The Liapootah Dam is a gravity dam across the Nive River, located in the Central Highlands region of Tasmania, Australia. Completed in 1960, the dam was built by Hydro Tasmania for the purpose of generating hydroelectricity. The resultant reservoir, Lake Liapootah, provides water for the Liapootah Power Station, a run-of-the-river hydroelectric power station.
Dam overview The concrete gravity dam wall is high and long. When full, the reservoir has capacity for and covers , drawn from a catchment area of . The controlled spillway has a flow capacity of . Water from the Derwent below the Tarraleah and Tungatinah power stations is diverted through a concrete lined tunnel.
Hydroelectric power station Part of the Derwent River scheme that comprises eleven hydroelectric power stations, the Liapootah Power Station is the first power station in the lower run-of-river system. The power station is located above ground, below Lake Liapootah.
Lake Liapootah is very narrow and is considered a run-of-the-river storage. During high inflow events the pond level can threaten the Tarraleah Power Station upstream. The drum gate is designed to lower automatically and maintain a maximum pond level below the flood level of Tarraleah station. Having the drum gate installed maximises the head at Liapootah station. The alternative to this would have been to build the dam at a lower level, thus reducing the available output from Liapootah station.
The power station was commissioned in 1960 by the Hydro Electric Corporation (TAS) and the station has three English Electric Francis turbines, with a combined generating capacity of of electricity. Within the station building, each turbine has a fully embedded spiral casing and water flow is controlled by a spherical rotary main inlet valve and a turbine relief valve designed to prevent spiral casing overpressure. The station output, estimated to be annually, is fed to TasNetworks' transmission grid via three banks of 11 kV/220 kV three-phase English Electric generator transformers to the outdoor switchyard.
See also
List of reservoirs and dams in Tasmania List of power stations in Tasmania List of run-of-the-river hydroelectric power stations
References
External links Hydro Tasmania page on the Derwent hydropower scheme