Adelaide
Physical information

General description

Area: 5,340 km²

Population: 1,350,000 (Australian Bureau of Statistics 2012)

The Adelaide region is located in the southeast of South Australia, on the east coast of the Gulf St Vincent (Figure P1). It extends from the Barossa Valley in the north to the Fleurieu Peninsula in the south, and includes metropolitan Adelaide, the Northern Adelaide Plains and the Western Mount Lofty Ranges (Figure P2). The terrain in the region ranges from flat plains near the coast to steep hills in the east and south.


Figure P1  Location map of the Adelaide region
Figure P1  Location map of the Adelaide region


Figure P2  Contextual map of the Adelaide region
Figure P2  Contextual map of the Adelaide region


The Adelaide region (Figure P2) is physically defined by the hydrological boundaries of the five main drainage basins located in the Adelaide region (Figure P3). These are based on their location (north to south) within the Adelaide region and include the following basins:

  • Part of the Gawler River drainage basin is located within the Adelaide region (4,460 km2 in total; 2,070 km2 or 46% within the Adelaide region). This includes the Gawler River, the North Para River, the South Para River and tributaries, which flow west from the northern Mount Lofty Ranges to the Gulf St Vincent. The Light River is located within the Gawler River drainage basin, but is not located with the Adelaide region (Figure P3).
  • River Torrens drainage basin (1,190 km2) includes the River Torrens and the Little Para River. The River Torrens flows from the Mount Lofty Ranges through Kangaroo Creek Dam to Adelaide and then to the Gulf St Vincent.
  • Onkaparinga River drainage basin (960 km2), which flows west from the southern Mount Lofty Ranges to Hahndorf, then through Mount Bold Reservoir to the Gulf St Vincent.
  • Myponga River drainage basin (155 km2), which flows into the Myponga Reservoir and then southwest to the Gulf St Vincent.
  • Fleurieu Peninsula drainage basin (1,050 km2) includes several smaller rivers, such as the Bungala and Yankalilla rivers, that flow west into the Gulf St Vincent and the Hindmarsh and Inman rivers that flow southeast into the Southern Ocean.

The Adelaide region approximates the Adelaide and Mount Lofty Ranges Natural Resources Management (NRM) Board region. The NRM region is approximately 10% larger than the Adelaide region as the boundary is modified to incorporate administrative boundaries (i.e. local council and property boundaries).


Figure P3  Map of surface water drainage basins in the Adelaide region
Figure P3  Map of surface water drainage basins in the Adelaide region


Scope of the Adelaide region water account

The Adelaide region water account includes water stored in and transactions related to:

  • surface water storages in the region
  • rivers within the region
  • water held in storages, pipes and infrastructure as part of urban water supply and wastewater collection systems
  • groundwater aquifers beneath the region
  • irrigation schemes within the region.

The Adelaide region water account excludes water stored in and transactions related to:

  • off-channel water storages, such as farm dams and private commercial water storages
  • estuaries
  • water held in the landscape, such as soil moisture, and water held in wetlands that are not connected to rivers.

For more information regarding items in this water accounting report, please refer to the Water accounting policies.

Land use

The dominant land use in the Adelaide region is agriculture and urban (Table P1 and Figure P4).

The major cities and towns in the region, along with their population, are (Australian Bureau of Statistics 2012):

  • Adelaide metropolitan area (including Gawler)—1,225,235
  • Nuriootpa—5,968
  • Victor Harbor—13,411.

There are five irrigation districts in the region with most irrigation water being self-extracted. There are three major irrigation schemes within the region that supply water for viticulture, horticulture and irrigated pasture.

Overall, manufacturing is not a large user of water in the Adelaide region although some manufacturers are locally intensive water users. Major water intensive industries include wineries, brewing, beverage production, food and fibre processing, concrete and soda production (Adelaide and Mount Lofty Ranges Natural Resources Management Board 2008; Zulfic et al. 2008).

