Derwent

Derwent

 

Derwent-diagram

The hydropower potential of the Derwent catchment was realised in 1934 when construction began on the Derwent scheme. The last power station was commissioned in 1968.
 
There are two sections in the Derwent hydropower scheme - upper and lower. This is because of the difference in how the water is stored in the sections. Visually the scheme resembles a Y shape.
 
The upper section of the scheme uses larger deeper lakes than the lower section for water storage. The four main power stations in the upper section can release water as it is needed to generate electricity. The upper section is formed from the Nive River system in the east and Derwent River system in the west, making up the top of the Y.
 
The lower section is run-of-river, this means that water keeps on flowing creating a cascade effect down the river. There are six power stations in the lower section using the Derwent River water multiple times. The lower section forms the ‘tail’ of the Y.
Butlers Gorge Power Station
Date commissioned 1951
Generating capacity 12.20 MW
Number of Turbines 1
Type of Turbines Francis
Technical fact sheet (680.84 KB)

The power station is supplied by the water stored at Lake King William. It is at the top of the ‘Y’ on the western side. Water then flows to Tarraleah Power Station. 

Clarke Dam, which Butlers Gorge Power Stations sits at the foot of Inside the station Entrance to the station Historic gate at Clarke Dam The spillway at Clarke Dam The spillway and tailrace as seen from the top of Clarke Dam
Nieterana mini hydro
Date commissioned 2004
Generating capacity 2.20 MW
Number of Turbines 1
Type of Turbines Francis
Technical fact sheet (688.13 KB)

Nieterana is the Aboriginal name for little brother. This mini hydro station sits along side ‘big brother’ Butlers Gorge Power Station and was commissioned in 2004. Its power source is the previously unused water from Lake King William that goes into the Tarraleah No 2 canal.

Nieterana mini hydro building Nieterana mini hydro building with Clarke Dam in the background Nieterana mini hydro turbine
Lake Echo Power Station
Date commissioned 1956
Generating capacity 32.00 MW
Number of Turbines 1
Type of Turbines Francis
Technical fact sheet (970.73 KB)

Lake Echo sources water from, you guessed it, Lake Echo. It is the first power station on the eastern side of the ‘Y’. Water flows from Lake Echo to Dee Lagoon and on to Tungatinah Power Station. 

Lake Echo Power Station The penstock is the last step in bringing water to the power station Canals and flumes bring water from Lake to the penstocks
Tarraleah Power Station
Date commissioned 1938 - 1951
Generating capacity 90.00 MW
Number of Turbines 6
Type of Turbines Pelton
Technical Factsheet (829.92 KB)

Water flows from Butlers Gorge Power Station via a series of tunnels, canals and pipes to Tarraleah. The water drops 290 metres through penstocks (steel pipes) to the power station. The water from the station meets with water from Tungatinah and flows to Lake Liapootah.

Looking back at Tarraleah Power Station from the tailrace The sheer drop of the penstocks to the power station A flume which is part of the system which delivers water to the station A canal which is part of the system which delivers water to the station Pipelines looking down to surge towers The drop of the penstocks to the power station Tarraleah Power Station shows great engineering achievements
Tungatinah Power Station
Date commissioned 1953 - 1956
Generating capacity 125.00 MW
Number of Turbines 5
Type of Turbines Francis
Technical fact sheet (668.93 KB)

Through natural and man made means water is brought together from various lakes and lagoons to Tungatinah Power Station. Once through the station the water flow meets with water from Tarraleah and flows to Lake Liapootah.

Tungatinah Power Station from downstream Inside the station Entrance to the station Inside the station
Liapootah Power Station
Date commissioned 1960
Generating capacity 87.30 MW
Number of Turbines 3
Type of Turbines Francis
Technical fact sheet (767.55 KB)

This is the first power station in the lower run-of-river system. This is where the cascade effect of water begins. Water from Lake Liapootah runs through to Liapootah Power Station and continues to Wayatinah Lagoon. 

Liapootah Power Station Liapootah Dam The Liapootah Tunnel
Wayatinah Power Station
Date commissioned 1957
Generating capacity 38.30 MW
Number of Turbines 3
Type of Turbines Francis
Technical fact sheet (546.49 KB)

Water from Wayatinah Lagoon flows through to Wayatinah Power Station, continuing its run to Lake Catagunya. 

Turbines inside Wayatinah Power Station Penstocks that bring water to Wayatinah The Wayatinah surge tower
Catagunya Power Station
Date commissioned 1962
Generating capacity 48.00 MW
Number of Turbines 2
Type of Turbines Francis
Technical fact sheet (990.92 KB)

Lake Catagunya flows into Catagunya Power Station with the water running on to Lake Repulse.

Catagunya Power Station The flume that connects the Lake to the power station The flume looking towards the power station Catagunya Dam under construction Catagunya Dam nearing completion
Repulse Power Station
Date commissioned 1968
Generating capacity 28.00 MW
Number of Turbines 1
Type of Turbines Kaplan
Technical fact sheet (671.97 KB)

Water from Lake Repulse turns the turbines at Repulse Power Station. The river continues to Cluny Lagoon.

Repulse Power Station A panorama of the power station and dam The power station viewed from the dam wall The curved dam wall
Cluny Power Station
Date commissioned 1968
Generating capacity 17.00 MW
Number of Turbines 1
Type of Turbines Kaplan
Technical fact sheet (621.66 KB)

Cluny Lagoon flows into Cluny Power Station. The cascade continues - water runs on to Lake Meadowbank.

Cluny Dam and Power Station Cluny Power Station Cluny Dam on spill with Hydro Tasmania staff looking on Showing the size of one of our smaller power stations The dam, power station and Cluny Lagoon in the background
Meadowbank Power Station
Date commissioned 1967
Generating capacity 40.00 MW
Number of Turbines 1
Type of Turbines Kaplan
Technical fact sheet (594.24 KB)

Meadowbank Power Station is the last in the run-of-river system. Water continues its journey in the Derwent River and eventually out to sea.

Meadowbank Power Station and dam Inside Meadowbank Power Station, count the ladders down to see how big the turbine is! Meadowbank Power Station The multiple arch Meadowbank Dam Lake Meadowbank held back by Meadowbank Dam