Hume Dam
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The Hume Dam is a dam in Australia, east of Albury-Wodonga, on the Murray River just downstream of its junction with the Mitta River, and when at full capacity banking water nearly 40 kilometres up both river valleys. The small towns of Tallangatta and Bonegilla are located on the shores of the resulting artificial lake, Lake Hume. Constructed of rock covered with clay and other earth, with a concrete spillway originally designed to carry vehicular traffic, the dam wall is 51 metres high and 1,616 metres long, and at 100% capacity can hold 3,000,000 megalitres of water.
A 50-megawatt hydro-electric power station is installed in the dam wall, and is primarily used for peak-load generation.
Constructed over a 12-year period from 1919 to 1931 with a workforce of thousands, it was extended during the 1950s, necessitating the wholesale removal of Tallangatta and its re-establishment at a new site eight kilometres west of the original.
As it is the furthest downstream of the major reservoirs on the Murray River system, and has the capacity to release water at the fastest rate, Lake Hume is used by the irrigation authorities as the storage of first resort. The reservoir typically falls to less than one-third capacity by March each year, but in normal years refills to at least two-thirds capacity before November, though Australia's highly unpredictable climactic conditions cause these figures to vary quite significantly from year to year.
Monitoring of the dam in the early 1990s revealed that the water pressure and leakage had caused the dam to move on its foundations slightly, leading to concerns that the dam was heading for collapse, threatening Albury-Wodonga and the entire Murray basin with it. Though authorities have denied any short-term threat, repair works have continued since, involving what appears to be construction of a second earth wall behind the original to take the strain. It is notable that the entire work force for the "repair" job is only a few dozen individuals, despite the task being of considerable magnitude.
The lake is stocked with fish. Most of these are imports - redfin and trout. The fishing varies from year to year. It is also popular for water skiing, and several holiday resorts catering for fishing and skiers are dotted around the upper reaches of the lake.