|State||New South Wales|
|Regions||Sydney Basin (IBRA), Southern Highlands, Macarthur|
|Part of||Hawkesbury-Nepean catchment|
|- left||Avon River (Wollongong)|
|- location||below Mount Keira|
|- elevation||315 m (1,033 ft)|
|Mouth||confluence with the Nepean River|
|- location||near Wilton|
|- elevation||147 m (482 ft)|
|Length||32 km (20 mi)|
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.
- List of rivers of Australia
- List of rivers in New South Wales (A-K)
- Rivers of New South Wales
- Upper Nepean Scheme
- "Cordeaux River". Geographical Names Register (GNR) of NSW. Geographical Names Board of New South Wales. Retrieved 19 December 2008.
- "Map of Cordeaux River, NSW". Bonzle Digital Atlas of Australia. Retrieved 27 February 2013.
- "Upper Nepean dams – Cataract, Cordeaux, Avon, Nepean". Visiting dams. Sydney Catchment Authority. Retrieved 27 February 2013.