Territory Stories

Alice Springs town basin, review 2003

Details:

Title

Alice Springs town basin, review 2003

Creator

Read, R. E.

Collection

E-Publications; E-Books; PublicationNT; Report ; no. 42/2003

Date

2003-12-01

Description

Made available via the Publications (Legal Deposit) Act 2004 (NT).

Notes

Date:2003-12

Language

English

Publisher name

Department of Infrastructure, Planning and Environment

Place of publication

Alice Springs

Series

Report ; no. 42/2003

File type

application/pdf.

Copyright owner

Check within Publication or with content Publisher.

Parent handle

https://hdl.handle.net/10070/229443

Citation address

https://hdl.handle.net/10070/672980

Page content

RN 5713 had a water level of 14.9 m in 1961 and 4.5 m in 1975. By 1975 this area was partly urbanised. This large change is interesting in view of the fact that there has been no significant extraction in this area. Irrigation leaching from the Braitling Oval, numerous private gardens and the usual leaking distribution systems must all have contributed to increased recharge and raised water tables. By analogy with the Town Basin direct recharge is likely to be in the range of 10 to 20 mm per year. Assuming an area of 2 km2, outflow from Braitling is around 20 to 40 ML/year. Some of this may be down the present channel of the Charles River, but most probably moves south through the former channel of the Charles to the west of Teppa Hill. Quinlan and Woolley (1969) indicate branches of the 1820, 1830 and 1840 aquifers that appear to come from this direction. Salt export would be in the range 40 to 200 T/y. No evidence of salinisation is known from this area. 6.4.3 Golf Course The hydrogeology of this area is poorly documented. Bores drilled in this area encountered saline water, which in some cases was not tested. Salinities of up to 9700 mg/L are known, from the marginal Town Basin sediments. The weathered bedrock to the east probably has water with salinity in the range 10 000 to 20 000 mg/L. Within the golf course some shallow piezometers (not entered as bores in the HYDSYS database) have been installed. Water levels under the greens range from 0.8 m to 0.2 m. The irrigation of greens over low permeability weathered rock and sediments has caused water tables to rise. 6.4.4 Heavitree Gap Area This area is the extreme southern part of the Southern Zone and the Figure 34 shows salinity trends in the Heavitree Gap Area. Locations for the bores are in Figure 35 . In the area near Heavitree Gap there has been an increase in salinity. However RN 3084 which is further upstream and in the sand aquifer has shown no significant change. Historically this area always showed considerable fluctuations in salinity, depending in part on flows on the Todd (see graphs for RN 7506, Appendix E). 57