Googong Dam
Coordinates35.420287°S 149.263086°E
CountryAustralia
LocationQueanbeyan, New South Wales
PurposeW
StatusO
Opening1977
OwnerCommonwealth of Australia
OperatorIcon Water
Dam crossesQueanbeyan River
Dam height66 m (217 ft)
Dam length417 m (1,368 ft)
Dam elevation crest663 m (2,175 ft)
Dam volume838 e3m3[a]
Spillway count2
Spillway capacity4,300 m3/s (150,000 cu ft/s)
Res nameGoogong Reservoir
Res capacity total119,400 ML
Res catchment873 km2 (337 sq mi)
Res surface696 ha (1,720 acres)
Res elevation659 m (2,162 ft)

The Googong Dam is an earth and rock-fill embankment dam comprising an adjacent saddle embankment across the Queanbeyan River, located upstream of Queanbeyan in the Capital Country region of New South Wales, Australia. The dam's purpose includes water supply for Canberra and Queanbeyan. The impounded reservoir is called Googong Reservoir.

The Googong Dam was created through enabling legislation enacted via the passage of the Canberra Water Supply (Googong Dam) Act, 1974.[1]

History

A green ban was briefly imposed by the Builders Labourers Federation for a few days until adequate assurances that marine life in Lake Burley Griffin would not be harmed.[2]

Location and features

Completed in 1977, the Googong Dam is a minor dam across the Queanbeyan River and Bradleys Creek and is located approximately 5 kilometres (3.1 mi) south of the city of Queanbeyan on the lower reaches of the river. The dam was built by Thiess Bros, based on designs developed by the Commonwealth Department of Construction; and is now managed by Icon Water.[3][4][5]

The main earth and rock-filled dam wall is 66 metres (217 ft) high and is 417 metres (1,368 ft) long. The adjacent earth-filled saddle dam is 13 metres (43 ft) high. When full, the resultant reservoir holds 121,083 megalitres of water, covers approximately 696 hectares (1,720 acres) that is drawn from a catchment area of 873 square kilometres (337 sq mi).[5] The concrete chute spillway is capable of discharging 4,300 cubic metres per second (150,000 cu ft/s).[3]

Successive flood events in 1978 and through the 1980s resulted in extensive erosion in the unlined section of the spillway chute, including a large erosion hole, up to 19 metres (62 ft) deep and 25 metres (82 ft) wide, in the upper part of the spillway chute. Staged remedial works were undertaken in the 1980s to protect the eroded structure. Remediation of spillway facilities occurred from 2006 through to 2010 that resulted in an increase in the capacity of the spillway, construction of walls in the spillway chute extension up to 17 metres (56 ft) high, and a range of other enhancements to meet extreme flood events.[5][6] In 2016, with more regular spillway overflows and to improve safety for waterway users, Icon Water installed a 240-metre (790-foot) floating safety barrier across the spillway, with a gate for authorised vessel access.

See also

References

  1. ^
  2. ^ Burgmann, Verity and Meredith (1998). Green Bans, Red Union: Environmental Activism and the New South Wales Builders Labourers' Federation. pp. 52–53.
  3. ^ "Register of Large Dams Australia-2015" (Excel. Requires download. Row 209). ANCOLD. January 2022. Retrieved 2026-03-05.
  4. ^ "Googong Dam". Water & Sewerage Systems: ACT Water Supply System: The Water Network: Water Storage. ACTEW Water. 2011. Archived from the original on 21 April 2013. Retrieved 17 April 2013.
  5. ^ "Googong Dam Spillway Upgrade". Projects. GHD Group. 2013. Archived from the original on 7 April 2014. Retrieved 17 April 2013.
  6. ^ "Googong Dam Spillway Remediation". Our Projects: Other Projects. ACTEW Water. 2011. Archived from the original on 10 April 2013. Retrieved 17 April 2013.
  1. ^ The main dam volume is 818 e3m3; the saddle dam volume is 20 e3m3.[3]