W ARR AG AMBA

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DAMS OF GREATER AND SURROUNDS The Sydney Catchment Authority (SCA) manages a total of 21 storage , holding over 2.5 million megalitres of water. Water for Warragamba these storages is collected from five catchment areas, occupying 16,000 square kilometres. The Warragamba Catchment supplies Warragamba , Sydney’s most important source of water. Completed in 1960, holds about four times more water than Sydney Harbour and accounts for about 80 per cent of the region’s available water supply.

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DAMS OF GREATER SYDNEY AND SURROUNDS The Sydney Catchment Authority (SCA) manages a total of 21 storage dams, holding over 2.5 million megalitres of water. Water for Warragamba these storages is collected from five catchment areas, occupying 16,000 square kilometres. The Warragamba Catchment supplies Warragamba Dam, Sydney’s most important source of water. Completed in 1960, Warragamba Dam holds about four times more water than Sydney Harbour and accounts for about 80 per cent of the region’s available water supply.

A catchment is an area where water is The Sydney Catchment Authority (SCA) collected by the natural landscape. In a protects five catchment areas, which provide catchment, all rain and run–off water water to greater Sydney and local communities. eventually flows to a creek, , lake They are: or ocean, or into the groundwater system. • Warragamba Catchment Natural and human systems, such as , • Upper Nepean Catchment bushland, farms, industry, homes, plants, • Woronora Catchment animals and people can exist alongside one • Shoalhaven Catchment another in a 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 near Cooma, and from Woronora in the east to the source of the > WARRAGAMBA CATCHMENT near Crookwell. Warragamba Catchment

Located about 65 kilometres west of Sydney in a narrow gorge on the , Warragamba Dam is one of the largest domestic water supply dams in the world. Water is collected from the catchments of the Wollondilly and systems, covering an area of 9,050 square kilometres, to form behind Warragamba Dam. Lake Burragorang is the largest urban water supply in , containing about four times the volume of Sydney Harbour. It is the main water supply for nearly four million people in the Sydney region. Sydney’s evolving water supply system

Australia is one of the driest inhabited Convict labour then developed Busby’s Bore, continents on earth. Water has been vital to the a four kilometre tunnel leading from the survival and prosperity of Sydney since the first Lachlan Swamps, (now Centennial Park) and days of the new colony. The need to ensure a ending in the south–east corner of Hyde Park. reliable water supply through times of By 1852, drought and increasing population led and erratic seasonal rainfall has driven the to the call for a more permanent water supply development of several complex and innovative for Sydney. A third water source, the Botany water supply schemes. Swamps Scheme, began operations in late > TUNNEL INTERIOR, Sydney’s first water supply came from the UNDER OXFORD STREET 1859 but within 20 years this once copious , named for the ‘tanks’ or > VICTORIA BARRACKS: supply of fresh water was depleted. cut into its sides to save water. SHAFT DOWN TO The was Sydney’s The stream, which wound its way through the BUSBY’S BORE fourth source of water supply. Completed in colony before emptying into Sydney Harbour at 1888, the Scheme diverted water from a series , degenerated into an open sewer of weirs on the Cataract, Cordeaux, Avon and and was abandoned in 1826. Nepean rivers to Prospect via 64 kilometres of tunnels, canals and aqueducts, known collectively as the Upper Canal. The building of Cataract, Cordeaux, Avon and Nepean dams between 1907 and 1935 greatly improved the Scheme’s capacity.

