Bulloo River

From Wikipedia, the free encyclopedia

Bulloo River
Origin Grey Range, western Queensland (Idalia National Park)
Mouth Bulloo Lake (ephemeral)
Basin countries Australia
Length 1580 km (981 mi)
Source elevation 290m (2600 ft) at source
Avg. discharge 20 m³/s (river usually dry)
Basin area 75,534 km²

The Bulloo River is an isolated drainage system in western Queensland, central Australia. It is the only river in this region not part of either the Murray-Darling Basin or the Lake Eyre Basin; instead it flows into a number of ephemeral lakes blocked by low hills from reaching either Lake Frome or the Paroo River. In its very lowest reaches, which extend to near Tibooburra in New South Wales, is a distributary known as Bella Creek. It is believed that in past wet periods the Bulloo has had connections to Lake Frome because its fish fauna resembles the Lake Eyre rather than the Murray-Darling Basin[1].

There are a number of tributaries that flow into the Bulloo in its upper reaches, the largest being Blackwater Creek. Low ranges prevent the lower reaches of the Bulloo from receiving significant tributaries.

Hydrologically, the Bulloo is very similar to the Darling River and Cooper Creek. It is usually completely dry except for water holes, but during years of strong monsoonal activity in the summer the Bulloo can flood heavily to discharges of more than 1000 m³/s, and annual flows of up to five times the mean[1]. In dry years annual rainfall can be as low as 100mm (4 inches) throughout the basin and years of zero runoff are not unknown[2].

Annual rainfall throughout the basin ranges from 330mm (13 inches) in the north to 200mm (8 inches) in the south, with the northward increase being due to higher falls in the summer. In the winter, rainfall is rare throughout the basin, with the average between April and October generally around 115mm (4.5 inches), though on extremely rare occasions such as 1920-1921 and 1956 the river has had a significant flood during the winter. Temperatures in the summer are extreme throughout except during monsoonal activity, with mean maxima around 38°C (100°F) in January and minina around 23°C (74°F). In the winter maxima remain warm, ranging from 20°C (68°F) in the south to 25°C (77°F) in the north, but frosts are not unknown at night.

The Bulloo basin is used almost exclusively for the extensive grazing of sheep and cattle. The only towns within the basin are the former opal mining town of Quilpie and further downstream Thargomindah. There is only one major protected area, Idalia National Park, in th entire basin, located right in the river's headwaters.

[edit] Notes

  1. ^ Brown, J. A. H. (John Alexander Henstridge); Australia's Surface Water Resources. ISBN 0644026170
  2. ^ Willcocks, Jacqui and Young, Phillip; Queensland's Rainfall History: Graphs of Rainfall Averages, 1880-1988 ISBN 0724239138