020

95 100 120 315

Possible water yield by

2030

95 80 110 285

Possible water yield by

2060

95 20 100 215

15

Population forecasts

In 1950, the population of Perth was around 400,000 and has

grown at an average of 22,500 people each year since then.

By 2007, approximately 1.6 million people (76% of Western

Australia’s population of 2.1 million people) were living

in the Perth-Mandurah area. The population is currently

growing by approximately 27,000 people each year.

The Western Australian Planning Commission forecasts

population growth for the state. The most recent population

forecasts were updated in November 2005 with the release

of ‘Western Australia Tomorrow - Population Projections for

Planning Regions 2004 – 2031 and Local Government Areas

2004 - 2021.’ This report included population projections

through to 2031.

In summary, these forecasts suggest that the annual increase

in population has peaked at about 27,000 a year and will

now slow to 23,000 new people each year between 2021

and 2031. The Water Corporation is basing water demand

projections on these forecasts through to 2030.

Water Forever has assumed population growth of 20,000 a

year from 2031 – 2060, in keeping with forecast trends for a

decline in the rate of growth after this time.

Water Forever is planning for a forecast population of 2.8

million people by 2060. If this growth is achieved sooner

than expected, water infrastructure delivery, which includes

the development of new water sources and the expansion

of wastewater treatment systems, can be brought forward.

Similarly, delivery can be pushed back if there is a signifi cant

reduction in growth rates.

Water demand forecasts

A number of external factors infl uence water demand

including:

• population size and growth;

• average household size;

• rainfall patterns;

• incidence of very hot days;

• business activity; and

• the availability of alternative water sources such as

garden bores and rainwater tanks.

Water Forever is basing water demand on the major factor

of population growth.

Residential demand is calculated by assuming that customers

manage to reduce Perth household water use to 100

kilolitres of water a year, a target set in the State Water Plan

2007. This is a decrease in current household water use,

which has averaged 107 kilolitres a year over the past 6

years. Of this water, about half is used outside the home.

Other demands include water supplied by the IWSS water

grid for use by business, industry, services such as hospitals

and schools, fi re fi ghting and water losses through leakage.

This demand has averaged 47 kilolitres a year over the

past 6 years. Combined with household water use, water

consumption per person averages 153 kilolitres a year.

These demand assumptions refl ect recent use and highlight

the signifi cant gains made in water use effi ciency over the

past 10 years. This represents a reduction in overall water

demand of approximately 17% since the peak demand of

185 kilolitres a year in 2000/01.

FORECAST POPULATION GROWTH IN THE PERTH-MANDURAH REGION 2007-2060

Forecast population growth 2007 2020 2030 2060

Population 1,600,000 1,950,000 2,200,000 2,800,000

Average annual growth

(number of people)

27,000 26,000 23,000 20,000

Average annual growth

(%)

1.8% 1.4% 1.1% 0.7%

16

OPTIONS FOR OUR WATER FUTURE

FORECAST WATER DEMAND 2007 - 2060

Forecast

water demand

2007 2020 2030 2060

Gigalitres a year

Perth - Mandurah

population forecast

1,600,000 1,950,000 2,200,000 2,800,000

Perth demand 235 265 294 370

Mandurah demand 13 23 30 48

Goldfi elds and Agricultural

demand

28 32 36 52

Total estimated water

demand

276 320 360 470

17

AVERAGE WATER DEMAND FOR RESIDENTIAL AND OTHER USES

Perth water demand

(kilolitres per person a year)

Average use

(1995 - 2001)

Average use

(2002 - 2007)

Average use

(forecast)

Residential (Household) 120 107 100

Other 56 46 45

Total water demand 176 153 145

These forecasts demonstrate a commitment to meet the

target to reduce residential water use to 100 kilolitres a

person for people in Perth, as outlined in the State Water

Plan 2007. This saving will require continued and additional

investment in water use effi ciency initiatives.

They do not include additional water supply to meet Perth

and Mandurah industrial demand, which is predominantly met

through self-supply groundwater, water recycling and trading.

Note that these demand forecasts could be signifi cantly

impacted by the factors outlined above. Further analysis

will be conducted to investigate the sensitivity of these

projections to impacts of household size, hot days, urban

density and other considerations.

WASTEWATER

Wastewater fl ows from Perth and Mandurah

In 2007 the Water Corporation treated 120 gigalitres

(328 megalitres a day) of wastewater in metropolitan

wastewater treatment plants. This means that about 44%

of all water supplied to customers from the IWSS water

grid is fed back into the Water Corporation’s wastewater

systems. Hence, the amount of wastewater that enters the

system is dependent on the amount of water consumed by

households, business and industry.

Wastewater comes from:

• homes (65%); and

• business and service industries (35%).

Businesses are a mix of commercial premises such as shops

and offi ces, as well as industrial premises. Commercial

premises produce smaller amounts of wastewater, similar

in nature to residential wastewater. Industrial wastewater is

closely monitored by the Water Corporation to ensure toxic

compounds do not enter the wastewater system.

Future wastewater fl ows

Based on the forecasts for population growth and water

demand, annual wastewater fl ows for Perth and Mandurah

are forecast to be:

• by 2020,155 gigalitres (426 megalitres a day);

• by 2030, 179 gigalitres (490 megalitres a day); and

• by 2060, 237 gigalitres (650 megalitres a day).

These projections refl ect an increase in the proportion of

residential and commercial areas sewered due to new land

development almost exclusively occuring in sewered areas.

These forecasts are dependent on a number of factors

including:

• in home and commercial water demand;

• number of properties connected to the Water

Corporation’s wastewater system;

• the reduction in fl ows due to in home and business

water use effi ciency; and

• the location and density of population increases.

2060

2050

2040

2030

2020

2010

2000

1990

1980

0

100

200

300

400

500

600

700

800

FORECAST WASTEWATER FLOWS (MEGALITRES PER DAY)

Projected FlowsHistorical Flows

18

FUTURE RECYCLING OPPORTUNITIES FROM MAJOR WASTEWATER TREATMENTS PLANTS IN THE PERTH-MANDURAH REGION

Wastewater

Treatment Plants

Recycling in

2008

Possible

recycling by

2020

Possible

recycling by

2030

Possible

recycling by

2060

Nature of recycling

Gigalitres a year

Alkimos 0 4 6 13 Horticulture (seasonal)

Industry

Beenyup 0.8 25 40 50 Groundwater

replenishment

Subiaco 0.7 2 3 20 Public open space

Groundwater

replenishment - 2030

Woodman Point 4.3 10 20 60 Industry

Groundwater

replenishment - 2030

East Rockingham 1.2 2 2 10 Industry

Groundwater

replenishment - 2030

Mandurah

(combined)

0.3 1 2 5 Industry

Public open space

Forecast recycling 7.3 44 73 158

Total fl ows 120 155 179 237

Recycling % 6% 28% 41% 67%

OPTIONS FOR OUR WATER FUTURE

Western Australian Planning Commission forecasts provide

the basis for the population projections used. In addition,

they provide information on the expected distribution and

density of people in the greater Perth and Mandurah areas.

These population forecasts have infl uenced Water Corporation

decisions to increase capacity at existing wastewater treatment

plants and invest in new treatment plants.

Need to increase wastewater system capacity

The total amount of wastewater than can be treated by

the current system is 123 gigalitres a year. Currently, total

wastewater fl ows in the Perth - Mandurah region are 120

gigalitres a year. This means that the existing wastewater

treatment system is nearing capacity.

By 2060, fl ows are estimated to be in the order of 237

gigalitres a year. This is nearly double the current fl ows.

The existing wastewater treatment system will need to

be substantially upgraded and new systems built to cater

for the increased fl ows. Options for future expansions are

discussed in the Create section.

19

Wastewater recycling forecasts

Currently, the Water Corporation is recycling about 12.5% of all

treated wastewater statewide. In Perth, about 6.1% is recycled.

Through continued investment in water recycling, we have

the capacity to double this amount by 2012, demonstrating

substantial progress towards the 20% target set in the

State Water Strategy in 2003. The State Water Plan 2007

established a long-term target to recycle more than 30% of

all treated wastewater.

It is possible that the volumes of wastewater recycled could

increase even further, particularly if a large scale scheme

such as groundwater replenishment is adopted as a water

source option.

DRAINAGE

Increasingly, drainage water is being used locally in urban

developments by applying the principles of water sensitive

urban design. The Department of Water is responsible

for planning for the major drainage systems in Western

Australia and the preparation of Drainage and Water

Management Plans (DWMP).

The State Water Plan 2007 identifi ed a number of districts

that require a DWMP due to proposed land development.

The Water Corporation has drainage infrastructure in a

number of these catchments.

It is not anticipated that the Water Corporation’s drainage

network will expand. New drainage works are expected to

be the responsibility of Local Government; in keeping with

the approach for drainage water to be retained for local use

or environmental fl ows where possible.

To fi nd out more about the areas covered by DWMPs and

how drainage works, refer to the Connect section.

20

CONSERVE

Supplying water to meet the needs of communities is

inextricably linked to the water cycle. The Water Corporation

works to conserve the natural environment and minimise

the impact of infrastructure delivery required to provide

essential services.

We recognise the cultural values associated with water, in

particular the importance of water to Indigenous communities.

However there are challenges. The South West of the state, a

global biodiversity hot-spot, will be impacted by climate change.

Above all, we know that the drying climate means it is

imperative for us to use all water wisely. We need to use

less, recycle more and use water that is fi t for purpose.

This section provides more information on our programs to

conserve water, the environment, energy, biodiversity and

cultural heritage.

WATER USE EFFICIENCY

The Water Corporation works closely with customers to reduce

demand for drinking water supplied from the IWSS water

grid. When we reduce demand for this water, we reduce the

amount of wastewater produced by households and businesses

requiring treatment, recycling and discharge. We also reduce

the amount of energy used to supply and treat water and

wastewater, thereby reducing greenhouse gas emissions.

Our approach to water use effi ciency targets a number of

areas, including:

• improving the effi ciency of water supply infrastructure by

reducing water pressure and leaks;

• supporting the introduction of legislative changes to

building codes and water use effi ciency labelling on

water-using products;

• replacing the use of drinking water for non-drinking

purposes (such as garden watering) with alternative

sources of water;

• encouraging research and development into water

effi cient technologies;

• supporting the Waterwise Rebate Program to replace

ineffi cient water using appliances with more effi cient

products;

• administering the introduction of permanent Water

Effi ciency Measures;

• development of Waterwise Programs which include

training and accreditation in water use effi ciency

best practice for garden centres, irrigators, plumbers and

developers; and

• community education including the use of advertising

and behavioural change initiatives such as social

marketing and comparative billing.

Over the past 20 years the Water Corporation has actively

pursued the development and implementation of Waterwise

Programs to reduce water demand in households and

businesses. These programs are recognised nationally and are

now being adopted by a number of other states in Australia.

We are committed to continuing to expand, enhance and

maintain community partnerships to educate and provide

tools to improve water knowledge and water use effi ciency

through Waterwise Programs.

Increasing water use effi ciency is important to ensure water

for all, forever.

PERMANENT WATER EFFICIENCY MEASURES

Water restrictions have been used to manage demand from

the IWSS water grid in times of severe shortage caused by

drought or, more recently, our drying climate. They target

non-essential uses of water (such as water for gardens) to

conserve drinking water supplies for essential uses.

In other States, the most recent drought has resulted in the

imposition of water restrictions of varying levels, ranging

from sprinkler bans to no watering of lawns and very limited

water use on gardens.

The Water Corporation sees such extreme water restrictions

as undesirable. Severe water restrictions, such as banning

outdoor sprinkler use, adversely impact the community both

in terms of dependent industries (horticulture, recreation) and

homeowners through the loss of gardens and green space.

Since 2001 we have introduced measures that save

water and maintain gardens by working closely with the

community and associated industries. One example is

the two day a week sprinkler roster in Perth which saves

approximately 45 gigalitres of water a year. This is enough to

supply 188,000 households and helps to avoid over 30,000

tonnes of CO2-equivalent greenhouse gas emissions.

In October 2007, this sprinkler roster system, together with

other Water Effi ciency Measures, became permanent for

the Southern part of Western Australia. Our customers

overwhelmingly support the introduction of this sprinkler

rostering system as a permanent part of how we use water

sensibly in Western Australia.

Other water saving measures suited to hotter average

temperatures in the Northern half of the State have also

been introduced.

Permanent water effi ciency measures make a substantial

contribution to conserving water and our natural environment.

22

OPTIONS FOR OUR WATER FUTURE

WATER IN THE NATURAL ENVIRONMENT

The Water Corporation’s services are a major part of the

water cycle, which is intrinsically linked to environmental

health. In taking water from the environment and returning

drainage and treated wastewater we aim to sustain the

environment, now and in the future. We protect ecological

processes in a number of ways, including:

• monitoring the environments we take water from to

ensure water dependent ecosystems are not signifi cantly

affected;

• reducing the amount we take from the environment

through water effi ciency initiatives;

• recycling water and wastewater;

• minimising our infrastructure footprint;

• reducing discharges where appropriate;

• providing water for the environment; and

• reducing energy use.

