The Frederick River is a river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 in the Pilbara of Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

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The headwaters of the river rise in the Kenneth Range then flow in a south westerly direction until it merges with the Lyons River

Lyons River

The Lyons River is a river in the Gascoyne of Western Australia.The headwaters of the Lyons rise just west of the Teano Range and flows South West until it merges with the Gascoyne River of which it is a tributary...

 near Cobra Station homestead.

The only tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Frederick river is Mulga wash.

The river was named in 1866 by the explorer Edward Hooley

E. T. Hooley

Edward Timothy Hooley , usually known as E. T. Hooley or Tim Hooley, was an explorer in Western Australia, who in 1866 pioneered an overland stock route from Geraldton to the Ashburton River...

 who was on expedition in the area after Frederick Roe , the son of John Septimus Roe

John Septimus Roe

John Septimus Roe was the first Surveyor-General of Western Australia. He was a renowned explorer, and a Member of Western Australia's Legislative and Executive Councils for nearly 40 years.-Early life:...

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