Lake Meadowbank, located between Hamilton and Ouse in the upper Derwent Valley, will soon be lowered by two meters to allow for the replacement of the nearly 60-year-old spillway gates on top of the Meadowbank Dam.
The Meadowbank Power Station, which uses water from the River Derwent held in the Lake Meadowbank reservoir, generates 187 gigawatt-hours of hydroelectricity annually – enough to power the city of Hobart.
The spillway gates, which are controlled by hydraulic cylinders and measure 6 x 35 meters, hold back approximately 60 million tonnes of water when the lake is full.
They are a critical component in power generation and safety at the dam and are due for replacement.
Work on the first gate will begin this month, and the lake will be lowered an additional four meters in mid-March for testing of the new hydraulic cylinders and control system.
The replacement of the second gate will be completed next year.
During the maintenance work, the Dunrobin boat ramp will be temporarily closed and the lake is expected to return to normal levels by May.