The environment is a key issue we consider when planning for

new water sources and wastewater and drainage services. Of

particular importance are the environmentally sensitive areas

protected under the Environmental Protection (Environmentally

Sensitive Areas) Notice 2005. They include important wetlands

and ecological communities, natural and world heritage sites,

rare fl ora and fauna, and Bush Forever sites.

As part of the Perth-Peel Regional Water Plan, the

Department of Water is reviewing environmental water

requirements across the region and will develop a program

to identify priority requirements where they have not

yet been completed. The Perth-Peel Regional Water Plan

will consider environmental water provisions for water

dependent ecosystems. These provisions take into account

the amount of water required to sustain ecological, social,

economic and other values associated with water resources.

Water Forever will refl ect the need to retain water in the

environment for these reasons.

ENVIRONMENTAL IMPROVEMENT AND MANAGEMENT

We are strengthening our ability to manage impacts through

the development of an Environmental Management System,

which will have national accreditation. The Environmental

Management System supports commitments made in our

Environmental Policy which include:

• to sustain Western Australia’s water resources;

• to comply with environmental regulations;

• to prevent pollution; and

• to continually improve the way we do things, including

conserving natural resources and ecological processes.

The System provides a robust framework for identifying

and managing environmental risks associated with water

source development, wastewater discharges and recycling,

construction and operations. This includes developing,

implementing, monitoring and reviewing environmental

objectives and actions.

WATER IN THE BUILT ENVIRONMENT

Water in our homes

Most of the water used in residential and commercial

buildings in the study area is of drinking water quality

supplied through the IWSS water grid. This water is moved

from various sources (including dams, groundwater,

and desalination) to homes and businesses. There is an

opportunity to make greater use of the rain that falls on

these buildings to supply water for non-drinking uses.

Most homes in Perth direct the water that drains off their

roof into soak wells to replenish groundwater. About

150,000 homes access this source through garden bores to

water their gardens. The sustainable use of garden bores is

a good fi t for purpose use of water collected at source. The

permanent Water Effi ciency Measures will help to ensure

that these groundwater resources are used responsibly and

not unnecessarily depleted.

Some homeowners have installed rainwater tanks to collect

water from the roof for various uses including garden

watering, car washing, toilet fl ushing and clothes washing.

Other homeowners are using greywater from bathrooms

and laundries for garden irrigation.

23

The State Government supports the use of alternative water

supplies, such as rainwater tanks and greywater systems

through the introduction of changes to building codes

known as Five Star Plus. In the second stage of this program,

proposed for introduction later in 2008, new residential

and commercial buildings will require separate plumbing

to be installed that will allow for ease of connection to an

alternative water supply for non-drinking water uses like

toilet fl ushing.

Water in our businesses

Waterwise Businesses are also making changes towards

better water use effi ciency.

The fi rst fi ve Green Star Green Building Council of Australia

offi ce in Western Australia is being built at 140 William

Street, Perth. The sustainable design features in the

building focus on energy, water use effi ciency and waste

management. The building is expected to be completed by

the end of 2009.

By the end of October 2007, 37 commercial buildings across

Australia had been Green Star certifi ed with a further 380

registered for certifi cation. One of these buildings is the

Council House 2 in Melbourne, which has been awarded six

Green Stars and won a United Nations Award, demonstrating

outstanding leadership in sustainable building design.

There is further scope for new commercial building design in

Perth to adopt the principles of the Green Star rating system.

Water for public open space

Many of our parks and ovals are watered using groundwater

(from bores), which has been recharged through rainfall.

This is also a good example of water being collected and

used at is origin, meaning fewer resources are consumed to

treat and supply the water.

Some new land developments feature artifi cial lakes

or wetlands in public open space areas, which collect

stormwater and fi lter it before it recharges groundwater.

This is a principle of water sensitive urban design, to

integrate urban planning with the management, protection

and conservation of the urban water cycle.

There are a number of requirements under the National

Water Initiative with respect to water sensitive urban design,

water sensitive urban developments and integrated urban

water management. State and Local Government initiatives

are progressing work in this area, with the assistance of the

Water Corporation.

The State Government encourages alternative water

supplies for public open space in new developments. There

are opportunities to use shallow groundwater for non-

drinking water uses, inject recycled water into groundwater

to increase water levels, and increase the use of rainwater

tanks, garden bores, sewer mining and greywater recycling.

The fi rst trial of an alternative water supply scheme

commenced at Brighton in Perth’s Northern suburbs.

A community bore scheme supplies groundwater to

households for gardens and public open space. This

scheme is estimated to save 71 kilolitres of water a year per

household from the IWSS water grid.

Another similar non-drinking water scheme under

development is the Wungong Urban Water Project, which

has Commonwealth funding and is projected to save about

2 gigalitres of scheme water a year.

ENERGY EFFICIENCY

Energy use

Energy use in water and wastewater management is linked

to climate change at a global scale. A number of National

and Western Australian initiatives are being undertaken to

help to manage energy across the community, as part of

global efforts to reduce the forecasts for global warming:

• the National Framework for Energy Effi ciency has been

developed with the aim of achieving a major

enhancement of energy effi ciency performance, reducing

energy demand and lowering greenhouse gas emissions;

• the Commonwealth ‘Energy Effi ciency Opportunities

Act 2006’ has been enacted to mandate the assessment,

monitoring and reporting on energy use and energy

effi ciency actions; and

• a mandatory Energy Effi ciency Program has been

developed in Western Australia to work with industry to

develop a mandatory energy effi ciency scheme applicable

to large and medium sized power consumers. The Water

Corporation is working collaboratively on this initiative.

In 2006/07 the Water Corporation used 1.6 million

gigajoules of energy in the following areas:

• 90% from electricity;

• 8% for transport; and

• 2% for heating using natural gas and biogas.

24

OPTIONS FOR OUR WATER FUTURE 25

LOCATIONS OF ENVIRONMENTALLY SENSITIVE AREAS AS DEFINED UNDER THE ENVIRONMENTAL PROTECTION ACT 1986

The Water Corporation’s energy consumption is directly

related to three major factors:

• number of customers;

• level of water or wastewater treatment required - the

higher the quality of water and wastewater required, the

more energy used to treat it; and

• the distance over which water and wastewater is

transported.

Almost 70% of all energy use is attributed to water services

with a further 20% due to wastewater services. Support

activities such as energy use in buildings and transport

account for the balance.

New rainfall independent sources tend to use more energy

as they often require higher levels of treatment. The energy

needed to treat 1 kilolitre of drinking water varies by source:

• 0.4 to 0.6kWh for water treatment of surface and

groundwater sources;

• 0.8 to 1.0kWh for recycled water; and

• 3 to 5kWh for reverse osmosis desalination of seawater.

Relationship to household energy use

In Perth, the average household used 276 kilolitres of

water in 2006/07. This required 370kWh of electricity for

treatment and about the same amount to transport the

water. The same home used an average of 6,500kWh of

electricity in the same year.

Therefore, the energy associated with water use in a home

represents approximately 6% of the total household energy

use (not including transport). When you include the energy

associated with transporting water and wastewater around

the system, the total increases to 12%.

The greater uptake of on site water supply and wastewater

recycling systems such as rainwater tanks and greywater

systems may reduce the average energy use associated with

water consumption in households. This issue requires further

research and needs to take into account energy consumed

to manufacture on site water storage systems (such as

rainwater tanks) and the transportation of these to homes.

Reducing energy use

The Water Corporation has registered to take part in

the Federal Government Energy Effi ciency Opportunities

Program. This program aims to improve the identifi cation

and evaluation of energy effi ciency opportunities for large

energy consuming businesses.

Participating businesses identify, evaluate and report publicly

on cost effective energy savings opportunities. As part of

the program the Water Corporation is undertaking energy

assessments of approximately 60 sites by June 2011.

Greenhouse strategy

In 2006/07 the Water Corporation accounted for more than

419,000 tonnes of CO2 equivalent emissions.

AMOUNT OF ENERGY USED IN A YEAR TO DELIVER WATER AND WASTEWATER SERVICES

Assets Gigajoules a year Percentage

Water sources 455,390 28.3%

Water treatment 180,821 11.3%

Water conveyance 478,539 29.8%

Wastewater conveyance 92,766 5.8%

Wastewater treatment 236,690 14.7%

Buildings and depots 33,143 2.1%

Transport 129,434 8.0%

TOTAL 1,606,783 100%

26

Drainage & Irrigation - 0.1

Buildings & Depots - 9.0 Transport - 13.1

Wastewater Pumping Stations - 22.0

Wastewater TreatmentPlants - 87.3

Water Pumping Stations - 138.9

Bores - 78.8Water Treatment Plants - 54.7

Water (Other) - 15.3

SOURCE OF CO2 EMISSIONS (KILOTONNES OF CO2-e) IN 2006/07 FROM WATER AND WASTEWATER SERVICES

OPTIONS FOR OUR WATER FUTURE

Since 2001, the Water Corporation has implemented a

number of greenhouse gas initiatives:

• supporting renewable energy generators. The

Perth Seawater Desalination Plant uses state-of-the-art

energy effi ciency technology and purchases power from

the Emu Downs Wind Farm near Cervantes;

• reducing the demand for water through water use

effi ciency initiatives;

• planting trees to sequester carbon;

• improving vehicle fl eet effi ciencies; and

• using biogas from wastewater treatment processes.

The Water Corporation has set an aspirational target to

have zero net greenhouse gas emissions by 2030 and is

implementing a strategy to achieve this. Areas of focus

include:

• improving energy effi ciency;

• supporting renewable energy generators;

and

• managing emissions produced from wastewater treatment.

Investing in renewable energy has the greatest potential

to reduce emissions. The Water Corporation is well placed

to invest in a range of renewable energy sources including

ocean waves, hydro-electricity, biogas, wind and solar energy.

Most electricity used by the Water Corporation is purchased.

Approximately 1.5% is generated at the Woodman Point

Wastewater Treatment Plant from biogas.

Almost 20% of our energy is purchased from generators of

renewable energy, which includes wind, landfi ll gas, and the

use of biogas. This is expected to increase to over 35% in

2008 with the Perth Seawater Desalination Plant operating

at full capacity using electricity purchased from the Emu

Downs Wind Farm. In addition, the Water Corporation

is committed to securing renewable energy to satisfy the

energy requirements of the Southern Seawater

Desalination Plant.

BIODIVERSITY

The Water Corporation manages about one million hectares

of land in the State. About half of this is in the South West

ecoregion, recognised as one of only 34 biodiversity hot-

spots in the world, and the only one in Australia.

Biodiversity is the abundance and diversity of living things

and the ecosystems they belong to, on land and in water.

Biodiversity is crucial to healthy ecosystem function, which

helps to maintain water quality. The State’s biodiversity is

under threat from climate change, land clearing, introduced

pests and diseases, salinity and fi re.

Most catchment areas, water reserves, wastewater

treatment plants and land reserved for future water or

wastewater infrastructure have large tracts of native

vegetation and sometimes water bodies such as wetlands.

They contribute to the retention of biodiversity. Water

Corporation owned land can also provide important

ecological linkages between parcels of bushland to facilitate

movement of fl ora and fauna.

The Water Corporation’s activities can also affect

biodiversity, through the management of land, infrastructure

development, drainage and discharge of water and

wastewater to the environment.

We try to continually improve and manage the land under our

care and where practical, restore or improve biodiversity. This

includes minimising land clearing and severing of ecological

linkages, managing pests and diseases, minimising impacts of

operations on biodiversity and working with universities and

research institutions to learn more about our environment.

Biodiversity is a key issue considered in the development of

future water sources and the delivery of wastewater and

drainage services.

27

28

BUSH FOREVER SITES IN THE PERTH - MANDURAH REGION

OPTIONS FOR OUR WATER FUTURE 29

SITES OF HIGH IMPORTANCE TO BIODIVERSITY IN THE PERTH - MANDURAH REGION

CULTURAL HERITAGE

The Heritage Council of Western Australia defi nes cultural

heritage as including:

“Places and events which defi ne and sustain the Australian

character to provide a living and accessible record of the

nation’s cultural history. It comprises places, objects, events,

cultural practices, stories, records and intangible values

which refl ect Australia’s biophysical diversity and its cultural

diversity - Indigenous and non-Indigenous.”

When planning for new water, wastewater and drainage

services we consider heritage, and in particular, Aboriginal

cultural heritage.

Aboriginal cultural heritage

Several years ago the Water Corporation formed a specialised

Indigenous Resources Group to provide a centre of expertise

for Indigenous matters, particularly those related to Native

Title and Heritage Management. To underpin this group

a Statement of Commitment to Indigenous people and

communities has been developed with a commitment to:

• consult with Indigenous groups and communities to

promote an understanding of each other’s concerns and

aspirations;

• assist Indigenous groups to manage issues and

challenges they face as a result of our activities;

• identify and support partnering opportunities that make

a positive difference to Indigenous communities; and

• learn and work with Indigenous people to achieve

sustainable management of water.

Non-Indigenous cultural heritage

There are numerous pipelines; pump stations and other

infrastructure owned by the Water Corporation that have

heritage value.

One iconic pipeline is the CY O’Connor pipeline, which

delivers water from Perth to the Goldfi elds. In 2003, the

100-year anniversary of this pipeline was celebrated through

the National Trust of Australia’s Golden Pipeline project. The

Water Corporation contributed $1.3 million to this project to

preserve the heritage aspects of the Goldfi elds Water Supply

Scheme that delivers water from Mundaring to Kalgoorlie, a

part of the IWSS water grid.

