[3][1][5] The Murchison River basin covers an area of about 82,000 square kilometres (31,660 sq mi) in the Mid West region of Western Australia.

It extends about 550 km (340 mi) inland from the Indian Ocean, onto the Yilgarn Craton east of Meekatharra and north of Sandstone.

The drainage lines from these lakes merge to form the Murchison River about 90 km (56 mi) north-northeast of Meekatharra.

The Murchison River rises on the southern slopes of the Robinson Ranges, about 75 km (47 mi) north of Meekatharra in central Western Australia.

It eventually turns to the southwest, passing through one more dogleg before discharging into the Indian Ocean at Kalbarri, the only town on the river.

The maximum age for initiating major down-cutting of the Murchison Gorge, in response to regional Quaternary tectonism, is Late Eocene (33.9–38 million years ago).

Although this channel is permanently open, it is usually very narrow and shallow, and so is now dredged every year to allow passage by western rock lobster fishing boats.

[15] The southern branch flooded out to a distance of 6 miles (10 km) from the river bank in 1884 and the main homestead at Moorarie Station was washed away with about 3,000 ewes and lambs.

Further downstream the river was reported to be running 15 miles (24 km) wide and at depths of up to 70 feet (21 m); despite the damage, pastoralists were jubilant at how quickly the grasses were growing.