1.1.5 Surface water hydrology and water quality

Summary

The Cooper subregion of the Lake Eyre Basin bioregion is located predominantly in the state of Queensland and partly in SA, and it intersects the Cooper Creek – Bulloo river basin and the Diamantina–Georgina river basin. The area of the Cooper subregion is 130,060 km2 of which 118,128 km2 (91%) is included in the Cooper Creek – Bulloo river basin and 11,932 km2 (9%) in the Diamantina–Georgina river basin.

Much of the Cooper subregion is part of the Cooper Creek – Bulloo river basin. Cooper Creek and the Thomson, Barcoo and Bulloo rivers are the major streams in this basin. The stream below the junction of Thomson and Barcoo rivers is known as Cooper Creek and is characterised by complex channel networks and numerous wetlands and waterholes. Floods occur infrequently on the floodplain of Cooper Creek. However, during a large flood, the area becomes a huge inland sea broken only by a few ridges and numerous stunted trees. Water quality information such as total phosphorus (TP), total nitrogen (TN), electrical conductivity (EC) and turbidity is scarce for this basin. EC levels are normally low and stable. Turbidity is high and subject to varying trends as a result of local influences.

Only a small proportion of the Cooper subregion is part of the Diamantina–Georgina river basin in the north-west. The Diamantina River originates in the north of Cooper subregion and flows through a series of wetlands, lakes and waterholes along its 1000 km length. The Diamantina River is one of the major watercourses in the Lake Eyre Basin and the major contributor of surface water to Lake Eyre. The flow regimes of the basin are dominated by late summer flow events resulting from highly variable monsoonal rainfall in the upper catchments. The rivers have greatly varying widths of active channel and floodplain. Floods are infrequent but during large events, floodwaters inundate thousands of square kilometres. There are no permanent water quality monitoring stations in the Diamantina–Georgina river basin. However, limited water quality data reported under the Lake Eyre Basin Rivers Assessment (LEBRA) program indicate low EC levels and high turbidity in this region.

Last updated:
5 January 2018
Thumbnail of the Cooper subregion

Product Finalisation date

2015

ASSESSMENT