Cordeaux Dam

Cordeaux Dam

Yesterday,  we joined our friends from the Avid Travel Club for a trip to the heritage listed Cordeaux Dam.  It is one of four dams in the catchment of the Upper Nepean Scheme.  It is situated 94 kilometres south of Sydney.  On the way down to Wollongong it is off the Picton Road.  It was created by damming the Cordeaux River.  Cordeaux Dam is a very well built and handsome  structure, with a strong Egyptian styled architectural character which suits the monumental nature of the structure.  It was built of sandstone blocks, quarried at the site and has the longest dam wall of all four dams.  Massive Egyptian style stone gateways guard the entrance to the dam wall, complete with Lotus Columns and the leafy picnic grounds feature stands of tall palm trees and other reminders of past times.

Here is the Entrance Gateway to the Walkway across the Dam wall.  The Dam is 57 metres high.   You will notice the neo-classical and Art Deco influences in the design of the Gateway and the structures along the Walkway.  

 Here is a detail of the top of the Lotus columns inside the main Entrance Gateway.  The great columns suggest an origin in pre-classical times, their bulges and fluting harking back more to Ancient Egypt or Babylon than Greece.

I love the view from this little window, which is inside a room at the far end of the Dam wall.  The Reservoir holds 93 megalitres of water supplied from a 91sqm catchment which forms a vast lake of water. 

A very pretty view along the shoreline of the Lake.  The Dam is set within the valley of the Cordeaux River.  Upstream of the Dam wall this setting is characterised by the broad expanse of the Lake bordered by the crests of the valley sides. 

Looking towards the end of the Dam wall.

The concrete battlements over the top of the Dam hide a footing of vast stone blocks carved from the surrounding area and which make up the bulk of the dam itself.

Technical Details.  (taken from www.stonequarry.com.au)

"Cordeaux Dam. Completed 1926. Masonry dam (sandstone), with 218,440 cubic yards of concrete. 1,327 feet wide; 996 feet above sea level when full; 156 feet deep. Lake is 1931 acres in size. Catchment area 35 miles square. Average annual rainfall 56". Try converting this to metric!

Part of the water catchment area for the city of Sydney.

But how does it get to Sydney?

While you are gazing at the dam you are only seeing part of this engineering marvel.

At Pheasants Nest (near where the roadhouse is on the freeway) water is diverted to the Nepean Tunnel (7.5kms long) to the Cataract River at Broughton Pass Weir. (Between Appin and Wilton.)

From there it flows through Cataract Tunnel, to the Upper Canal where it flows some 57 kilometres to the Prospect Water Filtration Plant near Prospect Reservoir, and from here it is reticulated throughout the city."

After a walk along the length of the Dam Wall, we drove to the picnic grounds and enjoyed a wonderful picnic lunch, (courtesy of Avid Travel)  set out by Nathan and the team, in one of the picnic shelters.  It was a great outing on a perfect Summer's day.