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BLUE M

OU

NTA

INS SYSTEM

DAMS OF GREATER SYDNEY AND SURROUNDS

Blue Mountains

Sydney’s drinking water is collected from five catchment areas, occupying 16,000 square kilometres. Water is stored in 21 dams, holding over 2.5 million megalitres of water.

The Blue Mountains System comprises three small catchment areas feeding six dams, which provide water for about 41,000 people living in the Blue Mountains region.

< BLUE MOUNTAINS CATCHMENT AREA

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Introducing WaterNSW

WaterNSW is Australia’s largest water supplier. We provide two-thirds of the water used in NSW and develop infrastructure solutions for water supply security and reliability.

We operate and maintain 42 large dams and we deliver water for agriculture and drinking water supply customers. WaterNSW also protects the health of Sydney’s drinking water catchment to ensure highest quality drinking water is consistently available.

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Blue Mountains Catchments

Cooma

Sydney’s drinking water catchments

Pumping station

Canals and pipelines

Prospect WaterFiltration Plant

Upp

er C

anal

Pipelines

Braidwood

Canberra

Shoa

lhav

en River

Goulburn

Nowra

Wollongong

Lithgow

Sydney

Wollondilly River

Bendeela PondageLake Yarrunga

Nattai River

Nepean River Woro

nora River

Haw

kesb

ury R

iverCoxs River

ProspectReservoir

WarragambaDam

WoronoraDam

TallowaDam

Fitzroy FallsReservoir

WoodfordDam

Greaves CreekDam

MedlowDam

CascadeDams

CordeauxDam

Broughtons Pass Weir

Pheasants Nest Weir

AvonDam

NepeanDam Cataract

Dam

Bowral

WingecarribeeReservoir

Katoomba

Kowm

ung Rive

r

LakeBurragorang

Wingecarribee River

Dam

Crookwell

Sydney’s drinking water catchments

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A catchment is an area where water is collected by the natural landscape. In a catchment, all rain and run–off water eventually flows to a creek, river, lake or ocean, or into the groundwater system.

Natural and human systems, such as rivers, bushland, farms, industry, homes, plants, animals and people can exist alongside one another in a catchment.

The catchments

BLUE MOUNTAINS CATCHMENT

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WaterNSW helps protect five catchment areas, which provide water to greater Sydney and local communities.

They are:• Warragamba Catchment• Upper Nepean Catchment• Woronora Catchment• Shoalhaven Catchment• Blue Mountains Catchment

The catchments occupy about 16,000 square kilometres in total. They extend from north of Lithgow and Blackheath in the upper Blue Mountains, south to the source of the Shoalhaven River near Cooma, and from Woronora in the east to the source of the Wollondilly River near Crookwell.

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The Blue Mountains catchment comprises three smaller catchments: Katoomba (5 square kilometres) Woodford (9.8 square kilometres) and Blackheath (7.2 square kilometres).

A total of six dams are located within these three catchments.

Katoomba Catchment: the Lower, Middle and Upper Cascade dams on Cascade Creek Blackheath Catchment: Greaves Creek Dam on Greaves Creek and Lake Medlow Dam on Adams Creek Woodford Catchment: the Woodford Dam at the junction of Bulls Creek and Woodford Creek

Together these dams supply water to about 41,000 people, from Mt Victoria to Springwood. Residents living between Mt Victoria and Medlow Bath depend solely on the dams in the Blackheath catchment for their water supply.

Blue Mountains Catchment

The Katoomba and Blackheath catchments are classified as Special Areas, so access is restricted to protect water quality. Woodford Dam is not currently used for water supply and the Blue Mountains National Park in the previously restricted Woodford Catchment area is now open for limited recreational access including walking and cycling. There is still no access to the dam wall or Lake Woodford. These are protected as possible future water supply options for the Blue Mountains.

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When Blaxland, Wentworth and Lawson reached present–day Hazelbrook on 20 May 1813 they achieved the first successful crossing over the Blue Mountains. The following year Governor Macquarie commissioned a cart road to the west and soon staging posts were built where permanent water was found.

