The Cordeaux Dam is 57 metres high, with a length of 405 metres. The catchment area is 91 square kilometres.

April 7, 2020: In response the ongoing public health emergency and to support social distancing measures, ALL WaterNSW Dams and Recreation areas will be closed to public access until further notice. Please check the WaterNSW website for updates.

Remarkable for its Egyptian inspired architecture, a visit to Cordeaux Dam is like stepping back in time. Massive Egyptian style stone gateways guard the entrance to the dam wall, and the leafy picnic grounds feature stands of tall pine trees and other reminders of past times. Cordeaux is one of four dams that make up the Upper Nepean water supply scheme south of Sydney on the Illawarra Plateau.

Cordeaux was the second of the four dams constructed to collect water from the Illawarra Plateau. Created by damming the Cordeaux River, construction started in 1918 and was completed in 1926.

Together with Cataract Dam, Cordeaux’s main role today is to supply water to Camden, Campbelltown and Wollondilly council areas via the Macarthur water filtration plant.

Together, the Nepean, Avon, Cataract and Cordeaux dams also provide an additional supply of water for Sydney, via Pheasants Nest Weir, Broughtons Pass Weir and the Upper Canal.

Work on Cordeaux Dam started in 1918 and was completed in 1926. The wall was built using cyclopean masonry – sandstone blocks, quarried from the site, fitted into an irregular pattern and packed with sandstone concrete.

Cordeaux is a curved dam with an unlined spillway to the left of the dam wall. Cement and metal were transported to the site from the main southern railway 21 kilometres away using a five kilometre steam operated aerial ropeway built across the Nepean Gorge. The final journey was completed by a narrow gauge rail line.

A township for workers was constructed, with barracks for single men and small cottages for married men.

Top 5 things to see and do

1. Be photographed in Egypt!

Stand under one of the massive stone gateways at either end of the dam wall and have your photo taken. Your friends may think you’ve been on holidays in Egypt! The gates were inspired by the popularity of all things Egyptian following the discovery of King Tutenkhamun’s tomb in 1922. Construction of Cordeaux Dam started in 1918 and was completed in 1926.

2. Walk across the dam wall to the spillway

After your photo under the Egyptian style gateway, walk across the curved wall of the dam. It’s longer and lower than the other Upper Nepean dam walls, 405 metres long but only 57 metres high. Pause halfway and admire the views of the lake upstream. Walk to the end for an impressive view of the spillway, framed through the Egyptian style archway.

3. Step back in time

Be on the lookout for reminders of the dam’s glory days as a picnic spot in the 1930s and 1940s, when Upper Nepean dams competed for the most beautiful gardens. In the upper picnic area, look out for remnants of old garden layouts and a grotto between a large Monterey Pine and a very large Eucalypt. Enjoy the stands of mature pine trees and a crazy-paved stone path leading to a lower picnic area with a series of grassed terraces.

4. Visit the memorial

A memorial garden in the picnic grounds and a plaque on the valve house on the dam wall pay tribute to Guy Chalmers Clift, 37, the Resident Engineer in charge of the dam’s construction. On 10 March 1924, Clift and Constable James Flynn, 27, a local police officer, were shot while taking a suspect to Appin Police Station after a bungled attempt to steal the Cordeaux payroll. The intoxicated prisoner, William Simpson, 34, was later captured at the Royal Hotel in Appin, and was charged with the two murders. He was hanged at Long Bay Gaol in December 1924.

5. Relax with a picnic and soak up the views

Relax with family and friends in the landscaped grounds. Throw down a rug and enjoy a picnic – you’re sitting on the site where the dam builders lived in the 1920s! Look for remnants of an old road, drains and a tennis court. Picnic facilities include electric barbeques, drinking water, toilets and a children’s playground. Drive or walk along an avenue of Monterey Pines to the lower carpark and toilets near the dam wall. The wall and picnic area provide excellent views of the lake in its natural bushland setting.