The Cethana Dam is a concrete-faced rockfill embankment dam across the Forth River, located near in northern Tasmania, Australia. Completed in 1971, the resultant reservoir, Lake Cethana, was established for the purpose of generating hydro-electric power via the Cethana Power Station, a run-of-the-river hydroelectric power station.
The dam, its reservoir, and the power station are owned and operated by Hydro Tasmania.
Dam and reservoir overview Built between 1967 and 1971, the concrete-faced rock-filled dam wall is high and long. When full, Lake Cethana has capacity of and covers , drawn from a catchment area of . The single uncontrolled spillway is capable of discharging .
The Cethana Dam is listed as a National Engineering Landmark by Engineers Australia as part of its Engineering Heritage Recognition Program.
Hydroelectric power station
The Cethana Power Station is part of the MerseyForth scheme that comprises seven run-of-the-river hydroelectric power stations and one mini-hydro power station. The sixth station in the scheme, the Cethana Power Station is located underground and is supplied with water from Lake Cethana, from the Wilmot Power Station located below Lake Gairdner, and uncontrolled flow from the Forth River. Water from the Cethana power station is returned to the Forth River through a tailrace tunnel which has a tailrace gate structure at the outlet portal.
The power station was commissioned in 1971 by the Hydro Electric Corporation (TAS) and the station has one Fuji Francis-type turbine, with a generating capacity of of electricity. The station output, estimated to be annually, is fed to the outdoor switchyard via a three single-phase 13.8 kV/220 kV Fuji generator transformer.
Proposed pumped-storage station In 2023, under the Environment Protection and Biodiversity Conservation Act 1999 (Cth), Hydro Tasmania, as part of their Battery of the Nation initiative, submitted to the Australian Government approval of a proposed underground pumped-storage hydroelectric plant. It was proposed that the plant use the existing Lake Cethana as a lower storage reservoir and that it be connected, via underground tunnels and a new underground power station, to a new off-stream embankment dam with capacity of covering approximately , located above the western side of the existing reservoir. Additional transmission lines and a switchyard were also proposed. In April 2025, Hydro Tasmania decided to cancel the project.
See also
List of power stations in Tasmania List of reservoirs and dams in Tasmania List of run-of-the-river hydroelectric power stations
References