The Eildon Dam or Eildon Weir, a rock and earth-fill embankment dam with a controlled spillway across the Goulburn River, is located between the regional towns of Mansfield and Eildon within Lake Eildon National Park, in the Alpine region of Victoria, Australia. The dam's purpose is for the supply of potable water, irrigation, and the generation of hydroelectricity. The impounded reservoir is called Lake Eildon.
The Eildon Hydroelectric Power Station operated by AGL Energy operates during the irrigation season from August to May is governed mainly by release of water to meet irrigation demands, but it may also be operated during winter and spring when flood releases can be used to generate electricity. The power station can also be used to meet short term emergency power needs resulting from industrial disputes or plant breakdown elsewhere in the State's power grid. Initially completed as part of the Sugarloaf Reservoir with just 15 megawatts of hydro–electric generating power, capacity was increased in 1956 to 120 megawatts through the installation of two 60 megawatts turbines. The oldest turbines were renovated in 2001 to provide a generation capacity of 135 megawatts. A 5,200 megalitres pondage below the dam temporarily detains water discharged from the power station and regulates releases downstream to minimise variations in flow due to intermittent power generation. In 1995 a small hydro-electric station with 4.5 megawatts output was installed on the pondage.
Drought and recovery
During the drought years in Victoria in the 2000s, Lake Eildon rarely filled and the once-thriving holiday destinations around the lake were unable to attract visitors, leading to considerable economic hardship. Although water is in great demand for agriculture, careful regulation has kept outflows fairly static. During November 2006 the lake dropped to a low of only 15% from the previous year level of 48.3%. After many years with below average rainfall, 2010 saw Lake Eildon receive above average rainfall and rose from 23% of capacity in May 2010 to be 82.5% as of March 2011.
The container is a familiar object hidden in the lower reaches but just out of reach.