It will ensure the outstanding engineering feat designed and

overseen by CY O’Connor is preserved for the community of

Western Australia.

30

Some other heritage-listed sites that the Water Corporation

own in the study area include:

• Mundaring Weir (National Trust) which is part of the

Perth to Kalgoorlie pipeline;

• the sewer ventilation stack in Highgate Perth. It is

the only existing sewer ventilation stack of its design

in the State. It opened in 1941 to ventilate Perth’s newly

introduced reticulated sewerage system; and

• the Canning Contour Channel on Brookton Highway

in Roleystone. This channel was used to transport

drinking water from Canning Dam to Gosnells between

1940 and 1975 and is the only one of its kind in Western

Australia.

Natural assets also have been shared by generations of

Western Australians. Waterways, wetlands, rivers, the ocean

and natural bushland all contribute to our outdoor lifestyle.

The Swan River, our metropolitan beaches and family

picnics at dam sites are enjoyed by the community for their

recreational and spiritual values. Water planning preserves

these natural heritage assets for the enjoyment of current

and future generations.

CATCHMENT PROTECTION AND DRINKING WATER QUALITY

Managing public drinking water catchments is essential to

public health and safety.

The Water Corporation is an advocate for source protection.

We support the catchment to tap multiple barrier,

risk-based framework outlined in the Australian Drinking

Water Guidelines.

The Department of Water, with the Water Corporation,

assesses and manages public drinking water source areas to

minimise potential risks from local activities and land uses.

Controlling land use in priority areas is critical to protect

water quality. The Department of Water has produced a note

entitled Land Use Compatibility in Public Drinking Water

Source Areas. This includes a table with a list of acceptable

land uses compatible with conditions or incompatible with

the three priority area classifi cations. These are:

• Priority 1 areas, which are managed to ensure that there

is no degradation of the drinking water source by

preventing the development of potentially harmful

activities in these areas;

• Priority 2 areas, which are managed to ensure that

there is no increased risk of water source contamination

or pollution; and

• Priority 3 areas, which manage the risk of pollution to

the water source from catchment activities.

OPTIONS FOR OUR WATER FUTURE 31

ABORIGINAL HERITAGE SITES AND NATIVE TITLE CLAIM AREAS IN THE PERTH - MANDURAH REGION

32

COMMITMENT TO DRINKING WATER QUALITY MANAGEMENT

SYSTEM ANALYSIS AND MANAGEMENT

SUPPORTING REQUIREMENTS

Assesment of the drinkingwater supply system

Preventive measures fordrinking water quality management

Operational proceduresand process control

Verification of drinking water quality

Management of incidentsand emergencies

Employee awarenessand training

Community involvementand awareness

Research and development

Documentation and reporting

REVIEW

Evaluationand audit

Review and continualimprovement

The Department of Water has completed over 70 Drinking

Water Source Protection Plans and is well progressed towards

completing plans for all 139 drinking water source areas.

The Water Corporation has prepared catchment

management strategies for metropolitan catchments which

address land use, water quality, vegetation, land forms and

hydrology and include implementation strategies. There

is also a Source Water Protection Strategy for the Perth

Seawater Desalination Plant.

As part of our commitment to the Australian Drinking Water

Guidelines we are also developing Water Safety Plans for

245 localities in Western Australia. These plans promote

near continuous monitoring at each key point in the supply

chain, from the source through to treatment, disinfection

and distribution to customers.

OPTIONS FOR OUR WATER FUTURE 33

PUBLIC DRINKING WATER SOURCE PROTECTION AREAS IN THE PERTH - MANDURAH REGION

34

HISTORICAL AND NATURAL HERITAGE SITES IN THE PERTH - MANDURAH REGION

CONNECT

The metropolitan and surrounding areas have an extensive

network of pipes and other infrastructure that allows us to

connect communities to water sources and deliver safe and

reliable water, wastewater and drainage services.

The IWSS water grid connects communities from the north

of Perth, east to the hills, through the city, to Mandurah and

at times, to other water supply systems for the South West

and Great Southern regions.

We connected the Goldfi elds to support the gold rush over

100 years ago. Since then, the water grid has connected

numerous small towns and farms along the way. Today over

75% of Western Australians are connected to our water grid.

Population growth, together with climate change means

that we must be more creative about how we deliver

services to meet our customer’s needs. This includes moving

water and wastewater around the system in the most

effi cient way, at levels of treatment that protect public

health and the environment.

This section provides information about how our water,

wastewater and drainage systems operate and how we

can optimise their use. Importantly, water service delivery

is linked to the land planning process and opportunities to

better integrate these activities are also explored.

WATER SERVICES

The IWSS water grid supplies water to customers. There are

four main components that are common to all water supply

schemes.

Water sources

Water sources collect or abstract water. We have four types

of sources:

• surface water sources – dams to collect and store

streamfl ows;

• groundwater sources – bores or wells that abstract

groundwater;

• seawater – from the ocean; and

• other sources such as drainage water, stormwater and

treated wastewater.

Traditionally, surface water and groundwater schemes were

the only sources used to supply Perth. Due to the impacts of

climate change other types of water sources have now been

added to the scheme. In 2004 the Kwinana Water Recycling

Plant was built to supply treated wastewater to industry in

Kwinana and in 2006, the fi rst seawater desalination plant

was built to supply Perth.

A feature of the IWSS water grid is the very large number of

sources supplying water to the scheme. All sources connect

into the water grid and combine to supply water to Perth

and surrounding areas.

The groundwater schemes are mainly located in the

Northern suburbs, while the surface water sources are

located in the Southern areas, in the hills. The water grid has

been developed so that the Northern groundwater schemes

can supply local areas and water can be transferred to

Southern suburbs.

Similarly, dam water supplies local areas and can be

transferred to Northern suburbs. The Perth Desalination

Plant supplies water to local areas and this water can be

banked - transferred into the dams for later use.

During periods of low storage in dams, groundwater sources

and the desalination plant supply the bulk of the Perth demand.

Water treatment

Source water is treated to meet the required standards of its

end use (for example, drinking water). The level of treatment

is dependent upon the quality of the source water and the

requirements of the end use.

Most of our dams have excellent water quality and only

minimal treatment is required, where chlorine and fl uoride

are added.

The majority of groundwater sources require more

treatment. Deep groundwater tends not to require treatment

but is generally blended with other treated water due to its

high temperature.

Water sources

Water treatment

Water transfer

Water distributionto customers

WATER SUPPLY SCHEME

36

OPTIONS FOR OUR WATER FUTURE 37

FUTURE WATER SOURCE OPTIONS

The Perth Seawater Desalination Plant is a complex

treatment plant involving various fi ltration processes

including reverse osmosis treatment. The same process is

proposed for the Southern Seawater Desalination Plant.

The Kwinana Water Recycling Plant includes various fi ltration

processes and reverse osmosis treatment.

Higher levels of treatment are generally more costly and

consume higher amounts of energy.

Water transfer

There is a very large network of water infrastructure that

delivers drinking water from sources and treatment plants to

the customers’ door. The network consists of pipes, pump

stations, valves, storage tanks and reservoirs designed to

deliver the required level of service.

Water is transferred from water sources and water

treatment plants to storage reservoirs and tanks located near

customers. Often the sources are located far away from the

demand areas, so transfer systems can be large. Water is

usually transferred through large pipelines or trunk mains, by

pumping or gravity systems.

Treated water is transferred from the various groundwater

treatment plants and dams to service reservoirs and tanks

in large trunk mains. Examples of these trunk mains are the

Stirling, South Dandalup, Serpentine and Canning trunk

mains, which transfer water from these Southern most

sources to Perth.

The service reservoirs and tanks are located in strategic

locations around Perth on hills to allow gravity to supply

water to customers. Examples of these are the Yokine,

Tamworth and Wanneroo reservoirs and the Bold Park and

Yokine high-level tanks.

In some of the Southern suburbs, distribution mains are

directly connected to trunk (major) mains without using a

reservoir or tank. Pressure reducing valves are used to reduce

high pressure in the trunk mains.

The long-term aim is to have all customers served directly

off reservoirs and tanks, as this improves the level of service.

This supply philosophy has been adopted in the future

planning for the IWSS water grid.

Water distribution to customers

After water transfer, water is delivered through smaller

reticulation mains directly to customers.

WASTEWATER SERVICES

The Water Corporation manages about 90% of Perth and

Mandurah’s wastewater through thirteen wastewater systems.

Beenyup, Subiaco and Woodman Point are large wastewater

systems that collectively serve more than 1.3 million people

in the metropolitan area. Medium sized systems in Point

Peron, Kwinana and Gordon Road (Mandurah) service over

100,000 people.

Small wastewater systems in Halls Head (Mandurah),

Caddadup (Mandurah) and Pinjarra serve around 15,000

people while four very small plants at Two Rocks, Yanchep,

Bullsbrook and Mundaring serve less than 5,000 people.

Wastewater collectionand transfer

Wastewatertreatment

Wastewater disposaland recycling

WASTEWATER SERVICES

38

WASTEWATER FLOWS DIRECTED TO WATER CORPORATION TREATMENT PLANTS OR INDIVIDUALLY MANAGED

Subiaco - 17% Gordon Rd - 2%

Kwinana - 1%

Pt. Peron - 4%

WoodmanPoint - 33%

Beenyup - 32%

Very Small - 0%

Small - 1% Individual - 10%

OPTIONS FOR OUR WATER FUTURE 39

AREAS SERVICED BY PERTH - MANDURAH WASTEWATER TREATMENT PLANTS

Any remaining wastewater that is not collected by the Water

Corporation is individually managed on site by homes and

industry through septic tank and leach drain systems.

Wastewater collection and transfer

Collection and transfer systems collect wastewater from

premises by pipes and transfer it to pump stations and

treatment plants. The quality of the wastewater collected

is closely monitored to exclude or minimise chemicals and

pollutants entering the wastewater system.

In Perth, most sewers use gravity to move wastewater

around, making them very energy effi cient. There are also

numerous pumping systems where gravity sewers are not

possible. There are some vacuum sewers in the canal areas

near Mandurah. Far away from wastewater treatment

plants, the pipes are small, as they tend to deal with smaller

volumes. As the volume of wastewater increases closer to

the treatment plant, pipe sizes increase.

In the transfer system, pipes and pump stations that are

prone to odour generation are sealed. In a few cases, vents

and odour scrubbers are used to treat and reduce the odours.

Wastewater can overfl ow prior to treatment if sewer mains

are blocked or broken (generally due to tree roots) or pump

stations fail (generally due to power failures or bursting

pressure mains). To minimise the risk of this occurring, the

Water Corporation ensures its assets are well maintained.

In addition, extra measures are in place to minimise the

consequence of failure, such as the use of remote monitoring,

emergency storage, standby power generation, standby

pumps and duplicate pressure mains at certain pump stations.

Wastewater treatment

Wastewater is 99.97% water and some dissolved and

suspended matter such as solids, oil and greases, detergents,

nutrients, heavy metals and bacteria, which need to be

removed before discharge to the environment or recycling

for other uses.

Wastewater treatment plants treat wastewater to a quality

suitable for recycling or discharge.

Primary treatment settles out or clarifi es about 50% to

60% of the suspended matter in wastewater. The treated

wastewater is suitable for discharge through a long ocean

outfall. This is used at the Point Peron wastewater treatment

plant and is the practice in the large Sydney treatment plants.

Secondary treatment is typically a biological treatment

process that is designed to remove suspended solids

and 85% of the organic matter. The most commonly

used secondary treatment processes are activated-sludge

processes and lagoons. Additional sand fi ltration and

disinfection may also be used.

Tertiary (or advanced treatment) is principally designed to

remove nutrients, such as phosphorus and/or nitrogen. Most

suspended solids are also removed.

Tertiary treatment may additionally target other

contaminants of concern, such as toxins and salt. Typical

tertiary treatment processes include biological nutrient

removal, enhanced pond treatment systems, reverse osmosis

and advanced fi ltration systems.

Most of Perth’s treatment plants are tertiary plants, which

treat water to a high standard and are designed to reduce

nitrogen to less than 15 milligrams per litre. Where recycling

for irrigation occurs there is also sand fi ltration and

disinfection. For industrial recycling in the Kwinana Industrial

Area, micro fi ltration and reverse osmosis are used.

Some Perth wastewater treatment plants have been covered to

reduce odours to the atmosphere. The Water Corporation has

spent over $60 million over the past 10 years on this program.

In addition, there are buffer areas around each treatment plant

to reduce the exposure of homes and businesses to odour.

Wastewater disposal and recycling

Treated wastewater is recycled or discharged to waterways

or land.

In the greater metropolitan area, 81% of all treated

wastewater is safely discharged to the ocean and about

5% recycled. 4% recharges groundwater aquifers and the

balance (not managed by the Water Corporation) is disposed

through septic tank systems.

Most treated wastewater from major plants is discharged

to the ocean from outlets at Ocean Reef, Swanbourne and

Cape Peron.

Ocean discharge is most commonly used around the world

to discharge treated wastewater from larger coastal cities.

The wastewater is treated to a standard to protect ocean

water quality. It can be an environmentally acceptable and

economical method, available all year round.

