| Tarwin | |
| Pushpin Map: | Australia Victoria |
| Pushpin Map Caption: | Location of the Tarwin River mouth in Victoria |
| Subdivision Type1: | Country |
| Subdivision Name1: | Australia |
| Subdivision Type2: | State |
| Subdivision Name2: | Victoria |
| Subdivision Type3: | Region |
| Subdivision Name3: | South East Coastal Plain (IBRA), South Gippsland |
| Subdivision Type5: | Local government areas |
| Subdivision Name5: | South Gippsland Shire, Baw Baw Shire |
| Length: | 36km (22miles) |
| Source1: | Strzlecki Ranges |
| Source2: | Tarwin River East Branch |
| Source2 Location: | near the locality of Dollar |
| Source2 Elevation: | 253m (830feet) |
| Source3: | Tarwin River West Branch |
| Source3 Location: | west of |
| Source3 Elevation: | 91m (299feet) |
| Source Confluence: | East and West branches of the Tarwin River |
| Source Confluence Location: | west of |
| Source Confluence Coordinates: | -37.9608°N 146.3339°W |
| Source Confluence Elevation: | 17m (56feet) |
| Mouth: | Anderson Inlet, Bass Strait |
| Mouth Coordinates: | -38.6842°N 145.8358°W |
| Mouth Elevation: | 0m (00feet) |
| River System: | West Gippsland catchment |
| Tributaries Left: | Wild Dog Creek (Victoria), Berry's Creek (Victoria), Wilkur Creek (Victoria) |
| Tributaries Right: | Stony Creek (Victoria), Bridge Creek (Victoria) |
| Custom Label: | National park |
| Extra: | [1] [2] |
The Tarwin River is a perennial river of the West Gippsland catchment, located in the South Gippsland region of the Australian state of Victoria. The Tarwin River is the primary river system within South Gippsland Shire and has a catchment area of approximately, predominantly rural with small pockets of residential land use. It flows south from the Strzlecki Ranges and discharges in the eastern reaches of Anderson Inlet, a shallow estuary connected to Bass Strait.
Formed by the confluence of the Tarwin River East Branch that drains the southwestern slopes of the Strzlecki Ranges from an elevation of and the Tarwin River West Branch that drains the southern slopes of the Strzlecki Ranges from a northerly point at an elevation of, the Tarwin River rises near the locale of Tarwin, west of .
The east branch of the river rises below the locale of Dollar, then heads north through Tarwin East and on to before heading south through a valley, breaking out on to cleared farmland north of where the river is up to wide with slow flowing water when not in flood; and then continues south. The west branch of the river rises as a number of tributaries on the southern slopes of the Strzelecki Ranges at the south of Mount Worth State Park. The western branch of the river flows through mostly steep, cleared farmlands, fed by six minor tributaries as it flows south, east of and towards Meeniyan, generally through flat and rolling farmland.[3] [4]
The two branches then form as the Tarwin River, and flows generally south and then west by south, joined by two minor tributaries, through flat open river flats, passing around Tarwin Lower, flooding many local roads and then flowing into an extensive estuary and reaching its river mouth, emptying into Andersons Inlet, which flows into Bass Strait, near the township of . The lower reaches of the Tarwin River can be affected by tidal influences. From its highest elevation including the east and west branches of the river, the Tarwin River descends over its combined 82km (51miles) course.[2]
In the Aboriginal Boonwurrung language the river is given two names: Tarwin, meaning "thirsty", and Toulerm, meaning "gum".
It is a popular fishing river, with the river running with a species of fish known as "elephant fish" every season.
The river was named from an Aboriginal word .[5]