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Case Studies 1. Kyeamba Creek 2. Liverpool Plains 3. Billabong Creek 4. Wanilla 5. Axe Creek 6. South Loddon Plains 7. Kamarooka 8. Lake Warden 9. Brymaroo Printing help |
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Kyeamba Creek
Location: Southern New South Wales, 5 km south of Wagga Wagga. Area: 600 km2. Rainfall: 650 mm, grading from 600 mm in the north to 800 mm in the south. Land use Dominated by cattle grazing, limited sheep, some irrigation of crops and vegetables in the higher country. Reference: Cresswell et al. (2001) Salinity The salinity issue in Kyeamba Creek is mainly associated with the high contributing salt load conveyed through the stream to the Murrumbidgee River. Dryland salinity also exists within the catchment as a result of local variation in the thickness of the surface alluvial aquifer (mainly along Kyeamba Creek), and due to the high salt store of the surface material at the head of streams (mainly in Livingstone Creek). Groundwater system There are two aquifers operating within Kyeamba Creek. The upper system is a surface alluvial aquifer that carries most of the main watercourses. The variability of the aquifer thickness creates local flow cells only a few kilometres long. These have local discharge areas that become saline due to evaporative concentration of near-surface water. The other aquifer is a deeper and more extensive intermediate scale fractured rock aquifer that underlies much of the area. Groundwater flow is generally northward, complementary with the direction of surface flow in the larger creeks, and the water levels in this aquifer are near the surface over the lower reaches of Kyeamba Creek near its confluence with the Murrumbidgee River. Management The two different systems require quite different approaches. In the local alluvial system, recharge reduction through the establishment of trees, for example, must be targeted at each local flow cell, rather than as a general coverage. Forestry planning is underway in this catchment, involving up to 13% of the catchment earmarked for commercial hard and softwood plantations over the next decade. If these plantations are targeted to influence local groundwater flow cells then some recovery of the present discharge sites may ensue. In the case of the larger-scale flows within the deeper, more extensive fractured rock aquifer, a more general recharge reduction strategy may be required. This is unlikely to be achieved by the planned area of plantation timber, but may be positively influenced through changed cropping and grazing practices. |
Click for large conceptual model 
Click for large map of groundwater discharge zones 
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| design & production by Talkin' Technical Communications | last updated: April 2002 |