Of the major Australian cities only Sydney has longer outlets,

but they discharge primary treated wastewater. Adelaide

has tertiary treatment but only short outlets, while Brisbane

discharges tertiary treated wastewater to the river, and

Melbourne has shoreline discharges of secondary treated

wastewater.

40

OPTIONS FOR OUR WATER FUTURE

PERCENTAGE OF TREATED WASTEWATER DISCHARGED TO THE ENVIRONMENT OR RECYCLED

Ocean - 81%

Groundwater - 4%

Rivers/Streams - 0.01% GroundwaterSeptic Tanks - 10%

Recycled - 5%

Perth compares very favourably with its major wastewater

treatment plants discharging highly treated (tertiary) wastewater

through long (greater than 1 kilometre) ocean outlets.

The Kwinana, Gordon Road, Halls Head, Caddadup, Two

Rocks and Yanchep wastewater treatment plants recharge

groundwater with treated wastewater. In Mundaring, the

wastewater is discharged to a stream in winter and used to

irrigate public open space in summer.

In the Perth - Mandurah area, recycled water from our

wastewater treatment plants is used:

• for processes within the wastewater treatment plant;

• to provide water for industry at Kwinana and Pinjarra;

and

• for the irrigation of public open space.

A residual of the wastewater treatment process is biosolids

that are recycled (as a soil supplement for agricultural use) or

disposed to landfi ll.

Septic systems and infi ll sewerage

Some lots in the Perth - Mandurah area use septic tanks and

leach drains. Generally these are located in an arc around

the city from Scarborough to Melville. The majority of these

residential lots were developed in the post-second World

War era on large blocks with sandy soils. There were also

signifi cant unsewered areas in localities containing more clay

soils including Midland and Kelmscott.

In the mid 1960s, approximately half of Perth was connected

to the wastewater treatment system. The then Metropolitan

Water Board introduced the requirement for land

developers to connect to reticulated sewerage. In 1981, the

Government Sewerage Policy was introduced.

The policy was introduced as a result of:

• the large number of septic tank and leach drain systems

in the Gwelup Groundwater Public Drinking Water

Supply Area, which had the potential to contaminate

drinking water supplies;

• failing septic systems in clay soils near the river;

• the contribution of nutrients to the Swan River, lakes and

wetlands from all septic systems; and

• the constraint that septic tank systems placed on higher

density development, contributing to Perth’s urban sprawl.

The State Government introduced an $800 million Infi ll

Sewerage Program in 1994. This program is nearing

completion, with about 90% of all Perth properties connected

to the Water Corporation wastewater treatment system.

The Water Corporation is proposing to spend over

$110 million on Infi ll Sewerage over the next 10 years.

Approximately $65 million will be spent in Perth and $45

million in Mandurah.

DRAINAGE SERVICES

A drainage system is a network of drains and associated

infrastructure that manages the collection and transportation

of surplus water, such as stormwater. By managing fl ooding

to minimise property impacts, it allows for the highest and

best use of land, having due regard for the need to protect

the natural environment.

Perth is criss-crossed by a drainage network consisting

of main drains (owned and managed by the Water

Corporation) and local drains (owned and managed by Local

Government). These collect water from drainage catchments

and move it away from areas susceptible to fl ooding to

drainage sumps (pits) where it recharges groundwater, lakes,

wetlands and the ocean.

Local Government manages about 80% of all drainage in

Perth. The Water Corporation manages the balance and

there are over 325,000 homes and business connected to

our drainage network.

41

The Department of Water is responsible for drainage

planning with the preparation of Drainage and Water

Management Plans. These plans identify drainage

infrastructure and associated land requirements, while

managing the environmental values of the catchment. They

ensure all land development includes provision for drainage

systems to protect against the risk of fl ooding for both

minor and major storm events.

The Department of Water is fi nalising a study into the

availability of stormwater from the drainage network in Perth.

Stormwater is increasingly being managed on site to

recharge groundwater that can benefi t the natural

environment and may be accessed through sustainable use

of groundwater systems.

Drainage collection

Stormwater is typically collected from:

• natural catchments;

• roof and site runoff from buildings; and

• streets and other fl at surfaces such as car parks.

Stormwater is directed into drains, which can be in the form

of pipes, open channels, streams and creeks. Drainage water

fl ows into compensating or detention basins, where it soaks

into the ground. This recharges groundwater in local areas. Due

to the fact that Perth has sandy soils, opportunities to recharge

groundwater are maximised through our drainage systems.

Drainage transfer

Drainage water that is not recharged to the ground is

transported from collection areas and retention basins

through main drains. These drains may be in the form of

large pipes or open channels. They are usually large in size

and cut across multiple Local Government areas.

The Water Corporation constructs and maintains these

conveyance systems to meet the level of service as

specifi ed in the Water Corporation’s Operating Licence and

Customer Charter. In summary, we provide urban drainage

infrastructure to protect against fl ooding for the peak fl ows

of stormwater runoff in:

• urban residential areas for a one in fi ve year peak

rainfall event; and

• commercial or industrial areas for a one in 10 year

peak rainfall event.

The Water Corporation is also responsible for rural drains in

the outer - metropolitan area.

Local Government has a requirement to provide fl ood paths

through the catchment to manage major storm events.

Drainage treatment

The Stormwater Management Manual prepared by the

Department of Water identifi es a number of different treatment

methods to improve water quality through the drainage

system. These treatments can be located within both Local

Government and Water Corporation drains. Non-structural

approaches such as managing fertiliser use are also promoted.

The Department of Water and CSIRO are jointly developing

a research program to better understand the most cost

effective methods of improving water quality. The Water

Corporation is contributing to this research.

In Perth, drainage water is most often discharged to the

ground through detention basins. Only excess drainage

water is discharged to watercourses or to the ocean.

Due to the effi ciency of soak wells and the drainage

system as a whole, 90% of the estimated 480 gigalitres of

average annual rainfall in Perth is productively recharged to

groundwater systems and supports associated ecosystems.

The remaining 10% fi nds its way out to rivers and the ocean.

Drainagecollection

Drainagetransfer

Drainage dischargeand recycling

DRAINAGE SERVICES

Drainagetreatment

42

OPTIONS FOR OUR WATER FUTURE 43

DRAINAGE CATCHMENTS IN THE PERTH - MANDURAH REGION

Options to connect to the drainage system

Increasingly, drainage water is being retained within

developments under the principles of water sensitive urban

design as part of the local water balance. The Department

of Water is responsible for arterial drainage planning in

Western Australia and the preparation of Drainage and

Water Management Plans (DWMP).

The State Water Plan 2007 identifi ed a number of districts

that require a DWMP to be prepared as a consequence of

land development.

DRAINAGE WATER MANAGEMENT PLANS

Drainage Water

Management Plan

Location Drainage responsibility

Southern River Forrestdale, Wungong Local government drains discharge

into the Forrestdale main drain

Byford Byford Local government drains discharge

into the Oaklands rural drain

downstream of the development area

Jandakot Mandogalup - Bertram (includes Wellard) Upper

Peel MD catchment

Local government drains discharge

into the Peel main drain.

Interim Murray Ravenswood, Pinjarra, Yunderup, North Dandalup,

Nambeelup, Lower Serpentine

Primarily local government drains,

with two rural drains in the southern

catchment

District Murray Ravenswood, Pinjarra West, Pinjarra Central,

Pinjarra North, North Dandalup, Dandalup Upper

Nambeelup, Nambeelup, Lower Serpentine

Caversham - West Swan Caversham - West Swan, Viveash Local government drains

Mundijong - Whitby Mundijong - Whitby Local government drains discharge

into the rural drainage scheme

downstream of the development area

Baldivis - Karnup Baldivis - Karnup Primarily Local government drains

with a portion of the catchment

discharging into the Peel main drain

Keralup/North Mandurah North Mandurah, Lakelands, Stakehill, Keralup Local government drains discharge

into the Dirk Brook rural drain.

Jarrahdale Serpentine, Jarrahdale, Stoneville Local government drains

East Wanneroo East Wanneroo, Carramar, Banksia Grove, Madeley Local government drains

Alkimos Alkimos Local government drains

44

OPTIONS FOR OUR WATER FUTURE

CONNECTING WATER FOREVER WITH LAND PLANNING

Current and future developments are supported by the

provision of secure, safe, sustainable water, wastewater

and drainage services. The continued integration of land

and water planning is essential to ensure that future

development can be achieved sustainably.

The Water Corporation supports land and water planning to

meet the needs of our cities, towns and communities, now

and in the future.

In Western Australia, the Western Australian Planning

Commission is responsible for planning land development.

Final approval for land development involves both the Western

Australian Planning Commission and Local Government.

The Department for Planning and Infrastructure administers

policies on behalf of the Planning Commission and ensures

that Local Government approvals are consistent with

statutory (legally binding) and non-statutory (strategic) plans

and policy. The Department is also responsible for optimising

investment in infrastructure (such as roads, power, water,

wastewater and ports) in Western Australia to facilitate the

development and expansion of the State.

The Water Corporation supports the need for improvements

in water use effi ciency in urban areas. The greatest leverage

for sustainable water outcomes occurs at the strategic land

planning stage.

This is particularly the case when decisions are made around

water sources for drinking and other use and the need for

appropriate drainage and wastewater services. Sound land

planning should support the preservation of key natural

assets (such as rivers, waterways, wetlands, groundwater

resources) and water infrastructure (such as treatment plants

and pump stations).

Input into land planning process

The Department of Water has a key role to play to integrate

water resource management with land planning. The Water

Corporation supports these activities as a planning agency

through:

• input into strategic planning exercises such as Network City;

• input into statutory planning policy such as Western

Australian Planning Commission policies 2.7 (source

protection) and 2.9 (water resources); and

• input into metropolitan and regional planning schemes.

A water balance should be completed at regional scales to

identify current and potential water resources and expected

demand. The Water Corporation supports this work by advising

on the form and scale of water infrastructure and programs,

through planning informed by community engagement.

In this way, the optimum balance of new sources, water use

effi ciency initiatives, water quality strategies, drainage and

water sensitive urban design can be integrated with land use

requirements for developments.

This type of planning is new in Western Australia. Water

Forever will identify further priorities in this area.

Development of essential water infrastructure

Land development cannot progress without access to water

and wastewater services. The Water Corporation is a partner

in the land planning process.

The Water Corporation relies on timely and robust

metropolitan, regional and town planning to identify future

needs for water and wastewater services and sites to

develop these services. In addition, roads and power must be

in place well in advance to allow adequate time for planning,

design, project delivery and commissioning of infrastructure

to meet the needs of a growing Western Australia.

Delays in land planning, drainage planning, securing sites

for infrastructure, provision of access roads and suitable

and adequate power supplies have an adverse impact on

water service delivery. If the timing of the need for the

water service doesn’t change, this means that the time for

community engagement, project delivery and us to conduct

detailed planning is compromised.

In some instances, this has been the experience of the Water

Corporation. Specifi c challenges to be addressed include:

• inconsistencies and long lead times to align metropolitan

and regional planning scheme amendments with local

town planning schemes;

• roads and power supplies are not always in place

in a timely manner to support essential water services

infrastructure; and

• the process to obtain sites and reservations for

infrastructure corridors for water infrastructure can be

uncertain and prolonged.

45

The draft Water Forever plan will identify key sites required

in the study area to secure essential water infrastructure. At

this time, sites are expected to be required for new:

• desalination plants;

• large water reservoirs;

• wastewater treatment plants;

• water treatment plants; and

• recycling facilities.

As a general rule, the Water Corporation seeks to purchase

land for these works to ensure compatible land use

approvals. In particular, the land planning process at all levels

needs to support adequate buffers for infrastructure.

The Water Corporation relies on land planning to secure

easements to allow for infrastructure corridors to connect

new infrastructure to customers. The land planning process

is also relied on to ensure adequate source protection for

surface and groundwater sources. Source protection is vital

for public health and helps supports ecosystem health.

Protection of water infrastructure

There is over $13 billion of investment in water, wastewater

and drainage infrastructure in the area covered by this study.

Water assets have very long lives, often 100 to 200 years.

Once a dam, desalination plant or wastewater treatment

plant has been built, there is an expectation that it will be

maintained and renewed to support water services for future

generations. This supports service delivery, makes economic

sense and provides certainty for adjacent land holders and

the community.

However, land planning decisions do not always adequately

support our investment in water infrastructure. This can happen

through the rezoning of land or through the loss of buffer areas

surrounding key infrastructure, due to urban encroachment.

This risk is particularly high for wastewater treatment plants.

Without these plants, new land cannot be developed and we

cannot recycle water to industry, for parks and other uses.

The draft Water Forever plan will identify strategies and

actions to support better protection of key water assets.

Lot servicing

The Water Corporation supplies water services to over

98% of the State’s population. In the study area, Western

Australia’s land planning policies generally require access to

reticulated scheme water and wastewater supplies before

urban development approvals can be granted.

Landowners may supplement these scheme services with

garden bores, rainwater tanks or greywater systems, subject

to approval from the Department of Health and the relevant

Local Government authority.

The Water Corporation is a referral agency for subdivision

approvals and a clearing authority for water, wastewater,

drainage and land use conditions.

