Crotty Dam
Background
The Crotty Dam was completed by the Hydro Electric Commission in 1991 as part of the King River Hydro Electric Scheme. It is a concrete faced rockfill dam and is unusual in having a spillway chute on the downstream face.
The dam is in a very scenic area, adjacent to the World Heritage Area, with extensive view of the surrounding wilderness areas. Great care was taken to minimise any environmental damage.
Extensive work areas for the dam and tunnel are now hidden under the impounded Lake Burbury.
The dam is near the site of Crotty township which died overnight when the Mount Lyell Mining and Railway Co took over the failing and over capitised North Mount Lyell Copper Coy. Most activities were transferred to Queenstown.
Equipment and Subsequent History
The dam is a concrete faced rockfill design and is unusual in having a spillway chute on its downstream face. Flexible joints in the chute allow it to adjust to long term movements of the underlying fill without cracking. The chute can pass flood waters of up to 240 cubic metres per second, thereby allowing time for the large valve to the diversion tunnel to be opened.
From Lake Burbury, water is carried through the West Coast Range in a 7km long headrace and power tunnel to John Butters Power Station before discharging back into the King River.
John Butters power station has a single 163MW Francis turbine.
Engineering Heritage Recognition Program
| Marker Type | National Engineering (NEM) |
| Award Date | 2001 |
| Heritage Significance | One of 25 Australia dams with the highest heritage value. A rigid structure with hinges to accommodate ground movement. |
| Nomination Document | Nomination document |
