History In the 1910s the
Mount Lyell Mining & Railway Company had investigated and surveyed a site very close to this dam for a proposed hydro electric scheme.
Charles Whitham also wrote of the inevitability of the dam in 1927 and even proposed "Lake Dorothy" as a name for the reservoir. Construction of the dam commenced in the 1980s following the
Franklin Dam controversy, and the reservoir was flooded in 1991. The dam was named in honour of
James Crotty who founded the North Mount Lyell Copper Mine at the turn of the 20th century. A ghost town site of the eponymous
Crotty was submerged by the waters of Lake Burbury; as was the settlement of
Darwin.
Technical details The Crotty Dam, together with the
Darwin Dam, are two major dams that form the headwaters for the King River Hydroelectric Power Development. The dam is located in the upper reaches of the King River gorge where the river breaks through the
West Coast Range. It captures the high rainfall in the catchment of the King River and allows diversion of water through a tunnel to the John Butters Power Station downstream of the dam. The concrete-faced
rock-filled dam wall is high and long. When full, Lake Burbury has capacity of and covers , draw from a
catchment area of . The single
controlled and uncontrolled spillway is capable of discharging .
Spillway The spillway is located on the embankment, rather than on one of the rock abutments. This unique spillway approach had never been successfully attempted before in the design of dams of any significant height, due to problems in making allowance for embankment settlements. In the case of the Crotty Dam, the embankment was partly composed of well graded gravels, and thus a very high modulus of embankment deformation was achieved. The high modulus limits embankment settlements. Additionally, the spillway was designed to articulate in order to accommodate any settlement that
did occur and to allow sufficient time for a large jet flow valve located in the diversion tunnel to be opened so that larger floods can be safely handled. The spillway designers, Sergio Giudici, also the chief engineer on the
Gordon Dam, Frank Kinstler, Steven Li, Tony Morse and Graeme Maher were acknowledged within the engineering community because the spillway was the first known to provide for articulation of the spillway structure so that movements in its foundations could occur without damage to the overlying structure. In 2001,
Engineers Australia selected Crotty Dam as one of the 25 dams with the greatest Australian heritage value and it was awarded a Historic Engineering Marker as part of the
Engineering Heritage Recognition Program.
Reservoir Named in honour of
Stanley Burbury, a former
Governor of Tasmania, Lake Burbury is fed mainly by rivers from the north, including the upper King, Nelson, Princess, and Eldon rivers that drain the
West Coast Range and include the
Linda Valley. A natural lake, known as
Lake Beatrice, lies just north of the reservoir's northern shore which is below the eastern end of
Mount Sedgwick. Part of the reservoir is crossed by the Bradshaw Bridge to connect with the
Lyell Highway. When it was impounded, the historical sites of Crotty and Darwin were flooded, the bridge of the
North Mount Lyell Railway over the King River was not salvaged, and significant portions of the
Kelly Basin Road were inundated. The dam and its reservoir were identified as "indicative places" on the (now defunct)
Register of the National Estate.
Recreation The reservoir is popular for fishing and anglers should be aware that the area is susceptible to extreme weather. A
webcam is located on the south east shore of the lake which looks across to where the Lyell Highway emerges from the Linda Valley and moves south around the eastern base of
Mount Owen and vision of fishing conditions may be viewed remotely. The reservoir lies to the west of the
Franklin-Gordon Wild Rivers National Park and has a series of buffer zone conservation areas; the Princess River Conservation Area and the Crotty Conservation Area on the east shore, and the West Coast Range Regional Reserve on the west. Access to the reservoir's shore is limited below , which is above the full supply level of . Access is also restricted on the island created by the impoundment. == Hydroelectric power station ==