Cataract Dam - Appin, NSW, Australia
S 34° 15.921 E 150° 48.266
56H E 297858 N 6206240
This marker is at the eastern end of the Cataract Dam wall, near the car park.
Waymark Code: WM11A9M
Location: New South Wales, Australia
Date Posted: 09/15/2019
Views: 1
The circular National Engineering Landmark marker is inset to a faced sandstone block at the start of the parapet on the southern side of the dam wall. Beside it is the rectangular Institution of Engineers Australia plaque, which reads:
[Crest] CATARACT DAM
Contractor Lane and Peters completed this basalt
concrete faced sandstone-block masonry dam in
1907 for the NSW Public Works Department to a
design by Principal Engineers L.A.B. Wade and T.W.
Keele. It was the first large city water storage dam
in Australia, the fourth largest of its type in the
world and the first of the four Upper Nepean Dams
which provided water reserves for Sydney against
the effects of drought.
Dedicated by
The Institution of Engineers, Australia
and Sydney Water 1995
From the PDF in the link below:
"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-link p19]
Visited: 1347, Wednesday, 10 July, 2019