The Scotts Peak Dam, together with the Edgar Dam and the Serpentine Dam, are three major dams that form the headwaters for the Gordon River Power Development Scheme. The dam is located near Lake Pedder's most easterly point[5] in the upper reaches of the Huon River where the river descends from the Marsden Range and descends into what is now known as the Huon Basin. Also at the southern end of the Lake Pedder, the Scotts Peak Dam impounds the upper reaches of the Huon River. At the northwestern end of the lake is impounded by the Serpentine Dam across the Serpentine River. The water in Lake Pedder provides around 40% of the water used in the Gordon Power Station. The water flows to Lake Gordon via McPartlan Canal.[2] Water from Lake Gordon then exits through the Gordon Dam.
Built on a foundation of rock and soil, the Scotts Peak Dam wall was constructed with 584 thousand cubic metres (20.6×10^6 cu ft) of rockfill and faced with asphalt. The dam wall is 43 metres (141 ft) high and 1,067 metres (3,501 ft) long. At 100% capacity the dam wall holds back 2,937,930 megalitres (103,752×10^6 cu ft) of water. The surface area of Lake Pedder is 241,330 hectares (596,300 acres) and the catchment area is 734 square kilometres (283 sq mi). The dam wall does not have a spillway.[1]
The construction of Scotts Peak Dam was controversial as it was built to flood Lake Pedder and extend the reservoir for the Gordon Dam. A small greens movement was formed it response, which mobilised in the 1980s to stop the proposed Franklin River Dam.[6]
Problems
In the 2008 edition of Ticklebelly Tales engineers associated with the dam acknowledge that there were issues leaks as soon as it was built.[7][8][9]
Evidence of deformation is still current in the 2010s.
Climate
Due to its far south-western location, this site is frequently lashed by severe weather; with a mean annual wind speed of 27.1 kilometres per hour (16.8 mph), peaking at a mean of 32.9 kilometres per hour (20.4 mph) in September. Cloud cover is likewise extreme, with precipitation falling on 269 days of the year and as much as 27 days in July. Snow is a common occurrence throughout the year and can even occur in the summer.
Climate data for Scotts Peak Dam (1998–2023); 408 m AMSL; 43.04° S, 146.27° E
^Felton, Heather; Hydro Tasmania (2008), Ticklebelly tales and other stories from the people of the Hydro, Hydro Tasmania, ISBN978-0-646-47724-4 page 458 - John Wilkins and Bruce Cole mentioned in relation to design and problem solving in the early 1970s, as well as the 1974 identified large hole in the bitumen wall
^Cole, BA (1976), "Wave Wall Design for Scotts Peak Dam", Annual Engineering Conference 1976: Engineering 1976-2001, Institution of Engineers, Australia: 126–133, ISBN978-0-85825-058-1
^Roberts, GT; Cole, BA; Barnett, RHW (1975), "Engineering Geology of Scotts Peak Dam and Adjacent Reservoir Watertightness", Annual Engineering Conference 1975: Papers, Institution of Engineers, Australia: 152–159, ISBN978-0-85828-045-8