Table P1  Land use in the Adelaide region
Land use Area (km2) Area (% of total)
Conservation and natural environments 718 14
Grazing 1,826 34
Forestry 160 3
Dryland agriculture 836 16
Irrigated agriculture 488 9
Urban 1,089 20
Other intensive uses 73 1
Mining 17 <1
Water 125 2
Total1 5,332

~

100

1 This area is less than the total region area reported in 'General description' above due to the spatial resolution of the land use data

Source: Australian Bureau of Agricultural and Resource Economics – Bureau of Rural Sciences 2010.

Figure P4  Map of land use in the Adelaide region
Figure P4  Map of land use in the Adelaide region

Significant aquatic ecosystems

The region contains several nationally significant wetlands listed in the Directory of Important Wetlands in Australia (Table P2).


Table P2  Nationally significant wetlands in the Adelaide region
Wetland Description

Cleland Perched Swamps

Ecosystems dependent on waterlogged and peat soils maintained by surface and groundwater inflows

Englebrook Reserve

Open forest and swamp ecosystems

Washpool Lagoon

Freshwater coastal lagoon

Onkaparinga Estuary

Estuarine ecosystem with tidal swamps

Port Gawler and Buckland Park Lake

Estuarine ecosystem on mud flats and mangrove swamps

Barker Inlet and St Kilda

Significant marine ecosystem on mud flats and mangrove swamps

Illawong Swamp

Ecosystems dependent on waterlogged and peat soils

Maylands Swamp

Stipiturus Conservation Park (Glenshera Swamp)

Gold Diggings Swamp

Congeratinga Swamp

Upper Boat Harbour Creek Wetlands

Upper Hindmarsh River Catchment

Water resources

Water used in the region comes from the following sources:

  • surface water including watercourses
  • groundwater
  • local catchment harvesting
  • River Murray water transferred into the region by pipeline
  • recycled stormwater and wastewater 
  • desalinated water produced at the Adelaide Desalination Plant.

Some surface water resources within the region are fully developed, while others have scope for further development. This is illustrated in a comparison of demand versus sustainable extraction limit for surface water management zones in the Western Mount Lofty Ranges Prescribed Water Resources Area (PWRA).

Groundwater resources are generally fully developed. Some groundwater resources of the Northern Adelaide Plains and Mt Lofty Ranges are considered to be overdeveloped. This is shown in a comparison of demand versus sustainable extraction limit for groundwater  PWRA.

Recycled stormwater and wastewater are used increasingly for agricultural and municipal irrigation, and industrial purposes. There is scope for further development of recycled water and there are policies are in place to support this development.

The transfer of desalinated drinking water to the Adelaide urban water system started in October 2011, providing a flexible, climate independent alternative water source to the surface water generated within the Adelaide region or transferred from the River Murray (see the Other water resources and systems section herein for more information).

Surface water

The Adelaide region surface water resources include the drainage basins described in the General description section of the 'Contextual information'.

Most of the flow within the region's drainage basins usually occurs from June – October, reflecting the rainfall pattern of the region, where mean annual rainfall is higher in May – October. Figure P5 shows the location of flow gauging stations on unregulated reaches of the North Para River, Onkaparinga River and Myponga River. Flow data collected at these stations were used to represent the seasonal flow patterns along these rivers in Figure P6.

Figure P5  Location map of selected flow gauging stations on the North Para, Onkaparinga and Myponga rivers within the Adelaide region
Figure P5  Location map of selected flow gauging stations on the North Para, Onkaparinga and Myponga rivers within the Adelaide region

 

Figure P6  Graph of mean monthly flows along the North Para, Onkaparinga and Myponga rivers and mean monthly rainfall for the Adelaide region
Figure P6  Graph of mean monthly flows along the North Para, Onkaparinga and Myponga rivers and mean monthly rainfall for the Adelaide region

Several surface water storages and weirs (operated by SA Water) are located on the rivers within the Adelaide region (see Figure P7). These storages and weirs are predominantly for urban water use. Other storages, located off river, are used exclusively to service the urban water treatment plants. These surface water storages and weirs are detailed in Table P3.