Supplying water to the Blue Mountains

The re–routing of the road and the introduction of the rail link to Bathurst marked the end of these camps. Between 1867 and 1876 the railway was extended from Penrith to Bathurst.However inadequate water supplies for the steam locomotives led to the damming of Bulls Creek near Woodford in 1884.

The construction of the six dams that serve the Blue Mountains region spanned many years – from the construction of Middle Cascade Dam in 1905 to the building of Greaves Creek Dam in 1942.

Ownership of these dams was transferred from the Blue Mountains City Council to the then Metropolitan Water Sewerage and Drainage Board in 1980 and are now part of WaterNSW’s assets.

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The three dams on Cascade Creek, supplemented by water from Greaves Creek Dam and the Fish River Scheme, provide the bulk water supply storage for Sydney Water’s Cascade filtration plant. This plant provides filtered water for the communities from Springwood to Mount Victoria. During drought water from Warragamba Dam is available for supply, but only for communities as far west as Wentworth Falls.

The first dam, Middle Cascade Dam, was built in 1908 and upgraded in 1915. It is a concrete arch dam.

Height: 15 metres Length: 105 metres Total capacity: 160 megalitres Catchment area: 2.1 square kilometres

Cascade dams

SYDNEY WATER’S CASCADE FILTRATION PLANT

MIDDLE CASCADE DAM

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Lower Cascade Dam was completed in 1926. It lies downstream of the other Cascade dams. It is an earthfill embankment dam with a central concrete core.

Height: 26 metres Length: 128 metres Total capacity: 320 megalitres Catchment area: 3.2 square kilometres

Upper Cascade Dam is another earthfill embankment dam with a central concrete core. It was built in 1938.

Height: 30 metres Length: 247 metres Total capacity: 1,700 megalitres Catchment area: 1.7 square kilometres

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In 1916 the Public Works Department proposed a dam on the junction of Woodford Creek and Bulls Creek. Designed in 1927 and built in 1928 by the NSW Railways, Woodford Creek Dam is a concrete arch structure.

The dam was used to supply water, treated at Linden water filtration plant (WFP), to communities from Linden to Emu Plains. Additional water was supplied to this area from Warragamba Dam when necessary. Sydney Water no longer draws water from Woodford Creek Dam, and the region is now supplied from Cascade WFP or Orchard Hills WFP.

Height: 16 metres Length: 114 metres Catchment area: 9.8 square kilometres

Woodford Creek Dam

> WOODFORD CREEK DAM

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Water from Lake Medlow and Greaves Creek dams is pumped to Cascades dams to supplement supply.

Lake Medlow Dam, initially known as Adams Creek Dam, was constructed in 1907 on Adams Creek. Used to top–up the Greaves Creek Dam in emergencies, it is the first concrete thin arch high stress dam built in NSW. With a thickness of only 274cm at the bottom and 106cm at the top, it is reputedly one of the thinnest dams in the world. The Institution of Engineers Australia placed an ‘Historic Engineer Marker’ on the dam on 24 July 1994. The National Trust and Blue Mountains City Council have registered the dam on their heritage list.

Height: 20 metres Length: 38 metres Total capacity: 300 megalitres Catchment area: 4.8 square kilometres

Lake Medlow and Greaves Creek dams

LAKE MEDLOW DAM

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A concrete arch dam, Greaves Creek Dam was constructed in 1942 and upgraded in 1993. The dam supplies water to Greaves Creek filtration plant, which in turn supplies the communities from Medlow Bath to Mt Victoria. It can also supply water to top–up Cascade Dams.

Height: 19 metres Length: 67metres Total capacity: 310 megalitres Catchment area: 7.4 square kilometres

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Pride and workmanship

A time capsule is believed to be hidden in the centre line of the wall at the top water level of Greaves Creek Dam. Placed by the workers on 22 January 1941, the capsule contains a parchment listing all their names. It includes this dedication:

“All (the workers) are happy in the knowledge that the materials and their combination in the concrete are sound.