< BUSBY’S BORE OUTLET, HYDE PARK. PAINTING BY J.SKINNER Why Warragamba Dam was built

Warragamba River was a short stretch of water, only about 23 kilometres long, that ran from the junction of the Coxs and Wollondilly rivers to its junction with the . The Warragamba River offered two important advantages as a site for a major dam. Firstly it had a large catchment area and secondly the river flowed through a long narrow gorge. A comparatively tall and narrow dam capable of impounding a vast amount of water could be built. Its potential was identified as early as 1845. The first sketch plans were drawn up in 1867, but plans were deferred during the construction of the Upper Nepean dams between 1907 and 1935. An increasing demand > WOLLONDILLY RIVER IN BURRAGORANG In the interim, the Warragamba Emergency for water from an expanding population, and VALLEY BEFORE FLOODING Scheme was built to urgently address Sydney’s a record drought from 1934 to 1942, forced the critical water shortage. This scheme consisted development of Warragamba Dam to ensure of a weir and pumping station on the a reliable water supply. Warragamba River and a pipeline to . It began operating in 1940 and was in use for almost 19 years until the completion of Warragamba Dam. How Warragamba Dam was built

Warragamba Dam was a major engineering > LEFT TO RIGHT feat of the mid 20th Century. CELEBRATING THE TWO MILLIONTH TONNE Following extensive geological examination, two OF CONCRETE POURED temporary dams and a tunnel to divert the river WARRAGAMBA WALL were built first. More than 2,300,000 tonnes of UNDER CONSTRUCTION sandstone were removed from the site. INTERLOCKING CONCRETE BLOCKS Concrete was mixed on site using 305,000 tonnes of cement and 2,500,000 tonnes of sand and gravel. The sand and gravel were Ice was mixed with the concrete to control Pedestrian access between the Warragamba transported from McCann’s Island in the heat generation and to prevent cracks from township and the work area was provided by Nepean River via a unique aerial ropeway. forming. One of the first pre–stressed concrete two suspension bridges, one across Folly Creek towers in Australia was built to house the and the other across the Warragamba Gorge The dam was built in a series of large ice–making plant. just downstream of the dam. interlocking concrete blocks. A system of overhead cableways lifting 18 tonne buckets Residents living in the Burragorang Valley, When the then Premier of NSW, the Hon. was used to place the concrete. which was to be covered by rising waters, were Robert J. Heffron MP, officially opened relocated. More than 64 square kilometres of Warragamba Dam on 14 October 1960, trees were cleared so that they would not rot thousands of guests, workers and their and float downstream, to block the dam’s families gathered for a day of celebration. outlets and crest gates. LIFE IN THE WARRAGAMBA TOWNSHIP Warragamba was established specifically as a construction town. At its peak the town housed about 3,500 people, in mostly prefabricated cottages, as well as barracks for single men and women. Some 1800 men from at least 25 nationalities, many of whom were post WWII immigrants, worked < WARRAGAMBA alongside each other with little friction. PRE–SCHOOL, 1955 Work, family and social activities all centered CONSTRUCTION HISTORY around building the dam. The Water Board provided roads, utilities and other services but Geological Investigations 1942 many of the town amenities could not have River diversion works 1946 existed without the voluntary labour and Site works 1948 fundraising activities of the residents. Excavation 1950 Concrete pour 1953 Unlike other communities that disappeared Completed and opened 1960 almost overnight once dam construction Wall raised five metres 1989 ended, Warragamba has remained a Auxiliary started 1999 close–knit township which even today Auxiliary spillway completed 2002 > proudly highlights its relationship with its > FESTIVAL OF CAROLS, 1964. awe–inspiring neighbour How the dam works

Warragamba Dam supplies bulk water to three HOW THE DAM IS MONITORED water filtration plants where it is filtered and SCA officers inspect and monitor Warragamba distributed to people living in Sydney and the Dam through a network of more than five lower Blue Mountains. kilometres of galleries. They monitor water The best quality water is selected and drawn pressure, seepage, and any physical changes in through screens at three outlets in the the dam structure and its foundations to upstream face of the dam. After flowing by ensure these are within acceptable limits. gravity to the valve house, two pipelines feed Warragamba Dam was designed to deflect the raw water to Prospect water filtration plant slightly as the lake level rises and falls. and via off–takes to smaller filtration plants These deflections are measured regularly at Warragamba and Orchard Hills.The filtered using precise surveying techniques. Sensitive water is then distributed to households, seismic equipment located in the dam and businesses and other users. surrounding catchment monitors earth The five crest gates, central spillway, dissipator movements. Crest gates, valves, pipelines and training walls and apron (stilling pond) all associated equipment are regularly inspected

> THE VALVE HOUSE, WARRAGAMBA manage the discharge of normal floodwaters and maintained. and are critical to dam safety. The auxiliary side spillway will operate only in rare and extreme floods, and will divert excess floodwaters around the dam. owns and operates the 50–megawatt hydro–electric power station at Warragamba which generates green power only when there is a high level of water in the lake.

