Cataract Dam [NSW, Australia]
S 34° 15.920 E 150° 48.240
56H E 297818 N 6206242
This dam at Appin was built in 1907, to help supply water for southern Sydney.
Waymark Code: WM11A9K
Location: New South Wales, Australia
Date Posted: 09/15/2019
Views: 0
The gravity dam south of Sydney stands 56m tall, is 247m long, and holds 94.3 gigalitres. It was the first of four dams built in the Upper Nepean Scheme. A 61cm gauge tramway of 8.8km was built to the quarry for the basalt required to make to the pre-cast moulded concrete blocks of the upstream face of the dam. [ex-Wikipedia]
"The dam was built by the Public Works Department and the construction contract was let to Messrs Lane and Peters. E.M. de Burgh, then the Principal Assistant Engineer for Rivers, Water Supply and Drainage, was given special responsibility for the construction.
"By June, 1903, much of the area to be submerged had been cleared of timber and by the end of the year the foundation excavations were in progress. The dam was built of cyclopean masonry composed of sandstone blocks weighing from two to four and a half tons. These were quarried at the site and bedded in a 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 consisted of basalt concrete, six feet (1.8m) thick in the lower section and three feet (0.9m) thick in the upper levels. There were two lines of 48 inch (122cm) diameter pipes which passed through the dam and discharged water into the 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 about the middle of the dam wall 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 wither side."
"The total cost of construction of the dam was £329,136 ($658,272) when the dam was handed over to the Metropolitan Water Sewerage and Drainage Board. The reservoir was filled to capacity for the first time on the 13th January, 1911. However, it was realised that the spillway should be widened to avoid the risk of floodwaters overtopping the wall. This work was completed in 1915.[ex- (
visit link) p19]
Visited: 1347, Wednesday, 10 July, 2019