Fed by the Pine Rivulet and Breton Rivulet, the original natural freshwater lake, much smaller in size than its current 176-square-kilometre (68 sq mi) surface area, was expanded as a result of the 1922 construction of Miena Dam #2 at its southern outflow into the Shannon River. This dam is considered to be of high heritage value by Engineers Australia.[3]
Miena Dam #2 created the once-famous Shannon Rise,[4] in the 500-metre section of the Shannon River between the dam and Shannon Lagoon. The hatching of thousands of caddis moths in early summer, attracted large numbers of trout and fishermen.
In 1967, a sloping-core rock-fill dam was built just downstream of Miena Dam #2 to increase the maximum-capacity level, destroying the Shannon Rise. It was raised a further six metres (twenty feet) in 1982,[5] causing Miena Dam #2 to be periodically submerged.
After Lake Pedder, the Great Lake is the state's third largest freshwater lake.[1] It is known for its fantastic fly fishing opportunities, particularly after a wet winter or spring when water levels are high, trout can be found ‘tailing’ in the shallow, flooded margins of the lake which provides excellent sight fly fishing.[6]
The nearby towns of Liaweenee and Miena are popular holiday shack destinations for local tourists, despite the area's reputation as being one of the coldest places in the generally mild-weathered state. During the winter months, when the weather is hardly conducive to camping, the population of these two small towns drops to two or three hundred. Parts of the lake surface have frozen during July in some years.
The Lake Highway or Highland Lakes Road runs along the west side of the lake and is sometimes snowed under in winter.
Jetson, Tim (1989) The roof of Tasmania : a history of the Central Plateau. Launceston, Tas. : Pelion Press. ISBN0-7316-7214-3
Tasmania. Hydro-Electric Commission (1925), The hydro-electric power of Tasmania : a description of the Great Lake Hydro-Electric Development and of the Tasmanian Electricity Supply System Published under authority, Hydro-Electric Department of Tasmania, Tait, Melbourne