> PROSPECT WATER FILTRATION PLANT SAFEGUARDING THE DAM Rainfall and flood event studies showed that the dam could experience floods much larger than originally estimated. As the first step in a two–stage solution, the height of the dam wall was increased by five metres. Work took place between 1987 and 1989 as the dam wall was raised and strengthened using post–tensioned steel cables, tying the upper portion of the wall to its base. In early 1999 work began on stage two of the dam safety program, involving the construction of an auxiliary spillway located on the east bank of the dam. During rare and extreme floods, the auxiliary spillway will allow floodwaters to pass safely around the dam, reducing the pressure on the dam wall and ensuring its safety. The auxiliary spillway was completed in 2002.

> 1964 FLOOD Prospect Reservoir

Prospect Reservoir is located on Prospect Creek, approximately 35 kilometres west of Sydney. The dam was completed in 1888 and was the first earthfill embankment dam in Australia. Its original purpose was to store water fed by gravity from the dams of the Upper Nepean system, via the Upper Canal. From there the Lower Canal led to a basin at Guildford, from where water was piped to > AERIAL VIEW OF several reservoirs around the city. PROSPECT RESERVOIR Water from the Warragamba Emergency Prospect Dam was strengthened by the However, Prospect Reservoir remains an Scheme reached Prospect Reservoir in placement of stabilising beams on the integral part of Sydney’s drinking water supply May 1940. The water was piped across downstream face in 1979, and the upstream and is required in times of high demand for Megarrity’s Creek Bridge at Warragamba, face in 1997. water. The filtration plant at Prospect can and another 26 kilometres to Prospect draw water directly from Prospect Reservoir With the commissioning of the Prospect water Reservoir. With the completion of Warragamba if required, providing greater flexibility in filtration plant in 1996, raw water transferred Dam in 1960, Prospect Reservoir continued to sourcing the best quality water. from Warragamba and the Upper Nepean dams play an important role in storing Sydney’s water was sent directly to the treatment facility, supply. A second pipeline linking Warragamba by–passing Prospect Reservoir. and Prospect Reservoir was completed in 1966, significantly increasing the volume of water that could be transferred during peak demand periods. Ensuring dam safety

It is essential that all SCA 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, the SCA has adopted a structured program of surveillance and monitoring that complies with the requirements of the DSC and national and international best practice.

> DID YOU KNOW?

WARRAGAMBA EMERGENCY SCHEME, Megarrity’s Bridge, and Prospect Reservoir and Value House are listed on the State Heritage Register. Monitoring water quality

The SCA conducts extensive routine MAINTAINING GOOD WATER QUALITY water quality and quantity monitoring in the IN THE CATCHMENT catchments, storages and in–flows to The SCA works with government, industry and water filtration plants. Monitoring provides the community to promote good water quality information to enable the best quality water and healthy, sustainable catchments. to be drawn–off into the supply system, and to identify areas requiring special catchment Extensive research is carried out by the SCA to management attention. The SCA also conducts help understand the catchment environment. ENVIRONMENTAL FLOWS regular testing at several locations for the The SCA also plays an important role in presence of the protozoan parasites Giardia ensuring that proposed land use and The SCA recognises that Warragamba Dam can and Cryptosporidium in the water. Information development is compatible with preserving affect the natural flow of water downstream. collected from the SCA’s monitoring water quality. Providing water to the river through programs is used for public health reporting environmental flows is one way the SCA and assessment. Field staff undertake a range of on–ground can help restore ecological processes and activities in the catchments, such as pest biodiversity of water dependent ecosystems. control, fire control, erosion control and repair, regulating access, containing spills, chemical Currently, the SCA releases 43.3 million collections and weed control. In the Special litres of water per day from Warragamba Dam Areas (land closest to the storages) these into the Nepean River for environmental and activities are jointly managed by the National riparian purposes. Parks and Wildlife Service and the SCA. Many successful projects are also undertaken jointly with landholders and community groups including riverbank stabilisation, willow removal, revegetation and riverbank fencing. Fact File > PIPELINES Diameter 2,100/3,000 mm Length 27 km each Capacity 2,600 ML per day

