Cataract Dam
The Cataract Dam is a heritage-listed dam in Cataract, New South Wales, Australia, provides water to the Macarthur and Illawarra regions, the Wollondilly Shire, and metropolitan Sydney. It is one of four dams and weirs in the catchment of the Upper Nepean Scheme. Completed in 1907 under the supervision of Ernest Macartney de Burgh, the dam is currently owned by Water NSW, an agency of the Government of New South Wales. The dam was listed on the NSW State Heritage Register on 18 November 1999.
Structural details
A gravity dam with an unlined side spillway extending from the left abutment, it is tall; long; and it holds of water. Cataract Dam was the first dam built in the Upper Nepean Scheme. It was also the first dam in Australia to use pre-cast moulded concrete blocks for the upstream face of the dam. The downstream face is of mass poured basalt concrete, with a basalt facing. A readily accessible source of suitable rock was located at Sherbrooke, situated near the top of Bulli Pass. To transport the basalt from the quarry to the dam construction site, a gauge steam tramway, long, was constructed.The dam is built of cyclopean masonry, composed of sandstone blocks weighing from. These were quarried at the site and bedded in cement mortar. The vertical joints were filled with basalt or sandstone concrete. The upstream face consisted of basalt concrete moulded blocks set in a cement mortar. The downstream face was of basalt concrete, thick in the lower section and thick in the upper section. There were two lines of diameter pipes which passed through the dam and discharged water into the Nepean River. The flow is controlled by a Larner Johnson needle valve. The dam wall was given a decorative finish. The upstream parapet was castellated with sandstone blocks while the top of the downstream wall was corbelled in concrete. In approximately the midsection of the dam stands the valve house. This is finished in quarried sandstone blocks with ashlar coursing. It features a steeply pitched slate-covered pipped roof topped with finials and gables at either side.
Dam construction began in 1902 and was completed in 1907, and the spillway was widened in 1915. E. M. de Burgh was the supervising engineer for the project from 1904.
History
The Upper Nepean Scheme was commenced in 1880 after it was realised that the Botany Swamps scheme was insufficient to meet Sydney's water supply needs. The Nepean project consisted of the construction of a weir across the Nepean River to divert of the rivers Cataract, Cordeaux, Avon and Nepean, to the Prospect Reservoir.The design and construction of Cataract Dam was undertaken by the Water Supply and Sewerage Branch and Harbour and Rivers Branch of the New South Wales Public Works Department. The construction of the dam necessitated the knowledge and experience of a number of engineers employed in the branches at the time including Cecil Darley, Leslie Wade, Henry Dare and Ernest M. de Burgh. The successful completion of the dam and its continuation of use as a water supply dam are a lasting testament to the professional capabilities of the late Victorian/Edwardian era generation of engineers of the Public Works Department. The association of Thomas Keele with the initial dam proposal, and the subsequent problems associated with the cost and the ongoing Royal Commissions into the project was immortalised through Banjo Paterson's satirical ballad The Dam that Keele Built.
Appin
Appin town's name came about, despite that most local settlers came from Irish stock, due to Governor Macquarie's arrival in the colony in 1810. At the time, Government House was in Parramatta and one of Macquarie's first intentions was to travel into the nearby country to discover the best land from which the colony could be provided with food. It was already known that the most productive area for that purpose was the Hawkesbury River country, but these districts had proven precarious because of severe flooding which caused great losses in crops and stock.The land Macquarie intended to study lay between the Nepean and Georges Rivers. There had been no identification of the land which ran as far south as the Cataract River and was bounded on the west by the Nepean River and on the east by the Georges River. On completion of his survey, this area reminded him so much of his own district in Scotland that he called it the Airds district. Some time later he named the section south, including Mount Gilead, Appin.
One of the earliest buildings in the town, still standing, is the Anglican school, where the first generation of children born in Appin received their education. This was erected about 1815.
Macquarie gave many grants of land in order to develop the land. The first was granted to Sydney magistrate and acting commissary-general, William Broughton. There were several other grants of smaller amounts, made on condition that after five years, unless sufficient progress had been made in cropping and stocking, the land would revert to the Crown. The district became a great supplier of wheat, corn and barley, carried to Sydney by wagons pulled by teams of bullocks or horses.
The northern boundary of the Appin district is the property known as Mount Gilead, which was granted to Reuben Uther. Some years later it was purchased by a Sydney businessman, Thomas Rose, who was credited with building the first dam for water conservation in the colony. This was carried out very thoroughly and with great expense. He was generous with the water conserved and allowed his neighbours to water their stock in very dry times.
