Woronora-Penshurst Pipeline

  • Number
    4570509
  • Primary address

    282, Woronora Dam to Penshurst Reservoir Woronora, Sutherland, Penshurst, . NSW
    LGA: Sutherland
    LGA region: Sydney
    DUAP region: Sydney South

  • Owner
    Sydney Water
  • Current use
    Water Supply Pipeline
  • Former use
    Water Supply Pipeline
  • Item type
    Built
  • Item group
    Utilities - Water
  • Item category
    Water Pipe
  • Parcels

    Parcel code:
    Lot number:
    Section number:
    Plan code:
    Plan number:
    Updated: 12 February 2002

  • Curtilage/Boundary
    The physical boundary and curtilage of the Woronora-Penshurst Pipeline extends to the boundary of Sydney Water land along the route of the pipeline. The curtilage includes the original pipeline and all infrastructure associated with the pipeline such as bridges, tunnels, valve houses, flow metres, cross-connections and pumping stations.
  • Statement of significance
    The Woronora - Penshurst Pipeline is significant because of its relationship with the Woronora Dam, the fifth of the water supply dams built as part of Sydney's water supply. Woronora Dam was completed in 1942 and is the only one of Sydney's water supply dams which is not part of the Upper Nepean/Warragamba/Shoalhaven interconnected system. The dam and pipeline were built with the objective of supplementing Sydney's water supply whilst the much larger Warragamba Dam was being constructed. The Woronora - Penshurst Pipeline is culturally significant as it supplies water from Woronora Dam to the areas of Sutherland, Cronulla, Engadine, Heathcote, Helensburgh, Stanwell Park and the areas just north of Georges River. The pipeline is 27.1 km long and consists of 42 inch (1.07m) mild steel spirally welded pipes. The pipeline has technical significance because of its corkscrew construction method. At the time of construction only small width steel sheets were available and in order to obtain a large diameter pipeline these were welded together in a spiral technique. The pipeline crosses the Como Railway Bridge which was converted to a cycleway bridge by Sydney Water. The bridge is of State significance and listed by the National Trust of Australia (NSW) and is on the Register of the National Estate. The bridge was constructed by John Whitton and a significant technical accomplishment. It was placed into service in 1885 and is the tenth in a series of twelve related bridges. It was the first of the series with six spans (earlier bridges having 1 to 4 spans). When completed it was the fourth longest metal truss bridge in Australia. It carried single track railway lines which were the first in Sydney to be electrified in 1926. The operational and physical curtilage of the pipeline extends to the original pipelines and all the supporting/associated structures. The visual curtilage extends further as the pipeline is a major feature of the landscape between Woronora Dam and Penshurst.
  • Endorsed significance
    Local
  • Designer
    MWS&D Board / PWD
  • Builder
    Water Board
  • Year started
    1936
  • Year completed
    1942
  • Circa
    No
  • Physical description
    Woronora Dam is the only one of Sydney's major water supply storage dams which is not primarily part of the Upper Nepean/Warragamba/Shoalhaven interconnected system. It has the smallest catchment area, 85 sq km, of any of the water supply dams. The dam is located on the Woronora River, just downstream of its confluence with the Waratah Rivulet, about 6 km northwest of the township of Waterfall. Water is discharged from the lake via two 3 feet (0.9m) diameter pipes in the base of the dam, these lead to a valvehouse located at the bottom of the downstream face of the wall. The water then flows along a 16.1 mile (27 km) pipeline, consisting of 42 inch (1.07m) mild steel spirally welded pipes lined internally with 1 3/8 inch (34mm) cement mortar. The pipeline crosses the Georges River on the old railway bridge at Como and discharges into the two elevated Penshurst Reservoirs. The 27 km length of pipeline main was constructed in four sections. The first section commences at the outlet of the Woronora Dam and then follows the left bank of the Woronora River. It crosses the river on a concrete causeway and continues along the right bank to No.1 tunnel, approximately 400 m in length, some 3.2 km from the dam. The line then follows Heathcote Creek to near its junction with the Woronora River. The second section follows the right bank of the Woronora River as far as No.2 tunnel, 13.5 km from the dam, where it continues on to cross Forbes Creek. The tunnel is approximately 244 m long and had to be lined with concrete because of the poor strata encountered. The main crosses Forbes Creek on a specially designed