South Esk River

South Esk
River
South Esk River in Launceston
Country	Australia
State	Tasmania
Region	Northern Tasmania
Part of	Tamar River
Tributaries
- left	River Tyne, Break O'Day River, St Pauls River, Meander River
- right	Nile River, Macquarie River, North Esk River
Source	Ben Lomond
- location	Mathinna Plains
- elevation	810 m (2,657 ft)
Source confluence	North Esk River
- location	Trevallyn
- elevation	0 m (0 ft)
- coordinates	41°43′16″S 147°13′06″E / 41.72111°S 147.21833°E / -41.72111; 147.21833
Mouth	Tamar River
- location	Launceston
- elevation	0 m (0 ft)
- coordinates	41°27′S 147°07′E / 41.450°S 147.117°E / -41.450; 147.117Coordinates: 41°27′S 147°07′E / 41.450°S 147.117°E / -41.450; 147.117
Length	252 km (157 mi)
Reservoirs	Lake Trevallyn
Location of the South Esk River mouth in Tasmania

The South Esk River, the longest river in Tasmania, is a major perennial river located in the northern region of Tasmania, Australia.

It starts in the eastern foothills of the Ben Lomond plateau near Mathinna and arcs around the entire southern promontory of the mountain - passing through Fingal, flowing through Avoca and Evandale before wending its way northwest through Longford and Hadspen. The river finally meets the Meander River and flows through the Cataract Gorge to meet the North Esk River at Launceston. From this point the river becomes the Tamar River and enters Bass Strait.

The river is dammed at Trevallyn Dam near Launceston as part of the Trevallyn Power Station. The river is constantly subject to flooding and overflows at Lake Trevallyn cause a scenic display of rapids gushing through the Gorge.

The river's two largest tributaries are the Macquarie River and the Meander River, with lesser tributaries being the Nile River, River Tyne, Storys Creek and the Break O'Day River upstream of the junction with the Macquarie River. The Meander's main tributaries are the Liffey River and Quamby Brook and the Macquarie's main tributaries are the Lake, Isis, Elizabeth, Blackman, and Tooms rivers.