Lachlan River

Infobox River
river_name = Lachlan River


caption = The Lachlan River at Cowra
origin = east of Gunning
mouth = confluence with the Murrumbidgee River near Oxley
basin_countries = Australia
length = 1450 km (901 mi)
elevation =
discharge = averages 40 m³/sec but extremely erratic
watershed = 84,700 km²

The Lachlan River is a significant river in central New South Wales, Australia.

Course

The river rises in the central highland of New South Wales, part of the Great Dividing Range, 13 km east of Gunning. Its major headwaters, the Carcoar River, the Belubula River and the Abercrombie River converge near the town of Cowra. Minor tributaries include the Morongla Creek.

Wyangala Dam was built near Cowra to regulate the flow of the river. However, the Lachlan, unlike the Murrumbidgee River and the Murray River further south, does not have its source in the snowfields and does not enjoy the large and reliable spring flow from the melting snow from which those rivers benefit. Indeed, the annual flow of the Lachlan is too erratic for really reliable dams to be possible. Annual flows have ranged from less than 1,000 megalitres (810 acre-feet) in 1944 to as much as 10,900,000 megalitres (8.8 million acre feet) in 1950. In dry years, the Lachlan can have periods of "zero flow" of over a year (for example from April 1944 to April 1945), which is a complete contrast to the Murray and Murrumbidgee which have not been known to cease to flow since European settlement. The river has flooded every seven years since 1887 at Forbes.cite web | year = 2007 | url = http://forbes.local-e.nsw.gov.au/roads/1095/1107.html | title = Flood management: Effects of Flooding in Forbes | work = Engineering Services | publisher = Forbes Shire Council | accessdate = 2007-09-18] The Lachlan River flows west and then south, terminating in the Great Cumbung swamp near Oxley (between Hay and Balranald). The 500 km² swamp, a floodplain for the Lachlan, joins the Murrumbidgee River to the south. There is some irrigation in the middle reaches of the Lachlan.

History

The Lachlan river is within the area occupied by the Wiradjuri people.cite web | year = 2005 | url = http://www.lcwl.org.au/lachlanregion.php | title = Landcare in the Lachlan Catchment| work = | publisher = Landcare | accessdate = 2007-09-18] The Wiradjuri tribal area has been described as "the land of the three rivers, the Wambool later known as the Macquarie, the Kalare later known as the Lachlan and the Murrumbidgee (Murrumbidjeri). The Murray River formed the Wiradjuri's southern boundary, the change from woodland to open grassland formed their eastern boundary." [ Mary Coe, in her book "Windradyne: A Wiradjuri Koori" quoted at page 4 in cite web | last = Patrick | first = Kathy | authorlink = | coauthors = Samantha Simmons | year = 1994 | url = http://www.austmus.gov.au/ahu/pdf/wiradjuri.pdf | title = Australian Museum's Aboriginal Collections: Wiradjuri | format = pdf: 39 pages | work = | publisher = Australian Museum | accessdate = 2007-09-18 ]

The European discoverer of the Lachlan River in 1815 was Acting-Surveyor George William Evans, who named the river after Lachlan Macquarie, the Governor of the colony of New South Wales. The Lachlan River was substantially explored by John Oxley in 1817. [Reed, A. W., "Place-names of New South Wales: Their Origins and Meanings (Reed: 1969).]

In the early days of the colony of New South Wales, the southern part of the Lachlan was known as "Fish River". It was only after further exploration that it was realised that these two rivers were the same river and the name Fish River was dropped.

In 1870 the river peaked at 15.9 metres at Cowra.cite web | year = 2001 | url = http://emergencynsw.hail.noggin.com.au/media/99.pdf | title = New South Wales State Flood Plan | format = pdf | work = sub plan of the State Disaster Plan | publisher = State Emergency Management Committee | accessdate = 2007-09-18] Since 1887, the highest flood level at Forbes was in June 1952 when the river peaked at 10.80m (35 feet 3 inches) at the Forbes Iron Bridge. More than 900 families were evacuated, with many rescued from roof-tops by boat and helicopter. [cite web | url = http://www.ema.gov.au/ema/emadisasters.nsf/6a1bf6b4b60f6f05ca256d1200179a5b/d5930dc0fdb46704ca256d33000581e9?OpenDocument | title = Central-Western NSW: Flood | work = EMA disasters database | publisher = Emergency Management Australia | accessdate = 2007-09-18] During the flood in August 1990, 132 houses in Forbes were affected by flood with their yards or their floors covered by water. Floods in 1992 did not reach the same levels at Forbes as in 1990, however, Lachlan Valley farmers lost about 30 percent of their lucerne crops just before harvest. At least 500 sheep were drowned on properties in the Eugowra/Trundle area and most of Eugowra's 400 residents were evacuated and some residents from Trundle. [cite web | url = http://www.ema.gov.au/ema/emadisasters.nsf/6a1bf6b4b60f6f05ca256d1200179a5b/8fc077c50a2395b7ca256d3300058047?OpenDocument | title = Widespread NSW: Flash Floods | work = EMA disasters database | publisher = Emergency Management Australia | accessdate = 2007-09-18] Other significant years of floods were: 1891, 1916, 1951, 1956, 1961, 1974, 1976, 1993, 1998. [cite web | url = http://www.naturalresources.nsw.gov.au/floodplains/risk.shtml | title = Flood risk in NSW | format = | work = Floodplains | publisher = NSW Department of Natural resources | accessdate = 2007-09-18 ]

Economy

More than 100,000 people live in the Lachlan catchment. 14% of NSW agricultural production is generated in the region from a land area of approximately 10% of NSW. 24 local government organisations provide administration within the region.cite web | url = http://www.lachlan.cma.nsw.gov.au/catchment.html | title = The Catchment | work = | publisher = Lachlan Catchment Management Authority | accessdate = 2007-09-18]

ee also

Major tributaries

* Abercrombie River
* Boorowa River
* Belubula River
* Crookwell River

Towns

*Breadalbane
*Bevandale
*Reids Flat
*Wyangala Dam
*Darbys Falls
*Cowra
*Gooloogong
*Paytens Bridge
*Tomanbil
*Forbes
*Jemalong
*Bedgerebong
*Waroo
*Fairholme
*Condobolin
*Gunebang
*Eubalong
*Hillston
*Booligal
*Oxley

References

External links

* [http://www.epa.nsw.gov.au/ieo/Lachlan/map.htm Map of the Lachlan River catchment]
* [http://www.lachlan.cma.nsw.gov.au/catchment.html Lachlan Catchment Management Authority website]