On average South Australia uses 1165 GL of water per year, which is 5% of Australia's total use. Of the total water use, 746 GL of water is used from surface water sources and 740 GL of surface water is allocated to consumptive use.
419 GL of water is used from groundwater sources. The sustainable yield of groundwater for South Australia is 1146 GL per year which is 4% of Australia's total.
6 of the 34 Surface Water Management Areas and 21 of the 53 groundwater management units are assessed as being highly or overdeveloped.
Map of South Australia's surface water management areas
Select a surface water management area on the map to find out more about that area.
Map of South Australia's groundwater provinces
Select a groundwater province on the map to find out more about that area.
Water is a major factor influencing the development of South Australia.
Most of our population lives in the temperate, southern 15% of the State and even there major natural water resources are often removed from urban and industrial demand centres. As the State developed, demand outstripped local water sources and as new parts of the State were settled, major pipeline systems were constructed to transport water to demand centres.
The southern and coastal areas of the State receive annual rainfalls ranging between 300 mm and 1000 mm. It mostly falls in winter and early spring and streams flow as a result. In summer, evaporation is high and streams tend to become a series of pools and then dry up entirely.
In the remaining 85% of the State the climate is either semi-arid or arid. Rainfall occurs sporadically and can be concentrated and intense causing both local and widespread flooding. Evaporation rates are usually high and range up to extreme in the far north. Surface water dries out very quickly.
In their natural state, steams, floodplains and wetlands tend to be both abundant and diverse in flora and fauna. Occasional algal and bacterial concentrations occur naturally. Wetlands provide rich breeding sites and are refuges during dry periods. The natural ecosystems of stream beds, banks and floodplains depend on a wide range of stream flows and the steady contribution of groundwater where it is present.
Development often has adverse impacts on natural ecosystems. Monitoring has indicated that the health of water ecosystems in developed catchments has been degraded by pesticides, diffuse pollution, gross changes in natural stream channel configuration, riparian vegetation changes and altered stream flows.
The bulk of the State's surface water is fresh to marginally saline while high stream flows are often turbid. Surface water can be brackish when salt is flushed from drier catchments or is concentrated by summer evaporation. Streams in highly developed catchments - urban catchments for example - tend to have elevated concentrations of nutrients and heavy metals and are turbid. This degrades them for most uses. Streams in catchments covered with natural vegetation usually supply the best quality water.
Increased deep rainfall infiltration to groundwater has been a consequence of land clearing in agricultural areas. As groundwater levels rise toward the surface, widespread increases in soil salinity occur taking land out of production and increasing stream salinity. To some extent this process can be controlled locally by vegetation retention, water extraction and drainage.
In more than half the State groundwater is accessible all year round and, as a consequence, it is the major natural water source over much of SA. By nature, groundwater resources, which exist in shallow or confined porous media, or in fractured rocks, are extremely variable. Porous media aquifers generally provide the larger volumes of good quality water whereas fractured rock aquifers have characteristically lower yields. While low-yielding and localised in extent, fractured rock aquifers - which underlie 40% of the Australian continent - are often the only source of permanent water in the drier regions. Quantity and quality vary between regions. Large volumes of good water are available in some areas. In others it may be salty and difficult to access.
Apart from providing a resource in dry regions, groundwater discharging into streams in those areas can extend stream flow into summer and help sustain water-dependent ecosystems through dry periods.
Water is a finite and scarce resource in SA and the appropriate management response is to put in place arrangements that will ensure available water resources are used in an ecologically sustainable manner. Where State water resources are seen to be subject to increasing use pressures, or their environmental values are degrading, the Water Resources Act, 1997 allows the area to be proclaimed, users licensed and requires the implementation of water allocation plans to help regulate future development. The water allocation plans may also allow water rights or entitlements to be traded.
Surface Water Reporting Units
For this Audit, the basins as designated by the former Australian Water Resources Council (AWRC) have been adopted in South Australia as a reporting unit to maintain consistency with previous national water resources assessments. A number of these basins have been further subdivided to provide additional detail for areas warranting more intensive monitoring. All reporting units are referred to as Surface Water Management Areas (SWMA's) of which a total of 34 have been defined.
Groundwater Reporting Units
Groundwater abstraction, allocation and use information has been reported at three levels- Groundwater Management Units (GMUs), Unincorporated Areas and Provinces. Groundwater Management Units have been defined in accordance with the current groundwater management practices applied by the Department for Water Resources. Groundwater Provinces are based on the principle hydrogeological basins within South Australia. The Unincorporated Areas comprise the areas between the GMUs and the Province boundaries. In total 51 GMUs have been reported, including 15 Unincorporated Areas.
Only 23 of the GMUs are prescribed wells areas, which are the only areas within the State where allocations apply. In addition there are 3 Notice of Restriction areas which may be prescribed in the near future.
For further information contact South Australia Department of Water, Land and Biodiversity Conservation at http://www.dwlbc.sa.gov.au.
- View the South Australia Water Resources Assessment 2000 Report
- View the South Australia Water Resources Assessment 2000 Technical Report
- Link to data available for download on the:
- Surface Water Management Areas
- Groundwater management units and provinces - ARC/INFO export
- Data from the 1985 Review of Australia's Water Resources and Water Use
- Link to the Map Maker to make a map using this information.
Links to an another web site
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