Onkaparinga River


The Onkaparinga River, known as Ngangkiparri in the Kaurna language, is a river located in the Southern Adelaide region in the Australian state of South Australia.

Course and features

The Onkaparinga River rises on the slopes of the Mount Lofty Range between Mount Torrens and Charleston and flows generally southwesterly, south of the Adelaide city centre, to reach its mouth at Port Noarlunga. The catchment area is over in area, and in part includes the protected areas of the Encounter Marine Park, the Onkaparinga River National Park, the Onkaparinga River Recreation Park and the Port Noarlunga Reef Aquatic Reserve. The river descends over its course.
The Onkaparinga River is the second major river within the Adelaide metropolitan area, after the River Torrens. It is a source of fresh water for Adelaide. Mount Bold Reservoir was constructed between 1932 and 1938 along a section of its path approximately inland. Much of its flow is diverted via a tunnel from the Clarendon Weir to the Happy Valley Reservoir, that in turn supplies some 40 per cent of Adelaide's water supply. Most years the flow to the reservoir is supplemented by water pumped from the River Murray via a pipeline from Murray Bridge.
Downstream from Mount Bold Reservoir is the Clarendon Weir. To maintain levels at Clarendon Weir, water is released only as required. The Onkaparinga Gorge extends from Clarendon to Old Noarlunga. An estuary extends from Old Noarlunga to the river's mouth between the suburbs of Port Noarlunga and Port Noarlunga South. The estuary is a significant breeding area for local marine fish species.
The Coast to Vines rail trail crosses over the river just west of where Main South Road crosses over. The Seaford railway line passes over the river on a elevated bridge which was built between 2011 and 2014.

Etymology

The name derives from the indigenous Kaurna word, Ngangkiparinga, which translates as 'The Women's River'.
In 1837 Surveyor General Colonel William Light named it Field's River, or the Field River, after Lieutenant William George Field RN of the brig Rapid, who carried out the first surveys in the vicinity of its estuary, but subsequent Governor George Gawler soon reinstated the Indigenous name. The first Europeans to explore its sources and the Onkaparinga Valley were the party of Dr. George Imlay and John Hill in January 1838.