structure. A pressure valve is located at Forbes Creek to reduce the pressure on the main downstream. The section ends at Grand Parade, Sutherland, where 20 inch (508mm) and 18 inch (457mm) branches feed the Sutherland Reservoir. In the third section from Grand Parade to Como the main is laid partly above ground and partly in trench and crosses under the railway line near Jannali in a concrete culvert. At the southern end of the railway bridge over the Georges River, the 48 inch (1.22m) main bifurcates into two 24 inch (0.61m) mains which are carried across the river on brackets welded to the lower chord on each side of the bridge. After passing over the Georges River the fourth section of the main reverts to 48 inch (1.22m) diameter and follows the eastern side of the railway line to Oatley. At this point it deviates and proceeds principally underground along streets to the intersection of Hillcrest Avenue and Laycock Road, Penshurst, whereby a 36 inch (0.91 m) branch runs to the Penshurst Reservoirs.
  • Modifications made
    Originally camouflaged during WW2 against potential threat or sabotage. After this period it was painted silver and then in 1980 the pipelines were repainted green to blend in with native bushland.
  • History
    The Woronora Dam was the fifth of the water supply dams built as part of the development of Sydney's water supply, and represented the first occasion where the water supply was to be provided from somewhere other than the four dams of the Upper Nepean Scheme (ie Cataract, Cordeaux, Avon and Nepean Dams). Construction of the Woronora Dam commenced in 1927, with the two objectives of providing a water supply for the Sutherland/Cronulla area, and supplementing the Upper Nepean Scheme whilst the Warragamba Dam was being built. The dam and pipelines were designed by the Metropolitan Water Sewerage and Drainage Board in conjunction with the PWD and it was the first dam built entirely by the Board, after the transfer of the construction division from the PWD. The primary function of the Woronora Pipeline when first constructed was to convey water from Woronora Dam to Penshurst Reservoir. Consequently areas previously served by pumping could be supplied with gravitational water. Since its construction however, expansion in the Sutherland Shire has lead to the pipeline being used to supply Sutherland and Cronulla, Engadine, Heathcote, Helensburgh, Stanwell Park, and the areas just north of Georges River. The scheme adopted by the Board in 1925, for the development of the Woronora Catchment, was concerned with the supply of only the Cronulla and Sutherland areas, and provided for the construction of a low dam with a 15 inch (380mm) trunk main and pumping station. When the Board decided in 1929 to fully exploit the catchment for Metropolitan Supply, the amended scheme provided for a much higher dam and a larger diameter pipeline to Penshurst. Supply was given to Sutherland and Cronulla by the erection of a pumping station on the pipeline (opposite Heathcote), a reservoir near Heathcote Railway Station and other incidental works. Financial difficulties that arose early in 1930 resulted in the suspension of operations, which were not resumed until 1936. The amended program provided for a 48 inch (1.22 m) diameter pipeline. Further delays were experienced and it was not until 1940 that it was possible to accelerate progress with a view to completing work by June 1941. However, the heavy demand for steel arising from the war created extreme difficulty in securing delivery of the necessary pipes and commissioning of the pipeline did not occur until November 1942.
  • National
    Economy
  • State
    Health
  • Local
    Water Supply
  • National
    Economy
  • State
    Environment - cultural landscape
  • Local
    (none)
  • National
    Settlement
  • State
    Utilities
  • Local
    Water Supply
  • Local description
    Relates to the planning, development, expansion and provision of water supply.
  • National
    Settlement
  • State
    Towns, suburbs and villages (Townships)
  • Local
    (none)
  • a) Historical
    The Woronora - Penshurst Pipeline is historically significant because of its relationship with the Woronora Dam, the fifth of the water supply dams built as part of Sydney's water supply. Woronora Dam was completed in 1942 and is the only one of Sydney's water supply dams which is not part of the Upper Nepean/Warragamba/Shoalhaven interconnected system. The dam was built with the objective of supplementing Sydney's water supply whilst the much larger Warragamba Dam was being constructed. The pipelines were constructed with the purpose of transferring water from the dam site on Woronora River, near Waterfall, to the Penshurst Reservoirs, whence the Cronulla/Sutherland area could be supplied with gravitational water.
