The Cordeaux River is a tributary of the Nepean River, and hence of the Hawkesbury River, in New South Wales, Australia.[1]
The headwaters of the river are located on the west slopes of the coastal escarpment some 10 kilometres (6.2 mi) west of Wollongong and the Pacific Ocean. The upper reaches of the river are impounded by the Cordeaux Dam. Below the dam, the river flows in a north-westerly direction before being joined by the Avon River at a point just to the south of Wilton. About 1 kilometre (0.62 mi) downstream of this confluence, the Cordeaux itself flows into the Nepean River. In total, the river is some 37 kilometres (23 mi) long.[1]
The river is an important source of water for the Sydney region. Water is collected by the dams, weirs and aqueducts of the Upper Nepean Scheme.