The Water Corporation has a responsibility to connect new

lots to water and wastewater services under our Operating

Licence issued by the Economic Regulation Authority. Under

our Customer Charter issued as part of this licence, we

commit to installing or activating a water service within a

fi xed period of time, once the conditions of connection have

been satisfi ed.

The Water Corporation works closely with the development

industry to ensure that we facilitate land development and

servicing.

46

CREATE

Living in or near a city that is growing at the rate that Perth

is growing provides opportunities for us to create new water

and wastewater services to meet our needs.

This section examines water and wastewater options for the

future.

Meeting growing demand for water services

The IWSS water grid supplies water to meet consumer

demand. As water demand grows, so must our water source

capacity to meet that demand.

The amount that the IWSS water grid can supply varies

every year. Water available from dams is directly impacted by

rainfall. The amount of water available from groundwater

can also vary somewhat from year to year, although most

groundwater reserves are large and can withstand some

fl uctuation in annual rainfall.

Due to signifi cant investment over the past fi ve years in

recycling and desalination, the IWSS water grid is becoming less

dependent on rainfall and more resilient in periods of drought.

Based on the population projections from the Western

Australian Planning Commission, we have estimated that

there will be total demand for water from the IWSS water

grid of 320 gigalitres by 2020. Based on CSIRO rainfall

projections, we estimate that there will be a small gap

between demand and system yield of 5 gigalitres at that time.

New water solutions will be required prior to 2020 to meet

this demand and increasing future demand for water, as the

population grows. That may include signifi cant investment in a

single source, or a range of smaller sources and water effi ciency.

The gap between supply and demand will continue to

grow due to increasing demand and expected reductions

in rainfall. By 2060, there is a possible gap of 255 gigalitres

between water available in the system and demand, without

further investment.

Planning ahead now helps us to make wise choices and

keep options open for the future.

Summary of demand and supply water options

Information sheets have been developed on the many

options for our water future by 2020, 2030 and 2060. These

include options for customers connected to the IWSS water

grid to recycle or use less scheme water. These information

sheets can be downloaded from

www.watercorporation.com.au/waterforever.

SUPPLY DEMAND GAP, WITHOUT FURTHER INVESTMENT, BY 2020, 2030 AND 2060

Year Estimated

water

demand

Possible

system yield

Supply -

demand gap

Gigalitres a year

2020 320 315 5

2030 360 285 75

2060 470 215 255

The table over the page provides an overview of water use

effi ciency and source options that could be developed. Due

to signifi cant climate uncertainty in latter years, we have not

included estimates for climate dependent sources in 2060.

These options may still have a role in our water future, but

greater certainty is required to estimate the amount they

may contribute to IWSS supply security.

Cloud seeding, groundwater from South West Yarragadee and

moving water from the Kimberley are not being considered

by the Water Corporation for water supply to the IWSS water

grid and are not included in the table over the page.

Uncertainties in future source yields and costings

Each prospective water source and initiative is evaluated for

their yield (amount available for use in the IWSS water grid),

rainfall dependency, energy use and cost per kilolitre.

Most of the work to estimate the yield of each source option

was undertaken based on the standard climate period used

by the Department of Water to forecast available water

resources in relatively wet years from 1975 – 2002.

As noted, too much uncertainty exists with rainfall

projections to estimate yields from climate dependent

sources by 2060. Rapid changes in rainfall have already

occurred and we require more information to accurately

forecast the impact of future rainfall on climate dependent

water sources. Monitoring actual rainfalls and continuing to

invest in knowledge of our climate will progressively provide

more information to assist planning.

Estimates have been included for rainfall independent

sources such as water use effi ciency initiatives, water

recycling and seawater desalination.

48

OPTIONS FOR OUR WATER FUTURE 49

WATER SOURCE AND EFFICIENCY OPTIONS TO MEET WATER DEMAND TO 2060

IWSS water supply and effi ciency options (gigalitres a year) 2020 2030 2060

Water use effi ciency Water use effi ciency initiatives 4 12 40

Individual alternative water

supplies

Rainwater tanks 5 10 Not known

Garden bores 8 15 Not known

Greywater systems 3 6 15

Community alternative

water supplies

Community bore systems 6 10 Not known

Sewer mining systems 5 10 20

Community 3rd pipe system 5 10 20

Water recycling Groundwater replenishment 25 50 100

Industrial uses 5 30 50

Desalination Southern Seawater

Desalination Plant (Phase 2)

50 50 50

Other sites 100 200

Esperance pipeline 15 20 20

Surface water sources Water trading 7 7 Not known

Brunswick dam 30 Not known

Wellington system:

• Collie basin 10 10 Not known

• Wellington dam 14 Not known

• Water trading 16 Not known

Groundwater sources North West Coastal 10 20 Not known

Jandakot expansion 3 3 Not known

Gingin - Jurien 10 20 Not known

Karnup - Dandalup 5 10 Not known

Other options Catchment management 5 25 Not known

Total of Climate Independent sources and initiatives 112 288 515

Total of Climate Dependent sources 69 190 Not known

Key: Climate independent Climate dependent

50

It is important to note that groundwater source costs are for

local use. They do not include connection to the IWSS water

grid or additional storage costs, which can be signifi cant.

The location of a water source, the demand centre it will

supply and the need for additional storage all need to be

considered to fully cost a source option.

WATER USE EFFICIENCY INITIATIVES

Current water use effi ciency initiatives are expected to

reduce demand to 145 kilolitres per person (for residential

and commercial use) per year by 2012.

Further water use effi ciency initiatives could provide further

savings, and partially reduce the need for new sources.

1. Water effi ciency programs (40% future savings)

More savings could be achieved by more investment in

Waterwise Programs and changes to building codes.

2. Increased density living (30% future savings)

The future trend in the metropolitan area is for increasing

numbers of multi-residential dwellings. Currently the ratio

of single residential to multi-residential dwellings is 71% to

29%. It is estimated that this ratio will be in the order of

55% to 45% by 2060. The move to smaller dwellings with

smaller gardens will reduce water consumption.

3. Technological advancements (20% future savings)

More water effi cient appliances and irrigation systems,

supported by the Water Effi ciency Labelling Scheme, Smart

Watermark, rebate and retro-fi t schemes could save more

water in businesses and homes.

4. Behavioural change (10% future savings)

Greater environmental awareness promoted by advertising

and behavioural change programs including comparative

billing and social marketing could alter people’s water usage

habits and save more water.

These programs could achieve savings over a range,

dependent on the degree to which customers are

encouraged to adopt more water effi cient habits or

regulation is used to mandate change.

ALTERNATIVE WATER SUPPLIES

Traditionally, we have used drinking water supplies for

almost all household and business water uses. We are now

beginning to integrate alternative water supplies for non-

drinking water needs. These include toilet fl ushing, garden

watering and water used in the laundry.

In general, these alternative water supplies can provide

individual households and businesses with small reductions

in scheme water usage. The impact that they may have in

helping us to meet our water future will be the product of

the saving of each source at a business or household level

and the degree of penetration across the metropolitan area,

in both new and existing buildings.

On average, rainwater tanks are estimated to save up to 50

kilolitres a year when plumbed for indoor use. Garden bores

may be plumbed for internal use as part of a community

bore scheme. In this instance, they may save 71 kilolitres

water from the IWSS water grid in one year.

Greywater systems are used to water gardens. On average,

they can supply about 60 kilolitres of water a year for this use.

For health purposes, all alternative water sources for in home

use require a back up water supply. In almost all instances in

the metropolitan area, this is the IWSS water grid.

The State Government is supporting the use of alternative

water supplies through the introduction of a program of

changes to the Building Code known as Five Star Plus. In the

second stage of this program, proposed for introduction in

2008, new residential and commercial buildings will require

plumbing to be installed to allow for ease of connection to

an alternative water supply for non-drinking water uses like

toilet fl ushing.

Demand programs Cost Savings by 2060

(gigalitres a year)

Rainfall dependence Energy usage

Residential < $1.50 a kilolitre 28 - 84 Low Low

Business < $1.50 a kilolitre 9 - 25 Low Low

Other < $1.50 a kilolitre 3 - 10 Low Low

POTENTIAL WATER EFFICIENCY SAVINGS

OPTIONS FOR OUR WATER FUTURE

Rainwater tanks

Rainwater tanks have supplied rural water needs in Western

Australia for many years. The Department of Health supports

the use of rainwater tanks in Perth for non-drinking water

uses. There is some increased risk of pollution by airborne

chemical and microbiological contamination when rainwater

tanks are used for drinking water purposes.

The amount of water collected by a rainwater tank varies

and major determinants include:

• size of roof area;

• indoor and outdoor use or outdoor use only;

• rainfall patterns;

• number of household occupants (and usage); and

• tank size.

Rainwater tanks rely on rainfall, and storage capacity is limited

in urban areas by the available space (generally two kilolitres

but could be as big as ten kilolitres). They are best used

frequently, as this increases the number of times they can be

refi lled (such as connecting for toilet and clothes washing use).

Perth gets 70% of its rainfall in four months during winter

and spring. This means that the tanks may only be fi lled

once or twice if they are only used for outdoor water use in

a long, dry summer.

Most local councils require that a building application be

approved before a rainwater tank can be installed. The State

Government provides a Waterwise Rebate of up to $600 for

tanks greater than 2 kilolitres that are plumbed into the house.

Garden bores

Garden bores draw water from shallow groundwater,

generally to about 50 metres in depth, although some can

be as deep as 100 metres. This source of water is fed by

rainfall, which percolates into the ground across most of

the Swan Coastal Plain. Garden bores can provide a fi t for

purpose water source and can take pressure off scheme

drinking water supplies.

It is estimated that there are about 164,000 garden

bores in Western Australia, with about 90% in the Perth

metropolitan area. These bores supply over 20% of all

household water.

51

POTENTIAL ALTERNATIVE WATER SOURCES

Source option Cost Supply by 2030 Supply by 2060 Rainfall

dependence

Energy usage

Rainwater tanks $2 - $3 a

kilolitre

10 gigalitres Not known High Low

Garden bores Less than $1 a

kilolitre

15 gigalitres Not known Medium Low

Greywater systems $4.50 a kilolitre 6 gigalitres 15 gigalitres Low Low

Community bore systems $1 a kilolitre for

untreated, and

$4 a kilolitre for

treated water

10 gigalitres Not known Medium Low

Sewer mining systems $4 - $8 a

kilolitre

10 gigalitres 20 gigalitres Low Medium

Community third pipe

systems

$4 - $6 a

kilolitre

10 gigalitres 20 gigalitres Low Medium

Some areas in Perth are unsuitable for a garden bore. These

areas are generally:

• close to wetlands;

• near the foothills and places with clay or alluvial soils;

• within about 200 metres of the Swan River estuary or

the ocean, including the Cottesloe Peninsula where salt

water can be drawn into the bore;

• near industrial and waste disposal sites where

groundwater may be contaminated; and

• in locations prone to acid sulphate soils.

Since February 2003 the State Government has supported

the installation of garden bores through a Waterwise rebate

to people in areas where bores are suitable according to the

Perth Groundwater Atlas. Over 21,000 rebates have been

granted since the program began (about 5,000 a year).

Garden bores depend on rainfall to recharge groundwater.

As rainfall in the South West of Western Australia has fallen

over the past 30 years, we need to use this resource wisely.

The Department of Water is currently updating the Perth

Groundwater Atlas. Rebates for garden bores will no longer

be available for areas deemed unsuitable for additional bores.

In October 2007, the State Government implemented

permanent Water Effi ciency Measures (WEMs) that impact

the use of garden bores. In the Perth region, garden bores

are now subject to a three-day a week sprinkler roster

system. This is adequate to maintain a garden without

wasting water and avoids the risks of overuse.

The potential for additional garden bores is generally

decreasing due to a number of factors, including:

• introduction of the three day a week sprinkler rostering

system for bores;

• loss of rebate in some areas;

• smaller lot sizes making them less economical; and

• waterwise gardens requiring less water to maintain.

It is estimated that between 2,000 to 3,000 new garden

bores will be added each year over the next 10 years.

Greywater

Greywater is wastewater that comes from the bath, spa,

shower, bathroom washbasins, clothes washing machine,

laundry trough, dishwasher and kitchen sink. Greywater

from the kitchen sink is generally not recycled due to the

contaminants it contains.

In 2007, the average household produced about 90 kilolitres

of recyclable greywater from the bathroom and laundry.

Reusing greywater may involve bucketing or installing a

greywater diversion system, which diverts greywater to a

subsurface irrigation system, after fi ltration. Greywater recycling

involves installing a system that treats greywater to a quality for

other uses such as toilet fl ushing or sprinkler irrigation.

Both treatment systems need to be approved by the

Department of Health. They have published a Code of

Practice on the reuse and recycling of greywater, which

includes details on how to safely bucket greywater and how

to go about safely installing and maintaining an approved

greywater system. They also publish a list of all greywater

systems approved for use in Western Australia.

Waterwise Rebates for greywater systems were introduced

in February 2003 as part of the Waterwise Rebate Program.

They currently attract a Government rebate of up to $500.

By January 2008 only 144 households had applied for a

rebate compared with over 21,000 rebates for garden bores

and over 13,000 for rainwater tanks.

Community bores

The Water Corporation has been working with developers,

Government departments and local councils to investigate

the use of community bores (jointly owned garden bores) for

outside watering and use in the home. These bores may help

to conserve water as they are monitored and can be linked

to weather stations to limit unnecessary watering.