He applied to the Governor for some reimbursement, but was refused. This dam was built in 1824. In 1836 Rose built the huge stone windmill, one of the largest of its kind which gave great service for many years grinding wheat of the surrounding areas. In those early years, in a good season, yields in some areas were as high as 45 bushels to the acre. The windmill is still standing; that is the four-storey tower which has long been converted to a water tank; but the top hammer and sails have long-since disappeared.
On the southern side, Mount Gilead was joined by the Hume properties, Beulan and Meadowvale. These and others such as Fairview, Blossom Lodge, Mount Carlon and the big poultry farm conducted by Ingham enterprises are all on the western side of the Appin Road. Opposite the last property is one known as Kildare, one of the pioneer homes of the Irish Dwyer family.
Further west was Lesson's Green, an grant to William Crowe, the northern boundary of which joined a grant to John Dwyer, which in turn joined Macquarie Dale, a second grant of made to William Broughton in 1816, which ran as far as the Nepean River. South of this is the property of Elladale, of granted to Alexander Riley in 1812, the boundary to Macquarie Dale is Elladale Creek. This was later greatly reduced in size by subdivisions and sales. By about 1840, when purchased by Rev. Sparling, the first incumbent at St. Mark's Anglican Church in Appin, it had shrunk to.
On its southern boundary, it was joined by Broughton's Lachlan Vale. That property in turn joined John Kennedy's original grant, that he named Teston. In later years, different owners added to it, growing the property to over. This acreage on the south side joined the area known as Mount Brittain of, a grant to William Sykes. With further grants it became over.
Further south, Mount Brittain joined a grant to James Jordan, the southern boundary being the Cataract River and here was the place known as Jordan's Crossing, where the road from Mount Keira crossed the river. There were a number of small grants on the way back to Appin such as those of John Firth, Edward McGee, John Trotter, Nicholas Bryan and Matthew Pearce and several others. Laurence D'Arcy was also granted joining Jordan's and named it Spring Valley.
Other grantees were James Byrne and Andrew Byrne who had a grant between what is now Ingham enterprises and John Anderson's property that he named Ousedale, the creek that ran through it still bearing this name. A number of the small grants were brought together by purchase and the well-known property of Windmill Hill came into being, owned by William Larkin. This name was given to it because Larkin built a timber windmill on the highest part of it and it gave great service for many years. The farm later became the property of the Winton family who ran it as a dairy farm until recent years.
Appin has two solidly-built stone churches, St. Bede's Roman Catholic and St. Mark's Anglican. Both were built about the same time, 1840–41 and have stood the test of time. Both are equipped with very good bells.
The population of Appin was quite large: in 1825 the number was 562. A large number of farmers were engaged in wheat, barley, corn and vegetable growing for the Sydney market.
Upper Nepean Scheme
The Upper Nepean Scheme was commenced in 1880 after it was realised that the Botany scheme was insufficient to meet Sydney's water supply needs. The scheme was estimated to be capable of supplying the needs of a population up to 540,000. In 1902, a severe drought caused the water in Prospect Reservoir to fall below gravitational flow to the Lower Canal, resulting in a serious water shortage for Sydney's 523,000 inhabitants.The seriousness of the position led the NSW Government, in March 1902, to appoint a Royal Commission to inquire into and report upon the Sydney water supply system. The main recommendation of the Commission was that a storage dam be constructed at a point below the junction of Cataract Creek with the Cataract River. The site was selected as a result of a joint investigation and survey by the staff of the Public Works Department and the Water Board. The survey reports proposed the construction of a dam capable of impounding approximately 7000 million gallons of water, with the option of raising the walls at some future time to allow for the catchment of up to.
The Act authorising the construction of the dam was passed in 1902 and provided for a wall of with a storage capacity of. By June 1903, much of the area to be submerged had been cleared of timber, with excavations for the foundations having begun by the end of the year.
The contract for the work was let to Messrs Lane and Peters and, by 1905, was well underway with a completion date expected within two years. The contract was for a dam high from the natural flow of the river, which would store up to. During construction, the Minister for Public Works, in a measure of economy, directed that the dam wall be reduced in height by thereby reducing the storage capacity from. The Board however, acting on advice of its President, urged the Minister to have the dam built to its original dimensions. This request was then forwarded to a Royal Commission which, after a full investigation, recommended that the dam be built to its full height and capacity. The work proceeded on this basis and was completed toward the end of 1907 for a total cost of $658,272 and was transferred to the Board on 10 June 1908. The reservoir was filled to capacity for the first time on 13 January 1911, at which time it became obvious that the spillway should be widened to avoid any risk of flood waters overtopping the wall. This work was completed in 1915.
In December 2016 the state government gave approval for the controversial South 32 Dendrobium coal mine, in the Metropolitan Special Area, created to protect the waters of Cataract, Cordeaux, Avon and Nepean Reservoirs.