Lake Burragorang

Lake Burragorang
from the air (April 2006)
Coordinates	34°0′S 150°26′E / 34.000°S 150.433°E / -34.000; 150.433Coordinates: 34°0′S 150°26′E / 34.000°S 150.433°E / -34.000; 150.433
Type	Man-made water supply dammed reservoir
Primary inflows	Coxs, Kowmung, Nattai, Wingecarribee, Wollondilly and Warragamba rivers
Primary outflows	Warragamba River
Catchment area	9,051 square kilometres (3,495 sq mi)
Basin countries	Australia
Max. length	52 kilometres (32 mi)
Surface area	75 square kilometres (29 sq mi)
Max. depth	105 metres (344 ft)
Water volume	2,031 gigalitres (7.17×1010 cu ft)
Shore length1	354 kilometres (220 mi)
Surface elevation	110 metres (360 ft)
1 Shore length is not a well-defined measure.

Lake Burragorang is an Australian man-made water supply dammed reservoir.

Lake Burragorang is impounded by Warragamba Dam and is located in the lower Blue Mountains of New South Wales, within the Greater Blue Mountains Area World Heritage Site. The 2,031 gigalitres (7.17×10¹⁰ cu ft) lake collects water from the converged flows of the Coxs, Kowmung, Nattai, Wingecarribee, Wollondilly, and Warragamba rivers and their associated tributaries. The lake is the major water storage for greater metropolitan Sydney, and its dam wall is located approximately 60 kilometres (37 mi) southwest of the Sydney central business district.

Pre-lake history

Before the construction of the Dam, Burragorang Valley had been inhabited by white settlers since the 19th century. A number of farming towns (including the town of Burragorang) and coal mines were located in the area. All of these are now underwater.^[1]

Capacity

The reservoir's usable capacity is 2,027 gigalitres (7.16×10¹⁰ cu ft). Prior to April 2006, the usable capacity was 1,857 gigalitres (6.56×10¹⁰ cu ft), before the Deep Water Storage Recovery project was completed.

There are fears, however, that population pressures may stretch the reservoir's ability to furnish Sydney residents with needed water well into the 21st century.^[2] The city's population is rising by about 50,000 every year, and water restrictions were imposed late in 2003; a serious drought would complicate matters.

There have been times when the lake has been seriously depleted. Since it was last full in 1998 the Warragamba Dam catchment area experienced extremely low rainfall, and on 8 February 2007 the lake recorded an all time low of 32.5% of capacity, although this had returned to 60% by late 2008.^[3] To prevent any chances of water supply failure, the NSW State government approved the building of a Desalination plant at Kurnell to augment Sydney's water supply.

As of 1 March 2012 (2012-03-01) the dam level was at 94.6% and rising. It was predicted to overflow within a day.^[4]

In the upper left corner of the view (at right) looking roughly southeastwards are Sydney's western suburbs. A crooked corridor of development may also be seen leading through the forested mountains to Sydney suburbs of Katoomba and Blackheath (near the centre) and beyond.

Public access

Lake Burragorang from space, November 1985

Lake Burragorang is surrounded by a 3 kilometres (1.9 mi) wide exclusion zone to protect the integrity of the water supply; access into this zone is restricted. There are two access corridors for bushwalkers: Mount Mouin to Mount Cookem and Belloon Pass to Yerranderie.^[5] Limited public vehicle access is allowed on fire trail W4 from Sheahys Creek to Yerranderie.

Power station

A hydroelectric power station at Warragamba Dam begins operating once the level in the reservoir reaches to within 1 metre (3 ft 3 in) of full capacity. Its output is 50 megawatts (67,000 hp),^[6] but the dam water level has not been high enough for it to operate since 1998.

Statistical overview

See also

Wikimedia Commons has media related to Mountain Scenery, New South Wales.

• List of Blue Mountains articles

References

External links

• Sydney Catchment Authority - Warragamba Dam
• Sydney's Dam Levels - current statistics and graphs