All have a deep personal satisfaction that the wall is true to shape, that the concrete is well and truly placed, and that the whole of the construction to the smallest detail has been carried out in the most faithful manner.

All are confident that, because of their loyal attention to their duties, the wall will remain stable and be durable and will impound the rains which fall on the catchment, for centuries to come.

Thus by the efforts of all will future generations be served.”

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As well as providing water to supply the Blue Mountains region, WaterNSW also sources water from the Fish River Scheme, which originates at Oberon.

The Fish River Scheme comprises a dam and a weir for raw water supply, as well as reservoirs, 236 kilometres of pipelines, four pumping stations, a tunnel, chlorinator, and clarification plants for water transfer and reticulation to customers.

Water can be used either to replenish the Upper Cascades Dam, or go directly to Sydney Water’s filtration plant at Cascades Dam. This gives WaterNSW and Sydney Water maximum flexibility in sourcing the best quality water, as well as providing a supplementary water supply during periods of low rainfall or maintenance activities. This scheme also provides water to three other major customers.

Fish River Scheme

Ensuring dam safety

It is essential that all WaterNSW dams meet the requirements of the NSW Dams Safety Committee (DSC) under the NSW Dams Safety Act (1978). The DSC, the State’s regulator for dam safety, develops and implements policies and procedures for effective dam safety management in order to protect life, property and the environment from dam failures.

To ensure compliance with its operating licence, WaterNSW has adopted a structured program of surveillance and monitoring that complies with the requirements of the DSC and national and international best practice.

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In Greater Sydney’s drinking water catchment, WaterNSW conducts extensive routine water quality and quantity monitoring in the catchments, storages and in–flows to water filtration plants. Monitoring provides information to enable the best quality water to be drawn–off into the supply system, and to identify areas requiring special catchment management attention. WaterNSW also conducts regular testing at several locations for the presence of the protozoan parasites Giardia and Cryptosporidium in the water. Information collected from WaterNSW’s monitoring programs is used for public health reporting and assessment.

Monitoring water quality

Maintaining good water quality in the catchmentWaterNSW works with government, industry and the community to promote good water quality and healthy, sustainable catchments.

Extensive research is carried out by WaterNSW to help understand the catchment environment. WaterNSW also plays an important role in ensuring that proposed land use and development is compatible with preserving water quality.

Field staff undertake a range of on–ground activities in the catchments, such as pest control, fire control, erosion control and repair, regulating access, containing spills and weed control. In the Special Areas (land closest to the storages) these activities are jointly managed by the National Parks and Wildlife Service (Office of Environment and Heritage) and WaterNSW.

Many successful projects are also undertaken jointly with landholders and community groups including riverbank stabilisation, willow removal, revegetation and riverbank fencing.

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Did you know?

During World War II the Blue Mountains dams were given extra importance as a water supply in the event of a mass evacuation of Sydney residents to the Blue Mountains.

The Blue Mountains National Park and World Heritage Area adjoins Blackheath and Woodford catchments and is close to the Katoomba catchment.

As a result, the catchments have considerable ecological value and provide habitat to a wide variety of rare and threatened plant and animal species. Threatened fauna include the Tiger Quoll, Blue Mountains Swamp Skink, Glossy Black Cockatoo, Powerful Owl, Sooty Owl, Blue Mountains Tree Frog and Banjo Frog.

As the home of the Darug and Gundungarra people for at least 17,000 years, the Blue Mountains are rich in Aboriginal heritage.

Water collected in the Blue Mountains catchments shows naturally high levels of manganese and iron due to the chemical composition of the local sandstone.

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How to get there

Walls Cave: The walk starts at Walls Cave Road, off Evans Lookout Road in Blackheath.

The Transit of Venus: The track head is on Woodbury Street at Woodford, off the Great Western Highway.

Recreation in the Blue Mountains catchments

Because the Blue Mountains catchments are recognised as Special Areas, all access – on foot or by vehicle – is prohibited to protect water quality.

