Water Resources of the Victoria River District
Tickell, S. J. (Steven); Rajaratnam, L. R. (Lakshman)
Northern Territory. Department of Lands, Planning and Enviroment. Water Resources Division
E-Publications; E-Books; PublicationNT; Report no. 11/1998
Victoria River Region
The aim of this study is to map, describe and evaluate the region's water resources. The project was started in 1993 at the request of the Victoria River District Conservation Association (YRDCA) and it was funded jointly by Landcare, the NT Government and the purpose is to provide pastoralists and communities with water resource information that will assist with property planning. VRDCA.
Groundwater -- Northern Territory -- Victoria River; Water-supply -- Northern Territory -- Victoria River; Water resources development -- Northern Territory -- Victoria River
Northern Territory Government
Report no. 11/1998
33 pages : illustrations and maps ; 30 cm.
Attribution International 4.0 (CC BY 4.0)
Northern Territory Government
https://hdl.handle.net/10070/672982 [Water Resources Survey of the Western Victoria River District - Water Resources of the Victoria River District_WRD98011.pdf]; https://hdl.handle.net/10070/672981 [Water Resources Survey of the Western Victoria River District - Water Resources of the Victoria River District_WRD98011.pdf]
Technical Report WRD98011 Viewed at 15:07:47 on 29/07/2010 Page 19 of 37. that recharge waters und.:rgo relatively little evaporation before they reach the watertable. This means that freestanding water bodies such as waterholes are not major recharge sources and infiltrating waters have a short residence time in the soil. RechafQe occurs bv ~ ~ ~ direct seepage of rainwater in areas wh.:re aquifers are exposed at the surface or by seepage through stream beds. Radiocarbon dates obtained for Qfoundwaters are all relativelv vounQ. Most are less than '- "r __ fifty years old and the oldest was only 3000 years, suggesting that the residence times for groundwater in the aquifers trom recharge are generally short. This is probably a ret1ection of the limited storage of the fractnred rock type aquifers of the VRD. The water level record trom the Rosewood bores also suggests limited aquifer storage capacity. Estimaks of recharge have been made from several sources. Long term average values "vere obtained by comparing chloride concentrations of groundwaters with those of rainwater. Values of 14 mm and 8 mm in the northern and southern VRO respectively are considered to be of the correct order of magnitude. On a more local scale analysis of the Rosewood data indicates that annual recharge can vary trom nothing to about 40 mm depending on the seasons rainfall. SURFACEWA TER There are numerous surface water sources and storages in the reQion. N:llural sources include ~ waterholes. lakes and springs. Various types of dams have been constructed including excavated tanks. ring tanks and embankment dams. Dams are relatively uncommon and tend to be built in those areas .. vhere groundwater is difficult to obtain. \Vaterholes are the most widdy used natnral water source. JUTERHOLES AXD LAKES Waterholes occur throughout the region in all of the major rivers but also in medium sized streams and creeks. ~'ifost of tbe major rivers. for example the Victoria. Negri amI East BaiDt~s Rivers and Swan Creek nom1ally now for about four to six months of the year. Stirling Creek tlows tor more than six months. For the balance of the year. they break up into chains of waterholes which !ast tor varying periods depending on their depth and whether or not they are spring fed. Even shallow ones may be permanent if they are supplemented by spring t1ows. examples indude S,van Creek Waterhole on Lilllbunya and Lowies \Vaterhole on Daguragu. Some waterholes pal1icularly those on the major rivers are permanent but most are seasonal. Waterholes form where there is a watertight rock base and where there is a rock bar acting as a dam. The Bulla community tor example obtains its water supply from a ,vaterhole \,\"itll a siltstone base in the East Bains River. 1nllle more rugged country, gorges are often the sites oflong deep waterholes such as in Bullo River and Jasper Gorges. They also foml on alluvial plains where impenneable clay rather than rock forms the base and where depressions have been scoured in the channel. Lagoons or billabongs are depressions in the beds of abandoned or partly abandoned river channels. Ring Lagoon on Auvergne for example is an ablmdoned meander of the Bains River. Only a few small lakes are lound in the VRD, notably Lake Nongra on Birrindudu and 1nver.vav. \Vatties Lake on \Vallamunga. Leslie's Lake on Bullo River and an unnamed lake ~ .- .... . on Legune near Bundaburg Bore. All of these are furmed on alluvial plains and are too shallow to be permanent. The most extensive of these. Nongra Lake becomes brackish as it dries up. 15