By rosebell
Following completion of the intake tower digging process, Hydro Tasmania has marked a major landmark on upgrades to the Tarraleah hydropower scheme.
With the aim of creating the deep excavation where the new concrete tower is going to be constructed, around 250,000m3 of rock and soil were removed. The past 27 months was the time that Tasmanian company Hazell Bros Group delivered the works.
In oreder to protecting the deep excavation from seepage from Lake King William, a plastic concrete cut-off trench was designed by power and water consultancy Entura, whereas it also provides flexibility for construction and timing of future works associated with the intake excavation.
According to Hydro Tasmania’s interim executive general manager, construction, Tammy Chu: “It was an exciting time for the upgrade works project. This has been an impressive effort, removing 240,000m3 of rock and soil and using 3,700 rock bolts (some up to 6m long). We overcame challenges with complex geology and typical Tassie winter weather, plus local jobs were created, with a peak workforce of 30 people on the ground delivering this work.”
While the next scheduled phase of work is the intake tower construction, a tender was released recently.
A 30m-high concrete structure housing intake screens, a large steel gate as well as associated hydraulic hoist, are the contents of this intake project that has been designed by Entura.
Linking the new intake to a future new conveyance to feed water into Tarraleah Power Station, work on the 950m connecting tunnel is also well advanced. For completing almost 260 blasts, removing 100,000 tonnes of material along the tunnel length, Hazell Bros Group is working alongside Tunnelling Solutions.
The 1930s was the date of building Tarraleah hydropower plant in Australia’s southern-most state.
Chu also added: “Hydro Tasmania is proposing a major redevelopment, so Tarraleah will be ready to help meet the growing demand for energy and power the state for generations to come.”
The Federal Government has committed up to A$65m (€37.6m) in funding for the upgrade works.