The exceptions are walking on two defined tracks in the Blue Mountains catchments: Walls Cave walking track in the Blackheath catchment and the Transit of Venus walking track, which provides access to Hazel, Mabel and Edith Falls, in the Woodford catchment.

Limited recreational access including walking and cycling is also now permitted to the Blue Mountains National Park in the previously restricted Woodford Catchment area. There is still no access to the dam wall or Lake Woodford.

Blue Mountains facilities

Walking tracks

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The three small catchments of the Blue Mountains are classified as Special Areas.

In total, Special Areas cover about 3,700 square kilometres of land surrounding WaterNSW water storages.

The Special Areas protect our water supply because they act as a buffer zone, helping to stop nutrients and other substances that could affect the quality of water entering the storages.

WaterNSW and the National Parks and Wildlife Service (Office of Environment and Heritage) jointly manage the Special Areas, in accordance with the Special Areas Strategic Plan of Management.

This long–term plan aims to provide high quality water in the storages, ensure ecosystem integrity, and improve the environmental quality of the catchment areas.

Why Special Areas are protected

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Public access to parts of the Special Areas is restricted to protect water quality. This benefits the community by:

• ensuring we have safe, clean water• protecting large areas of bushland and

plant and animal habitats• protecting threatened plants and animal

species• preserving evidence of Aboriginal

occupation dating back many thousands of years, and

• preserving evidence of European exploration, early settlement, and phases of development such as forestry, mining and dam building.

Restrictions and controls are placed on landuse, development and access within SpecialAreas. Activities such as swimming, fishing,boating and camping are prohibited, unlessotherwise specified.

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How you can help keep our catchments healthy

Saving water

Water is a precious resource. Each of us has a responsibility to reduce the amount of water we use – no matter where we live.

By reducing the amount of water we all use, we reduce the need to build expensive new water supply infrastructure such as dams, reservoirs and pipelines.

Reducing the amount of water we all use can also help make more water available for environmental flows, which protect the health of the rivers downstream of the dams.

WaterNSW also recognises the need to adopt exemplary practices in managing our own business. Minimising leaks in pipelines and fitting water saving appliances and devices are just some of the ways WaterNSW is reducing the amount of water we use.

Water saving tipsFor great water savings ideas visit www.waternsw.com.au/water-quality/education/learn/using-less-water.

In the catchmentsPeople living and working in the catchments areas play a special role in keeping our catchments healthy. Some of the ways people in the catchments help include:

• using chemicals efficiently and carefully• controlling weeds and pests• retaining and planting vegetation to

prevent soil loss• protecting stream bank vegetation to

provide a buffer against pollution• managing on–site sewage systems

effectively• encouraging and developing improved

sewage and stormwater management systems

• preventing bushfires• reporting spills.

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Sydney’s watersupply system

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Contacting WaterNSW

Level 4, 2-6 Station Street, Penrith 2750 PO Box 323, Penrith NSW 2751

Phone 1300 662 077 Office hours 8.30am to 5pm Monday to Friday Website www.waternsw.com.au Email customer.helpdesk@waternsw.com.au

Visitor information

Warragamba Dam Visitor CentrePhone + 61 2 4774 4433Hours 10am to 4pm daily except Christmas Day and Good Friday

Other dams, reservoirs and camping groundsPhone 1300 662 077Hours 8.30am to 5pm Monday to Friday

Emergency reporting (24 hours)

Fires, chemical spills Phone: 1800 061 069

Important

Information contained in this brochure may change after the date of printing. The WaterNSW accepts no responsibility or liability for any loss or inconvenience incurred as a result of reliance upon information printed in this brochure. For the most up–to–date information on WaterNSW dams and recreational facilities, call 1300 662 077 or visit our website at www.waternsw.com.au

Acknowledgement

WaterNSW acknowledges the assistance of the Sydney Water Corporation and WaterNSW Historical Research and Archives Facility in researching and supplying historical images for use in this publication.

Photography credits

Adam Hollingworth ©WaterNSWTVU ©WaterNSW

ISBN 1 876951 12 5 Reprinted December 2015