Kalgan River

Kalgan River
Southern end of Kalgan River near Lower Kalgan Bridge
Country	Australia
Basin features
Main source	Stirling Ranges 199 metres (653 ft)
River mouth	Oyster Harbour, Albany, Western Australia
Basin size	2,562 km2 (989 sq mi)
Physical characteristics
Length	140 kilometres (87 mi)
Discharge	Average rate: 1.69 m3/s (53,000 ML/a; 60 cu ft/s)

The Kalgan River is a river in the Great Southern region of Western Australia.

The river is 140 kilometres (87 mi) long and, along with the King River, drains into Oyster Harbour. The lower 9 km of the river take the form of a drowned river valley with steep hillsides of forest and farmland, and the occasional outcrop of granite . The river's source is west of the Stirling Ranges. It rises north-west of Kendenup and flows generally southwards until it reaches Oyster Harbour about 10 km north-east of Albany. The Kalgan River is the region’s fourth largest river in terms of average annual flow (53,400 megalitres), and has the third largest catchment area (2,562 km²).

The upper reaches of the Kalgan River lie protected within the National Park. These tributaries are marginally saline to brackish, suggesting the levels of salinity are natural. The loss of catchment vegetation (66% of the catchment is cleared) has increased salinity levels downstream. The lower section of the Kalgan River is tidal; a rockbar at the Upper Kalgan bridge separates the upper section from the tidal lower section. The tributaries of the Kalgan River include Napier Creek, Boonawarrup Creek, Young River, Stony Creek and Gaalgegup Creek. The river flows through two pools of note: Meriwarbelup Pool and Noorubup Pool.

The Kalgan River was named the "Riviere des Francais" by the French Scientific Expedition in 1803, captained by French explorer Nicolas Baudin, in the ship Géographe, which anchored in what is now known as Frenchmans Bay, and was subsequently known as the "French River" by early settlers. The explorer Alexander Collie recorded the river as "Kal-gan-up" in April 1831. The name Kalganup is believed to be the Noongar word for "place of many waters". Kalganup is also thought to mean "place of fishes" and there are still the remains of Aboriginal fish traps to prove the point. The traps, known as the Albany Fish Traps have been situated here for at least the last 7,500 years.