Community bores generally rely on the superfi cial aquifer

and as such may be impacted by falling water levels in

times where there is low rainfall. They also require piping

to connect the bores to homes and buildings, and this

duplication can be expensive.

Sewer mining

Wastewater can be sourced directly from pipes in

the wastewater transfer system before it reaches the

wastewater treatment plant. This is known as sewer mining.

Appropriately treated, water from sewer mining can be used

in industrial applications and to irrigate public open space.

Sewer mining requires wastewater to be treated in a stand-

alone system. It is most economical where use is close to a

wastewater treatment main. Care needs to be taken that

enough wastewater remains in the main to enable the

wastewater system to work.

Historically, groundwater has provided a safer and more cost

effective alternative to sewer mining in the metropolitan area.

The use of sewer mining in the study area is expected to be

most feasible in areas where groundwater is not available.

52

OPTIONS FOR OUR WATER FUTURE

Third pipe wastewater recycling

Water can be sourced from greywater, treated wastewater or

drainage water for non-drinking uses in and around the home.

This is generally referred to as a ‘third pipe’ system as it requires

an additional pipeline to the house (separate from the existing

drinking water and wastewater pipes) to supply the water.

The water could be used for external uses such as garden

watering and car washing as well as some domestic internal

uses such as toilet fl ushing.

WATER RECYCLING

Water is considered recycled when wastewater or drainage

water (stormwater) is appropriately treated and supplied to

suitable end uses such as:

• industrial use;

• groundwater replenishment for drinking;

• watering of public open space such as parks and golf

courses; and

• agriculture.

In April 2007, the Premier announced that a State Water

Recycling Strategy would be developed to improve water

use effi ciency and water recycling in Western Australia. This

strategy supports the State Water Plan 2007 water policy

framework to ‘use and recycle water wisely’.

The Water Corporation participated in the development of

the strategy and is considering ways to use recycled water.

Some of these options can be used to meet projected

demand in water use.

There is signifi cant potential to recycle water for industrial

use. For example, the existing Kwinana Water Recycling

Plant was designed to accommodate a 60% increase

of current capacity to 10 gigalitres a year. The Water

Corporation has planning in place to develop this additional

source, subject to fi nalising funding arrangements.

There are also opportunities to provide recycled water to

other industrial locations. We support the provision of a third

pipe in new industrial areas to facilitate more water recycling.

The Water Corporation is undertaking a trial at the Beenyup

Wastewater Treatment Plant in Craigie to test the feasibility

of replenishing groundwater with highly treated wastewater.

Subject to the outcomes of the technical feasibility of the

trial and community acceptance, a 25 gigalitre a year source

could be developed by 2020 for public drinking water supply.

Other uses, such as recycled water for agriculture and public

open space, generally do not relieve demand from the IWSS

water grid, because we do not currently provide water for

these purposes. Recycled water however, may provide the

right alternative for these applications particularly where

groundwater is scarce.

DESALINATION

The Perth Seawater Desalination Plant has been operational

since October 2006, delivering 45 gigalitres a year of

safe, reliable drinking water to Perth. The plant’s energy

requirements are purchased from the Emu Downs Wind

Farm and there have been no adverse impacts on the water

quality of Cockburn Sound, strictly monitored as a condition

of environmental approval.

Work to design and obtain regulatory approvals for

the proposed Southern Seawater Desalination Plant at

Binningup, 150 kilometres South of Perth, is progressing.

The plant is designed to deliver a further 50 gigalitres of

water a year, about 16% of total supply, by 2011. This site

could be expanded in the future to accommodate another

50 gigalitres a year.

53

POTENTIAL RECYCLED WATER SOURCES

Source option Cost Supply by 2030 Supply by 2060 Rainfall

dependence

Energy usage

Groundwater

replenishment

$1.50 - $3 a

kilolitre

50 gigalitres 100 gigalitres Low Medium

Industrial recycling $1 - $2 a kilolitre 30 gigalitres 50 gigalitres Low Medium

The major advantage of seawater desalination is that it is

rainfall independent. The plants can deliver a continuous

stream of safe drinking water, which can be used straight

away or banked into dams for later use.

More plants could be constructed in other locations around

Perth to meet future water supply needs. The Water

Corporation is undertaking a detailed study to determine

future options for desalination plant sites.

Another major consideration is energy. A desalination plant

uses 6 to 10 times more energy to produce a kilolitre of

water than sourcing groundwater.

In 2005, United Utilities Australia proposed an alternative

drinking water source for the Goldfi elds and Agricultural

regions and the Perth metropolitan area. They proposed

that water be sourced from a seawater desalination plant at

Esperance and piped 385 kilometres to Kalgoorlie. The water

would mainly be used for mining operations in the area and

for domestic water supply in Kalgoorlie. It would also provide

a drinking water source for Esperance.

The seawater desalination pipeline would result in the

existing Goldfi elds and Agricultural water supply pipeline

to Kalgoorlie terminating at Southern Cross. The existing

scheme would remain predominantly as a scheme for

agricultural towns and farmlands.

The State Government reviewed the project and found that

at the time it was not the most economical option.

In general, desalination is a much more expensive source of

water than traditional surface and groundwater resources.

This is infl uenced by a number of factors including process

design, pumping distance, need for new storage, energy

costs, and construction. Final costs need to be informed by

specifi c site considerations.

Other social and environmental issues may need to

be considered for each plant, depending on the site

location. These are addressed in site selection and detailed

infrastructure planning with community engagement.

Consideration has also been given to desalinating saline

groundwater from country towns. Saline groundwater has

been identifi ed as a problem in 38 rural towns in Western

Australia, threatening roads, buildings and other infrastructure.

A proactive approach to address this issue has been a

collaborative effort between the Department of Agriculture

and Food, Local Governments, CSIRO and other agencies to

develop water management plans for some of these towns.

This work has identifi ed that the best option is to use this

surplus water, treated to an appropriate standard, to irrigate

parks and other non-drinking water uses. Using this water

as a substitute for drinking water supply proved to be too

costly in most instances. Where it does make sense it will be

explored as a scheme option for the local town, to minimise

pumping costs.

SURFACE WATER SOURCES

Most cities around the world source their drinking water

from rivers and dams.

Similarly, up until about 30 years ago, almost all scheme

water used by customers in Perth and the Goldfi elds and

Agricultural regions came from surface water resources in

the Darling Scarp. These dams provided a reliable source of

water as a result of comparatively wet years.

The last major storage dam built for Perth was the Harvey

Dam, located in the South West of the State, to further

augment the IWSS water grid during this period of reducing

water source yields.

POTENTIAL DESALINATED SEAWATER SOURCES

Source option Cost Supply by 2030 Supply by 2060 Rainfall

dependence

Energy usage

Seawater Desalination $2 - $3 a

kilolitre

150 gigalitres 250 gigalitres Low High

United Utilities - Esperance

to Kalgoorlie supply

$2 - $3 a

kilolitre

20 gigalitres 20 gigalitres Low High

54

OPTIONS FOR OUR WATER FUTURE

Dams interrupt natural river systems and impact downstream

fl ows and ecosystems. The Water Corporation manages

surface water catchments to protect drinking water quality

and minimise adverse environmental impacts, together with

the Department of Water and Department for Environment

and Conservation.

There are a number of surface water options that have

been considered to meet Perth’s future water demand. They

are entirely dependent on rainfall. This creates signifi cant

uncertainty for these resources in the future; particularly

those located in the Southern half of the State where rainfall

is projected to decline.

Water trading - Harvey

Water trading is about buying a water entitlement from a

licensed user. This limits additional impacts on the water

resource and can provide a revenue source for the seller. Due

to the high cost of securing public water supply, this can also

be a cost effective option for water utilities.

The Water Corporation secured a trading agreement with

Harvey Water in 2006 to permanently transfer 17.1 gigalitres

of water a year from the irrigation cooperative for public

water supply. Piping open channels, thereby reducing

leakage and evaporation, saved this water.

Harvey Water, the irrigation cooperative, has identifi ed that

there may be a further opportunity to trade 7 gigalitres of water

a year through more investment in on-farm water effi ciency.

Brunswick Dam

The Brunswick River is located 200 kilometres south of Perth,

near Brunswick Junction. There are several possible water

source development options ranging from a small dam to

a major large dam, resulting in supply of between 20 to 34

gigalitres of water per year.

The development of this dam would require additional

investment in water treatment due to water quality issues

in the catchment area. There are also signifi cant social and

environmental considerations including clearing of native

55

POTENTIAL SURFACE WATER SOURCES

Source option Cost Supply by 2030 Supply by 2060 Rainfall

dependence

Energy usage

Water trading - Harvey < $1 a kilolitre 7 gigalitres Not known High Low

Brunswick Dam $1 - 2 a kilolitre 30 gigalitres Not known High Low

Wellington Dam

• Groundwater

• Dam

• Water trading

< $1 /KL

$2-3 / KL

$2-3 / KL

10 gigalitres

14 gigalitres

16 gigalitres

Not known

Not known

Not known

Low

High

High

Low

Medium

Low

Water from the Kimberley

- pipeline

$9.70 a kilolitre 200 gigalitres 200 gigalitres High High

Water from the Kimberley

- canal

$20.50 a

kilolitre

200 gigalitres 200 gigalitres High High

Water from the Kimberley

- water bags

Not determined 200 gigalitres 200 gigalitres High High

Water from the Kimberley

- supertanker

$6.70 a kilolitre 200 gigalitres 200 gigalitres High High

vegetation, inundation of the river valley, impacts on private

landowners in the catchment area, impacts on fl ora and fauna

and possible loss of recreational and social values in the area.

These signifi cant issues are reasons why this resource has not

been developed to date.

Wellington Dam

Wellington Dam is an existing irrigation dam on the Collie

River located near the town of Collie in the South West of

the State. Harvey Water manages the irrigation district that

lies downstream. The dam is a popular recreational, fi shing

and boating destination.

Currently, the Collie and Muja power stations use Collie Coal

Basin groundwater.

Water resource issues in this area are complex due to the

connectivity of the surface and groundwater resources,

multiple users and the high salinity of water in Wellington

Dam. In addition, the dam yields are also declining due

to reduced rainfalls in recent years. Projections are for

continuing declining rainfalls due to drying climate, although

there may be some very wet years at times.

The State Government considered further development of

the Wellington Dam and Collie groundwater water resources

in 2007. The report ‘Water Source Options in the Collie-

Wellington Basin’ was released in May 2007.

The report noted that Wellington Dam and Collie Basin

groundwater are potential sources for public water supply.

The study examined a range of options, but recommended

more detailed work before decisions could be made. The

Department of Water is responsible for further investigations

of the recommendations made in the report.

The Water Corporation has examined three options to

develop these water resources for public water supply:

• short–term groundwater - there is a short term surplus

of groundwater currently set aside for mine dewatering.

This water is of relatively high quality and could be

accessed as a drinking water supply. The water could be

pumped into Stirling Dam and then on to the IWSS

water grid.

• long-term groundwater - if water could be supplied

to the power stations from Wellington Dam instead of

groundwater, the groundwater may become available for

long term public water supply. A 10 gigalitre a year

scheme could be developed using Stirling Dam to store

the water. This would require substantial upgrades to the

Stirling Dam infrastructure to connect it to the IWSS

water grid; and

• development of Wellington Dam for public water

supply - Wellington Dam could provide a 30 gigalitre

a year source for public drinking water supply. This may

require a desalination plant downstream of Wellington

Dam and a new trunk main to connect to the IWSS

(unless the water was retained for regional use). This

option is very complex and would require irrigators to

trade their current allocation to the public water supply.

There are also signifi cant catchment management issues

that would require resolution, as the Dam is a popular

recreational area.

Moving water from the Kimberley

For many years there has been community interest in

developing water resources in the far north of the State

for public water supply in Perth. Water resources in the

Kimberley are abundant and currently there is a signifi cant

amount of water from both the Ord and Fitzroy Rivers

fl owing to the ocean.

These resources have not been developed to date due to

access to adequate and cheaper surface water, groundwater

and more recently desalinated seawater closer to Perth. The

distance to transport water from the Ord River Dam (over

3,500 kilometres) is extremely high, six times the length of

the Perth – Kalgoorlie pipeline.

In 2004, the State Government appointed an independent

panel to evaluate the technical and fi nancial viability of

transporting water from the Kimberley region to service

inland communities and Perth. The comprehensive report

was released in 2006.

Four options were explored in detail to source 200 gigalitres

of water a year:

• a pipeline – from Fitzroy River to Perth;

• a canal – from Fitzroy River to Perth;

• towed water bags from the Ord Dam to Perth; and

• a super-tanker from the Ord Dam to Perth.

The Panel concluded that moving water from the Kimberley

in these quantities would have signifi cant social and

environmental impacts. In addition, energy consumption

for all options was extremely high. The lowest cost option,

transport via water tankers, produces 3 times as much

greenhouse gases as seawater desalination.

Importantly, the water has signifi cant cultural value to

Indigenous people and has signifi cant recreational and

tourist value. The pipeline and canal would both require

damming the Fitzroy River, which would have signifi cant

impacts on the local environment.