> CONSTRUCTION OF WARRAGAMBA–PROSPECT PIPELINE, FEB 1966 > > >

WARRAGAMBA DAM LAKE BURRAGORANG PROSPECT DAM Height 142 m Total Capacity 2,031,000 ML Height 26m Length 351 m Area 75 km2 Length 2,225m Thickness at base 104 m Length of lake 52 km Total capacity 50,000ML Width of central spillway 94.5 m Length of foreshores 354 km Catchment 9.7km2 Concrete mass 3,000,000 t Maximum depth Width of auxiliary of reservoir 105 m spillway (at mouth) 190 m Catchment Area 9,051 km2 Length of auxiliary spillway 700 m Average annual rainfall 840 mm > > WARRAGAMBA DAM WALL > LAKE BURRAGORANG, WHICH IS PROSPECT RESERVOIR FORMED BY WARRAGAMBA DAM Recreation at Warragamba Dam

Warragamba Dam is located about 65 WARRAGAMBA DAM TEMPORARY LIMITATIONS TO VISITOR kilometres west of Sydney and is an > FACILITIES FACILITIES AT WARRAGAMBA DAM ideal spot for picnicking, barbecues Activities at Warragamba Dam are temporarily and sightseeing. INFORMATION CENTRE i limited due to upgrades to the dam and Facilities are set in natural bushland redevelopment of the recreational facilities. surroundings and include picnic shelters, ELECTRIC BBQS The Visitor Centre and limited picnic facilities shade trees, visitor information centre, will remain open to visitors during this barbecues, viewing area and a children’s period. playground. WATER There is no public access to Warragamba Dam Visiting hours are 10am to 5pm daily (7pm on wall itself and guided tours of the dam are not weekends and public holidays during Daylight PLAYGROUND available. However, there is a viewing platform Saving Time). located at the end of Eighteenth Street, For more information telephone the TOILETS Warragamba with spectacular views of the dam Warragamba Dam Visitor Information Centre and the new auxiliary spillway. on (02) 4720 0349 (10am to 4pm daily, except DRINKING WATER Christmas Day and Good Friday).

For educational excursions and project VIEWING AREA material, please contact our Education Office on (02) 4720 0344/3 PICNIC SHELTERS There are no entry fees to any of our dams. Picnic areas cannot be reserved. Burragorang Lookout & Prospect Reservoir

BURRAGORANG LOOKOUT PROPSECT RESERVOIR PICNIC AREA BURRAGORANG LOOKOUT > FACILITIES Spectacular, panoramic views of Lake Prospect Reservoir Picnic Area, which is Burragorang can also be seen from owned and managed by Sydney Water, is open BBQS Burragorang Lookout, which is located to the public every day of the year between near Nattai in Sydney’s south–west. 10.00am and 4.45pm. Burragorang Lookout is part of the National TOILETS For weekends and public holidays during Parks and Wildlife Service’s (NPWS) Nattai Daylight Saving Time only, the picnic area Reserves System. remains open until 6.45pm. VIEWING AREA Facilities include barbeques, toilets, and children’s playgrounds. PROSPECT RESERVOIR > PICNIC AREA FACILITIES

BBQS

PLAYGROUND

TOILETS

VIEWING AREA How to get there

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> Warragamba Dam is located on the > Warragamba River about 65km west from Sydney. Take Mulgoa Road from Penrith (or Northern and Park Roads from the south) to Wallacia, then Silverdale Road and Farnsworth Avenue to Warragamba. >

Burragorang Lookout is located near > Nattai in Sydney’s south–west.

