|State||New South Wales|
|Region||Sydney Basin (IBRA), Southern Highlands, Macarthur|
|⁃ location||below Mount Keira|
|⁃ elevation||315 m (1,033 ft)|
|Mouth||confluence with the Nepean River|
|147 m (482 ft)|
|Length||32 km (20 mi)|
|River system||Hawkesbury-Nepean catchment|
|⁃ left||Avon River (Wollongong)|
The Cordeaux River rises on the western slopes of the Illawarra escarpment, below Mount Keira within the Wollongong local government area and flows generally north and northwest, joined by the Avon River, before reaching its confluence with the Nepean River, south of Wilton. The river descends 168 metres (551 ft) over its 37-kilometre (23 mi) course.
The river is impounded by Lake Cordeaux, one of four reservoirs within the Upper Nepean Scheme that supplies potable water for greater metropolitan Sydney. Located near Ryans Crossing, approximately 94 kilometres (58 mi) south-west of Sydney, construction of the dam wall on the Cordeaux River commenced in 1918 and was completed in 1926.
The "address locality" of Cordeaux is defined as a suburb of the City of Wollongong, "lying beside the Cordeaux River between Lake Cordeaux and Upper Cordeaux No 1 Dam". At the 2016 census, it had no population.
- "Map of Cordeaux River, NSW". Bonzle Digital Atlas of Australia. Retrieved 27 February 2013.
- "Cordeaux River". Geographical Names Register (GNR) of NSW. Geographical Names Board of New South Wales. Retrieved 19 December 2008.
- "Upper Nepean dams – Cataract, Cordeaux, Avon, Nepean". Visiting dams. Sydney Catchment Authority. Archived from the original on 5 April 2013. Retrieved 27 February 2013.
- "Cordeaux". Geographical Names Board of New South Wales. New South Wales Government. Retrieved 23 July 2017.
- Australian Bureau of Statistics (27 June 2017). "Cordeaux". 2016 Census QuickStats. Retrieved 23 July 2017.