  • c) Aesthetic
    The pipeline was originally camouflaged during the second world war. It was repainted silver after the war period. Around 1980 environmental measures resulted in the pipes being repainted green to blend in with the natural bushland. The pipeline also passes through an area which is now the Heathcote National Park.
  • d) Social
    The Woronora - Penshurst pipeline is socially significant as it supplies water from Woronora Dam to the areas of Sutherland, Cronulla, Engadine, Heathcote, Helensburgh, Stanwell Park and the areas just north of Georges River and as such is likely to be held in high regard by the broad community for the function it serves. The completion of the Woronora Dam was a significant step in the continuing process of providing reliable water supply to Sydney and surrounding areas. It further served the purpose of providing an interim measure, when it was realised that the growth of Sydney would require a water supply augmentation of a magnitude which could only be met by the construction of a major dam on the Warragamba River. The construction of the pipeline allowed for the career of Sir William Hudson to advance. He was the resident engineer on the Woronora Dam/Pipeline project and went on to be the Engineer-in-Chief of the Water Board and the first Commissioner of the Snowy Mountains Scheme. The Woronora Dam and Pipeline also strengthened Sydney's defences during WW2 by supplying an independent and alternate supply to the Upper Nepean Scheme in case of emergency.
  • e) Research
    The pipeline is 27.1 km long consisting of 42 inch ( 1.07m) mild steel spirally welded pipes. A corkscrew technique was used in order to obtain a large diameter pipeline, as only small width sheet steel was available at the time of construction. A lack of expansion joints has resulted in minor leakages along the length of the pipeline. The pipeline did not have adequate expansion joints when built. This caused some leakage of joints at later stages. The pipeline has numerous river and creek crossings along its route. At Woronora River and Forbes Creek the pipeline crosses the water via single pipe aqueducts. At Georges River the pipeline bifurcates and crosses the water via the former Como Railway Bridge. This bridge is significant as it is a Whitton's Lattice Girder Bridge and was built in 1885. The pipeline bifurcates when it crosses the bridge in order to equalise the load on the structure. The bridge is no longer used by the railway and is now owned by Sydney Water. It is presently used only for pedestrian and bicycle access. The pipeline also passes through a rock tunnel known as Dingo Tunnel.
  • f) Rarity
    One of a number of water supply pipelines in Sydney.
  • g) Representative
    Representative of water supply pipelines and of infrastructure associated with the Woronora Dam which is the only one of Sydney's water supply dams that is not part of the Upper Nepean/Warragamba/Shoalhaven interconnected system.
  • Integrity assessment
    Considerably intact.
  • List name
    Local Environmental Plan
  • Date listing listed
    01 January 2000
  • List name
    Heritage Act - s.170 NSW State agency heritage register
  • Reference number
    002271
  • Date listing listed
    01 January 2000
  • Title
    Sydney Water Heritage Study
  • Author
    Graham Brooks and Associates Pty Ltd
  • Published
    1996
  • Item reference number in study
    002271
  • Map showing the location of the Woronora - Penshurst Pipelines. Source: Sydney Water Board Journal, January 1957.
    Map showing the location of the Woronora - Penshurst Pipelines. Source: Sydney Water Board Journal, January 1957.
    Created by: Sydney Water
    Creation date: 01 January 2057
  • Woronora Dam - River Bottom and North Abutment.
    Woronora Dam - River Bottom and North Abutment.
    Created by: Sydney Water
    Creation date: 09 July 2029
  • Woronora Pipeline - Forbes Creek.
    Woronora Pipeline - Forbes Creek.
    Created by: Sydney Water
    Creation date: 21 January 2043
  • Woronora Pipeline - Brackets and Decking on Como Railway Bridge.
    Woronora Pipeline - Brackets and Decking on Como Railway Bridge.
    Created by: Sydney Water
    Creation date: 18 March 2041
  • Woronora - Penshurst Pipeline - Como Bridge.
    Woronora - Penshurst Pipeline - Como Bridge.
    Created by: Sydney Water
    Creation date: 12 November 2042
  • Woronora Dam - Lower Valve House foundation block and access bridge to the pipeline.
    Woronora Dam - Lower Valve House foundation block and access bridge to the pipeline.
    Created by: Sydney Water
    Creation date: 08 May 2041
  • Data entry status
    Basic
  • Entered
    03 June 1998
  • Updated
    05 March 2014