From Camden, take Druitt Lane, (which turns into Burragorang Road), to Nattai and continue to the lookout. From Picton, take Barkers Lodge Road to Oakdale, then west to Nattai.

> Prospect Reservoir

Travelling west on the M4, take the exit. Turn left at the roundabout, and right at the T–intersection. The entrance to Prospect Reservoir is the second turn on the left. If travelling east on the M4, take the Reservoir Road exit. Turn right onto Reservoir Road. The entrance is approximately two kilometres on the right. Why Special Areas are protected

About 28 per cent of the Warragamba The Special Areas protect our water supply Public access to parts of the Special Areas is catchment is classified as Special Area. because they act as a buffer zone, helping restricted to protect water quality. This benefits In total, Special Areas cover about 3,700 to stop nutrients and other substances the community by: square kilometres of land surrounding SCA that could affect the quality of water entering • ensuring we have safe, clean water water storages. the storages. • protecting large areas of bushland The Sydney Catchment Authority and and plant and animal habitats the National Parks and Wildlife Service • protecting threatened plants (NPWS) jointly manage the Special Areas, and animal species in accordance with the Special Areas Strategic • preserving evidence of Aboriginal heritage Plan of Management. dating back many thousands of years, and • preserving evidence of European exploration, This long–term plan aims to provide high early settlement, and phases of development quality water in the storages, ensure ecosystem such as forestry, mining and dam building. integrity, and improve the environmental quality of the catchment areas. Restrictions and controls are placed on land use, development and access within Special Areas. Activities such as swimming, fishing, boating and camping are prohibited, unless otherwise specified. Access and the Special Areas

ACCESS AND THE SPECIAL AREAS Schedule One (no entry) Under the Sydney Water Catchment In Warragamba catchment, Schedule One land Management Act 1998, there are two water extends in a radius of three kilometres from the quality protection zones – Schedule One and top of the stored water level in Lake Schedule Two. These zones are collectively Burragorang. All access, either on foot or by called the Special Areas. vehicle, and including motorcycles, bicycles and horses, is prohibited. The only exception is an access corridor for walkers from Katoomba to or via Beloon Pass. Schedule Two (restricted access) Schedule Two is the second–tier water quality protection zone, and adjoins Schedule One. Vehicular access is restricted (as are motorcyclists, bicyclists and horse riders), but walkers are generally permitted. Fines of up to $11,000 apply for unauthorised or illegal access in the Special Areas. How you can help keep our catchments healthy

SAVING WATER WATER SAVING TIPS IN THE CATCHMENTS Water is a precious resource. Each of us has a For great water saving ideas, visit the People living and working in the catchment responsibility to reduce the amount of water we Sydney Catchment Authority website areas play a special role in keeping our use – no matter where we live. www.sca.nsw.gov.au. Follow the links to sites catchments healthy. Some of the ways people such as www.sydneywater.com.au for more in the catchments help include: By reducing the amount of water we all use, we information. • using chemicals efficiently and carefully reduce the need to build expensive new water supply infrastructure such as dams, reservoirs • controlling weeds and pests and pipelines. • retaining and planting vegetation to prevent soil loss Reducing the amount of water we all use can • protecting stream bank vegetation to also help make more water available for provide a buffer against pollution environmental flows, which protect the health • managing on–site sewage systems effectively of the rivers downstream of the dams. • encouraging and developing improved sewage The need to manage demand for water is and stormwater management systems reflected in the Operating Licences of both the • preventing bushfires SCA and Sydney Water. The SCA is working with • reporting spills, and Sydney Water to encourage water saving • getting involved in a Landcare, Streamwatch actions around the home, garden and office. or other local community group. The SCA 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 the SCA is reducing the

> USING LESS WATER HELPS KEEP amount of water we use. OUR CATCHMENTS HEALTHY