56

OPTIONS FOR OUR WATER FUTURE

All options are very costly. The unit cost of the cheapest

option, ocean transport by super- tankers is $6.70 per

kilolitre, more than 2.5 times the cost of desalination. The

most expensive option is the canal option, which has an

estimated unit cost of $20.50 per kilolitre.

These resources have been partially developed by the Ord

River irrigation scheme which supports irrigated horticulture

in Kununurra. Currently there is a State and Federal

Government taskforce, which is further examining the

development of these resources for local use.

Moving water from the North is not a water supply option

currently being considered by the Water Corporation.

GROUNDWATER SOURCES

Since the 1970’s groundwater resources of the sedimentary

Perth Basin have been developed to supply drinking water

to the metropolitan area and communities connected to the

IWSS water grid.

The Perth basin hugs the coast and extends North to the Mid

West and South to the Southern Ocean. It has the largest

fresh groundwater availability in Western Australia and

supports diverse ecosystems including wetlands, lakes and

caves. There are three major aquifers in the Perth basin: the

superfi cial (or shallow), the Leederville and the Yarragadee.

The superfi cial aquifer is connected to the surface and

can fl uctuate in response to annual rainfall. Water in the

confi ned Leederville and Yarragadee aquifers is separated

from each other and the superfi cial aquifer by an

impermeable layer called a confi ning bed. Water in these

aquifers may extend to depths of several thousand metres

and may include water recharged tens or thousands of years

ago, having less reliance on annual rainfall.

Groundwater from these aquifers supports public drinking

water supply, agriculture, mining, industry, public open

space and garden bores.

Currently about 50% of the IWSS water grid is supplied by

groundwater. Groundwater supplies are relatively low cost and

use small amounts of energy. Source protection areas maintain

these resources for drinking water supply. The aquifers

themselves provide storage of water from year to year.

There are a number of groundwater resources that have

been investigated to determine if they could be options for

our water future.

The following groundwater sources are currently unproven

and would require signifi cant further investigation, including

investigative drilling, to test the quality, quantity and viability

of the schemes. The Department of Water would need to

allocate water for public water supply to develop these

sources and they would require source protection.

The Karnup, Dandalup, Gingin, Jurien and North West

Coastal groundwater resources are relatively close to Perth

and preliminary estimates indicate they would cost $1.00 a

kilolitre to develop for local use. If the water requires piping

to distant areas within the IWSS water grid, signifi cant

integration costs will need to be added and may potentially

double these unit costs.

Most of these sources already have some private water

abstraction and are near private land holdings, nature

reserves or wetlands. Any development of these potential

groundwater resources requires further consultation. In

particular, advice from the Department of Water is required

as to whether there is any water available for public water

supply in these areas.

North West Coastal Groundwater

The North West Coastal groundwater scheme could be

located North of the existing Neerabup coastal groundwater

scheme, parallel to the coast. The groundwater is located

in the outer perimeter of the Gnangara Mound. There is

potentially a yield of 28 gigalitres a year (20 gigalitres by

2030) from the superfi cial aquifer which drains to the ocean.

The scheme would require treatment prior to distribution to

customers. This source is located close to future North West

corridor growth.

The Department of Water is currently fi nalising a Water

Management Plan for the Gnangara Mound, which

considers the reservation of groundwater from this area for

public water supply.

Consideration needs to be given to the social and

environmental impacts that may result from developing the

borefi eld in conjunction with private land developments.

The scheme includes some water from the superfi cial aquifer,

which may be adversely impacted by climate change.

Jandakot Groundwater

The Jandakot Mound is an existing water source for Perth.

The Water Corporation has abstracted about 7 gigalitres a

year on average, 5 gigalitres from the superfi cial aquifer and

2 gigalitres from the confi ned Leederville aquifer.

Works completed in 2007 have expanded the Jandakot

groundwater scheme to 10 gigalitres a year, with the

increase from the confi ned aquifer.

57

There is an opportunity to abstract a further 3 gigalitres a

year from the superfi cial aquifer. In addition to the expansion

of the borefi eld, this would require investment to increase

the capacity of the Jandakot water treatment plant.

Karnup - Dandalup Groundwater

The prospective Karnup - Dandalup groundwater scheme

is located 55 kilometres South East of Perth and has a

potential source yield of 20 gigalitres a year (10 gigalitres by

2030). This source, from both the superfi cial and confi ned

aquifers, is close to future growth in the South West

corridor.

The scheme could be similar in nature to other Perth

groundwater schemes and would most likely need treatment

prior to distribution to customers. The Department of Water

has not released a water management plan for this area.

Other major issues requiring resolution include the social

and environmental concerns of developing the borefi elds

amongst signifi cant wetlands and private land holdings. The

water may also be slightly salty, meaning it would require

blending with another higher quality water source to make it

suitable for drinking.

The scheme includes some water from the superfi cial aquifer,

which may be adversely impacted by climate change.

Gingin - Jurien Groundwater

The prospective Gingin – Jurien groundwater scheme is

located North of Moore River towards Badgingarra and has

a potential source yield of up to 30 gigalitres per year (20

gigalitres by 2030). Available water is from both superfi cial

and confi ned aquifers. The scheme could be similar in nature

to the Water Corporation’s other Northern groundwater

schemes and the water would most likely need full

treatment prior to distribution to customers.

There is signifi cant use of groundwater in this area for

irrigated horticulture. Any increase in water allocations

would require consideration by the Department of Water.

Competition for use, particularly with agriculture, is a major

consideration in relation to this source.

Environmental impacts must also be considered as all or part

of the borefi eld would be situated in nature reserves and

national parks.

South West Yarragadee Groundwater

The Water Corporation had a proposal to develop a 45

gigalitre a year groundwater scheme in this area to supply

the IWSS water grid. The scheme broadly consisted of

a borefi eld and water treatment plant near the town of

Jarrahwood, and a 110 kilometre buried pipeline to connect

the treatment plant to the IWSS water grid near Harvey.

POTENTIAL GROUNDWATER SOURCES

Source option Cost Supply by 2030 Supply by 2060 Rainfall

dependence

Energy usage

North West Coastal Less than $1 a

kilolitre

20 gigalitres Not known Medium Low

Jandakot expansion Less than $1 a

kilolitre

3 gigalitres Not known Medium Low

Karnup and Dandalup Less than $1 a

kilolitre

10 gigalitres Not known Medium Medium

Gingin - Jurien Less than $1 a

kilolitre

20 gigalitres Not known Medium Medium

South West Yarragadee $1 - $2 a

kilolitre

45 gigalitres Not known Medium Medium

58

OPTIONS FOR OUR WATER FUTURE

The Water Corporation conducted extensive investigations

and planning and applied for a water allocation from this

resource. An Environmental Review and Management Plan

was submitted to the Environmental Protection Authority for

approval in late 2005.

The Water Corporation has formally withdrawn the

application to use the source.

The Department of Water is currently fi nalising a

management plan for this groundwater system that includes

reservation of water for public water supply, primarily for

regional water demand.

OTHER OPTIONS

The Water Corporation is exploring catchment management

and cloud seeding to determine if they are options for

Perth’s water future. They are both rainfall dependent.

Catchment management

Forest or catchment management includes various

techniques to improve the state of the forest and conserve

the environment. Catchment thinning is one such technique

that has been used in the past to improve the environment

and increase streamfl ows.

In 2002, the need for a better understanding of the interaction

between water, land and biodiversity in our forested

catchments was identifi ed to provide informed decisions on

their future management. To address this need the Water

Corporation prepared a proposal to undertake extensive

research in the Wungong Drinking Water Catchment.

The Wungong Catchment is a drinking water catchment

60 kilometres South East of Perth. The catchment has been

previously logged and mined for bauxite. It lies within a high

rainfall zone and is considered a degraded regrowth forest

consisting of mainly jarrah and marri trees.

A 12-year trial is currently underway in the Wungong

Catchment to observe how removing certain types of trees

affects streamfl ows and biodiversity in the forest. This tree

removal process is known as forest or catchment thinning.

The Water Corporation has partnered with environmental

agencies, universities and research institutions to implement

an extensive research and monitoring program. The trial will

be assessed regularly to incorporate adaptive management

responses.

An extension to include other forested catchments would

be considered only if the community and Government are

comfortable with the fi ndings.

If similar forest management is applied to other metropolitan

catchments in the high rainfall zone there is a potential

to yield an additional 25 gigalitres of water per year by

2030, based on current rainfall. Catchment management is

dependent on rainfall.

Cloud seeding

Cloud seeding attempts to artifi cially generate rain by

implanting clouds with particles such as silver iodide crystals.

This is usually carried out by sprinkling the particles from

above by plane, which is fi tted with silver iodide burners

mounted under each wing. Using weather forecasting

techniques, suitable clouds are identifi ed based on the

location of the target area and the prevailing winds.

A seeded cloud will take 30 minutes to precipitate and

seeding areas are chosen upwind of the target. Clouds

moving over Perth could be seeded which would cause them

to release rain over the catchment areas thereby increasing

streamfl ow to the dams.

In 2007, the Water Corporation commissioned the Bureau

of Meteorology to undertake a study into the effectiveness

of cloud seeding in Perth. The study concluded that cloud

seeding should not be seen as a short-term response to

drought but rather as a longer-term water management

tool. It recommended further fi eld-testing and evaluation.

Further trials over a number of years would need to be

undertaken by the State Government to consider impacts on

other sectors including agriculture and the environment.

The Water Corporation is not currently considering cloud

seeding as a future source option.

MEETING GROWING DEMAND FOR WASTEWATER SERVICES

Our wastewater systems are built and upgraded to treat large

volumes of wastewater well into the future. In most cases, our

wastewater treatments systems won’t reach their capacity until

more than 100 years after the original date of commissioning.

That’s why thinking 50 years ahead is so important to the

Water Corporation and our customers.

Wastewater systems are constructed in stages as capacity is

progressively increased with growth in fl ows. This has many

advantages including:

• deferral of capital funding;

• less impact on adjacent land uses early in plant

development;

• lower operating costs;

59

• integration of technological advances over the life of a

plant; and

• progressive addition of recycled water facilities as

demand arises.

For example, the Woodman Point Wastewater Treatment

Plant was originally commissioned in 1966, which included

one treatment plant and an ocean outlet. In 1984, a new

larger 45 gigalitre a year primary treatment plant was

added and a new outlet into the open waters of the Sepia

Depression was installed. In 2002, further investment

resulted in the commissioning of more advanced secondary

treatment which helped to facilitate water recycling to the

Kwinana Industrial Area and reduced the level of nutrients

being discharged into the ocean.

Similarly, both Subiaco and Beenyup plants have been

upgraded to enable more wastewater to be treated and to

improve odour management.

Decisions to increase system capacity and levels of treatment

in the Perth and Mandurah wastewater systems are

considered in two parts:

• works already scheduled to upgrade the systems; and

• further works required to accommodate additional fl ows

forecast to 2060.

Scheduled wastewater upgrades

As noted earlier, the current fl ows and plant capacity of

existing wastewater treatment plants in Perth and Mandurah

are nearly matched which signifi es that treatment plant

upgrades are required.

In addition, new wastewater treatment plants will

be constructed at Alkimos and East Rockingham to

accommodate growth in the North West coastal and

Southern corridors of Perth. These plants are at advanced

stages of planning. Alkimos is due to be commissioned in

2011 and East Rockingham by 2015.

Major capital works of over $2 billion are scheduled for

delivery over the next 10 years to increase the capacity of

the existing wastewater systems and to build the two new

treatment plants.

The new scheme at Alkimos will incorporate gravity to

transport the wastewater to the treatment plant in the long

term. In the short to medium term, pumping stations and

pressure mains will move the wastewater. The ocean outlet

will initially have capacity to take up to half the long-term

volumes of wastewater when water-recycling opportunities

are not available.

The Beenyup, Subiaco and Woodman Point wastewater

treatment plants are scheduled to have increased capacity

and more investment in odour reductions.

The new plant for East Rockingham is designed for the same

medium and long term sewer confi guration as Alkimos. The

plant will progressively duplicate the existing ocean outlet

from East Rockingham to Point Peron.

New works required to meet long term fl ow forecasts

There will be a further need to increase wastewater system

capacity to service projected fl ows after 2030.

One of the most important factors is to understand where

future development will occur so that we can plan for future

upgrades to our wastewater systems.

Based on Western Australian Planning Commission

population projections and distribution, we are planning for

signifi cant increased housing density near Perth. This means

that the existing wastewater systems at Subiaco, Beenyup

and Woodman Point may require even further expansion.

There is also further growth forecast in the Northern

and Southern land development corridors. As a result,

the planned Alkimos and East Rockingham systems will

eventually need to be expanded beyond their initial capacity.

POTENTIAL WATER FROM OTHER OPTIONS

Source option Cost Supply by 2030 Supply by 2060 Rainfall

dependence

Energy usage

Catchment management Less than $1 a

kilolitre

25 gigalitres

a year

Not known High Low

Cloud seeding Not costed Not known Not known High Low

60

OPTIONS FOR OUR WATER FUTURE

Expanding existing treatment plants in built up areas or

building new wastewater treatment plants can be very

diffi cult. We have encountered substantial obstacles in

securing land for new treatment plants due to pressure to

develop land for residences. This has been our experience

even when the land for treatment plants has been secured

several decades before the plant is required.

Planning to consider wastewater expansion after 2020 is

currently being undertaken.

Consolidating wastewater treatment plant capacity

The consolidation of wastewater systems can improve overall

effi ciency and operations. It can also lead to alternative land

uses in areas adjacent to decommissioned plants.

Opportunities to recycle water can still be accessed through

sewer mining or transport of recycled water to demand centres.

The existing Yanchep and Two Rocks wastewater treatment

plants are currently serving the proposed Alkimos

wastewater system. It is proposed that these plants be

decommissioned on completion of the Alkimos plant.

The Point Peron and Kwinana plants are currently serving the

proposed East Rockingham wastewater system. The Kwinana

plant is expected to be retained due to opportunities to

recycle to the Kwinana Industrial Area, while the Point

Peron plant is expected to be decommissioned when East

Rockingham is fully operational.

Review of Mandurah wastewater treatment plants

There are four wastewater treatment schemes in the

Mandurah vicinity:

• Gordon Road;

• Caddadup;

• Halls Head; and

• Pinjarra.

The fi rst three currently discharge treated wastewater to

groundwater where it is available for recycling, mainly

for irrigating public open space. All wastewater from the

Pinjarra plant is recycled for industrial use.

These plants are all nearing their capacity. In addition, the

Mandurah area is growing rapidly and signifi cant increases in

wastewater fl ows are forecast. There are several options that

are being considered to manage growth in Mandurah to 2060:

• continue to expand existing plants;

• consolidate all 4 plants onto a new treatment plant site;

or

• a combination of the above with some expansion of

existing plants and some consolidation to a new plant.

Planning, including the identifi cation and evaluation of options,

is underway for all Mandurah wastewater treatment plants.

61

WASTEWATER TREATMENT PLANT EXPANSIONS AND NEW WASTEWATER TREATMENT PLANTS TO BE BUILT BY 2020

Schemes

(north to south)

Current

capacity

Current

fl ows

Capacity by

2020

Timing Nature of works

Gigalitres a year

Two Rocks 0.03 0.02 0 2012 Decommission after

Alkimos WWTP is built

Yanchep 0.2 0.1 0 2012 Decommission after

Alkimos WWTP is built

Alkimos 0 0 7 2008-2011 New plant

Bullsbrook 0.13 0.07 0.13 No works

Beenyup 43 43 55 2008-2013 Expand plant capacity

Odour reduction

Subiaco 22 22 27 2013-2017 Expand plant capacity

Mundaring 0.04 0.04 0.09 2010-2012 Expand plant capacity

Woodman Point 44 44 66 2008-2017 Expand plant capacity

Odour reduction

East Rockingham 0 0 15 2011-2015 New plant

Kwinana 1.5 1.2 4.4 2008-2010 Expand plant capacity

Point Peron 7.3 5.4 0 Decommission after East

Rockingham WWTP is built

Gordon Rd (Mandurah) 2.9 2.4 4.4 2008-2009 Expand plant capacity

Sludge dewatering works

Halls Head 1.1 1.0 2.1 2008 Expand plant capacity

Caddadup 0.4 0.4 0.7 2008 Expand plant capacity

Increase level of treatment

Pinjarra 0.6 0.3 0.6 No works

Total fl ows 123 120 182

Forecast fl ows at 2020 155

Forecast fl ows at 2030 179

Forecast fl ows at 2060 237

62

TOWARDS

IMPLEMENTATION

It is anticipated that a Water Forever Directions paper will be

released in late 2008. This document will propose how water

services could be delivered for the next 50 years in response

to community feedback received on this Options Paper.

The community will be provided with the opportunity to

comment on the draft plan, Water Forever Directions, for a

minimum of 10 weeks.

REGULATORY APPROVALS

The Water Corporation is required to seek a range of

approvals from Government to conduct our business. These

are outlined in the table below.

The Water Corporation has engaged with these stakeholders

from the beginning of Water Forever.

Water Forever Directions will outline key milestones to seek

the formal approvals required to implement the plan.

SUSTAINABILITY ASSESSMENT

As outlined, the Water Corporation applies sustainability

criteria as part of our business operations. This means that

we evaluate all future options by undertaking a thorough

consideration of social, environmental and economic

matters.

The information sheets developed to support this Options

Paper include a table where sustainability issues have been

identifi ed. In some instances, the impacts of an option are

positive or benefi cial while other impacts are negative or

require mitigation.

The Water Forever Directions paper will outline our proposed

approach to ensure that the fi nal Water Forever plan

supports a sustainable water future for all.

ENERGY REQUIREMENTS

Historically, the Water Corporation and customers have

benefi ted from relatively low energy solutions. The use of

surface water and groundwater sources and gravity to move

water and wastewater around the system has helped reduce

our energy footprint.

Nonetheless, the Water Corporation is a signifi cant energy

user. The Conserve section of this paper highlights existing

energy use and strategies to reduce our greenhouse gas

emissions and demand.

GOVERNMENT AGENCY RESPONSIBILITIES

Agency Responsibility

Department of Environment and Conservation Conservation reserves

Biodiversity

Wetlands and waterways

Wastewater discharges

Department of Health Public health

Compliance with drinking water quality guidelines

Department of Water Water resource and industry policy

Water resource management, investigation, monitoring

Water allocation

Water use effi ciency and recycling

Customer dispute resolution

Economic Regulation Authority Inquiries into water pricing and performance

Operating licence and customer charter

Environmental Protection Authority Environmental assessment and protection

Western Australian Planning Commission Land use planning and land development matters

64

OPTIONS FOR OUR WATER FUTURE 65

Water services delivery in the future is expected to be much

more energy intensive. This is due to a number of factors:

• increasing reliance on desalination, an energy intensive

source;

• increasing levels of wastewater treatment, to support

more recycling;

• longer distances to transport water and wastewater; and

• the need for more pumping due to increased volumes of

water and wastewater.

Current energy policy and direction is highly uncertain at

global, National and State levels due to the rapid impact

of climate change and the search for new technologies,

sources, market and regulatory mechanisms. Planning

for energy impacts for the Water Corporation and our

customers is very challenging as a result.

Noting these limitations, Water Forever will estimate the

increased energy demands expected to support water

service delivery in the fi rst planning horizon, to 2020. It will

also propose strategies to manage demand and emissions

through this period.

PRICING IMPACTS

In Australia, the aim is for water prices to be cost refl ective.

This helps to ensure ongoing investment in water services

and send price signals to users that may infl uence demand.

Pricing for water services in Western Australia follows this

principle. Prices for wastewater and drainage services are

based on the improved value of land, seeking to ensure

these services remain affordable.

The Government of Western Australia sets prices in Cabinet,

generally with advice from the Economic Regulation

Authority and the Department of Water.

Concessions are provided to seniors and pensioners to

help maintain the affordability of these essential services.

Recognising the higher per capita cost of services in regional

areas, the Government also provides subsidies for water

services in country towns, including Mandurah.

Currently, the combined price of water and wastewater

services to Perth is comparable with other states.

As in other parts of Australia however, there is an

expectation that signifi cant investment in water services

will be required through to 2060 to meet the needs of our

growing city. It is likely that prices will rise as a result.

There are some factors that are expected to favourably

infl uence these prices (keep them low):

• densely populated urban areas benefi t from economies

of scale;

• technological innovations may reduce capital and

operating costs; and

• for the next 10 years, Perth will benefi t from a well

maintained, relatively young infrastructure base.

However, other factors are expected to push water prices

up. These include:

• price increases required to fund investment to date;

• an increasing reliance on technology to source and treat

water that is more expensive than traditional sources and

wastewater treatment options;

• a continued and increasing competition for key resources

including land, contractors, raw materials and

appropriate energy sources;

• a growing need to maintain ageing infrastructure,

particularly after 2020; and

• increasing regulatory standards.

Water Forever will outline the estimated impact on costs

for water, wastewater and drainage for the fi rst 10-year

investment horizon to 2020.

Consideration will be given to how tariffs could be

structured to minimise price shocks and maximise

affordability, while noting that the State Government makes

the fi nal decision in this regard.

Price impacts for future years can be estimated as greater

certainty over the actual timing and nature of the investment

program is known. This can be monitored and reported on,

after the release of the fi nal plan.

OPPORTUNITIES FOR PRIVATE SECTOR PARTICIPATION

Competition plays an important role in the delivery of water

services in Western Australia. Customers obtain the benefi ts

of the Water Corporation’s effi ciency in obtaining water on

their behalf.

The Water Corporation has successfully worked with the

private sector since our inception. Today, the private sector

directly provides over 90% of the Water Corporation’s

capital projects and 50% of our operating programs through

processes that involve competitive selection.

Along the way, there have been many innovations to

improve competitive procurement processes. These are

achieved by balancing the need to maintain competitive

tenders, attracting participation, reducing the cost of

tendering and continuous learning from project to project.

Currently, the Water Corporation is seeking to establish new

ways to work with the private sector. These could include

the private sector owning new water and wastewater assets.

It is generally accepted that the ownership of network assets

(trunk mains and distribution pipes) is a natural monopoly

and will continue to be owned by the Water Corporation.

However new water sources, wastewater treatment and

disposal assets could be owned by the private sector.

Water Forever will identify future assets expected to be best

suited to private ownership and other ways for the sector to

become more involved in water service delivery in Western

Australia.

In the meantime, private interests are invited to suggest

further options for long term planning that will help us to

secure our water future.

RESEARCH AND INNOVATION

Advances in technology have contributed to the continuing

development of the urban water industry and are now

making climate independent sources like desalination and

recycled water more cost effective. More specifi cally it’s the

technological processes like micro and ultra fi ltration and

reverse osmosis, coupled with membrane improvements, which

have reduced the costs of these technologies in recent years.

According to CSIRO’s ‘Unchartered Waters’ report, key

drivers for innovation in urban water management include

reducing stormwater pollutant impacts and the recycling of

wastewater. Added to this is the need for better monitoring

and control technologies.

Water Forever will seek to identify major areas for investment

in research and knowledge. These can form the basis for

further partnerships with academic and scientifi c organisations.

COMMUNITY EDUCATION

The Water Corporation actively supports community

education through our Waterwise programs for schools,

businesses, irrigators, garden centres and plumbers.

Over 300 schools are engaged in the Waterwise Schools

Program, which integrates a broad range of concepts to

support sustainable water services into the curriculum. This

program supports education from kindergarten to Year 12.

Water Forever will outline proposed community education

activities as part of the implementation process. At this time,

we are developing a number of strategic partnerships to

allow us to work with the community to raise awareness of

water matters.

66

OPTIONS FOR OUR WATER FUTURE 67

WAYS TO HAVE YOUR SAY

ON WATER FOREVER

Water Forever is the Water Corporation’s 50 year plan to

deliver water services to Perth and surrounding areas.

There are a number of ways you can have your say on our

50 year plan.

1. Visit www.watercorporation.com.au/waterforever to

register and fi ll out the online feedback form.

2. Write to us at:

Water Forever

Water Corporation

Locked Bag 2

Osborne Park Delivery Centre

WA 6916.

Public submissions close on 30 June 2008.

68

INFORMATION SHEETS

Alkimos Wastewater Treatment Plant

Alternative Water Supplies

Beenyup Wastewater Treatment Plant

Brunswick Dam

Catchment Management

Cloud Seeding

East Rockingham Wastewater Treatment Plant

Esperance Kalgoorlie Desalination

Garden Bores

Gingin Groundwater

Gnangara Groundwater

Greywater Reuse And Recycling

Groundwater Salinity In Rural Towns

Groundwater Schemes – An Overview

Integrated Resource Planning

Integrated Urban Water Management

Jandakot Groundwater

Karnup & Dandalup Groundwater

Mandurah Wastewater Treatment Plants

Mundaring Weir

North Dandalup Dam

North West Coastal Groundwater

Ocean Discharge Of Treated Wastewater

Permanent Water Effi ciency Measures

Rainwater Tanks

Recycling – Agriculture

Recycling - Groundwater Replenishment

Recycling – Industry

Recycling – Public Open Space

Seawater Desalination

Serpentine Dam

South Dandalup Dam

Stormwater Recycling

Subiaco Wastewater Treatment Plant

The Water Grid

Wastewater Odours

Water Effi ciency

Water From The North

Water Restrictions

Water Trading

Waterwise Businesses

Waterwise Homes Gardens Communities

Waterwise Schools

Wellington Dam

Woodman Pt Wastewater Treatment Plant

These information sheets can be downloaded from

www.watercorporation.com.au/waterforever.

Disclaimer

The Water Corporation is committed to quality service to

customers, including the provision of reliable data in this

document. This Options Paper is designed to promote

discussion on a range of water futures. It does not represent

the policy of the Water Corporation or the Government of

Western Australia. Changes in circumstances after publication

may impact the quality of information.

Data contained in this publication is current as at the date of

publication.

Copies are available by phoning 13 10 39 or visiting

www.watercorporation.com.au/waterforever

OPTIONS FOR OUR WATER FUTURE

The text for this document is printed on 100% recycled

paper, manufactured to ISO14001 environmental standards.

The paper is Australian made and produced from 100%

recycled fi bre, helping to redirect waste from landfi ll sites

around Australia. The inks used to print this report are

vegetable based.

© Water Corporation

ISBN 174 043 456 0

This information is available in alternative formats on request.