Figure P7  Map of surface water storages and weirs in the Adelaide region
Figure P7  Map of surface water storages and weirs in the Adelaide region

 

Table P3  Surface water storages and weirs capacity
Storage location Surface water storages Total storage capacity (ML) Dead storage (ML)
On river storages Kangaroo Creek Reservoir                                  19,000 300
Little Para Reservoir                                  20,800 188
Millbrook Reservoir                                  16,500 188
Mount Bold Reservoir                                  45,900 27
Myponga Reservoir                                  26,800 163
South Para Reservoir                                  44,800 310
Warren Reservoir                                    4,770 22
On river storages subtotal                                178,570                     1,198
Off river storages Barossa Reservoir 4,510 19
Happy Valley Reservoir 11,600 71
Hope Valley Reservoir 2,764 123
Onkaparinga Summit Reservoir 427 64
Off river storages subtotal 19,301 277
Weirs Barossa Weir 136 0
Clarendon Weir 320 2
Gorge Weir 24 0
Gumeracha Weir 200 0
Weirs subtotal 680 2
Total           198,551                  1,477 

Further information on the Adelaide region's storages, including current levels and volumes, is given on the Bureau of Meteorology's Water storage website. Note that the volumes reported on the Water storage website exclude the dead storage volumes, whereas the National Water Account includes them.

Groundwater

Groundwater is an important water resource in the Adelaide region for both irrigation and stock and domestic supply. The major groundwater resources are:

  • Northern Adelaide Plains and Central Adelaide (Adelaide Plains)—Tertiary 1 and Tertiary 2 aquifers
  • McLaren Vale—Port Willunga Formation and Maslin Sands aquifers
  • Barossa—upper, lower and fractured rock aquifers
  • Western Mount Lofty Ranges—fractured rock aquifers.

Groundwater generally flows west from the higher rainfall recharge areas in the Western Mount Lofty Ranges towards the St Vincent Basin (Stewart, Banks and Wilson 2009). Lateral inflow is the main mechanism for recharge of the coastal aquifers.

Significant areas of groundwater use and groundwater management areas are presented in Table P4.


Table P4  Significant areas of groundwater use and groundwater management areas in the Adelaide region
Groundwater area Groundwater management area Hydrogeology Primary use
Barossa Barossa PWRA Confined, unconfined and fractured rock aquifers Viticulture
Central Adelaide Central Adelaide Prescribed Wells Area (PWA)
Confined, unconfined and fractured rock aquifers Mixed horticulture, industrial, domestic, irrigation of recreational areas
Northern Adelaide Plains Northern Adelaide Plains PWA Mostly confined aquifers Mixed horticulture, industrial
McLaren Vale McLaren Vale PWA Confined, unconfined and fractured rock aquifers Viticulture, horticulture
Adelaide Hills Western Mount Lofty Ranges PWRA Mostly fractured rock aquifers Mixed horticulture, irrigated pasture, viticulture
Southern Fleurieu Peninsula Western Mount Lofty Ranges PWRA Mostly fractured rock aquifers with some confined and unconfined aquifers Mixed horticulture, irrigated pasture, viticulture

Other water resources and systems

Urban water system

The urban water system includes water and wastewater treatment plants, pipes and tanks. All of this urban infrastructure is operated by SA Water and is described in further detail in Table P5.


Table P5  Urban system infrastructure in the Adelaide region

Infrastructure

Operation

Major use

Mannum–Adelaide pipeline

Delivers untreated River Murray water for use by the Adelaide urban water system and the Barossa Infrastructure Limited irrigation scheme. Water for the urban water system is discharged into the River Torrens and the region's storages before diversion into the water treatment plants, or directly piped to the water treatment plants (WTPs).

Urban and irrigation

Murray Bridge–Onkaparinga pipeline

Delivers untreated River Murray water for use by the Adelaide urban water system. Water is discharged into the Onkaparinga Summit Reservoir and then the Onkaparinga River and other storages before diversion into the WTPs.

Urban

Swan Reach–Stockwell pipeline

Delivers treated River Murray water to the urban water system to supply the Barossa Valley and northern Adelaide as well as to urban areas outside the Adelaide region. May be used to supply Barossa Infrastructure Limited irrigation scheme in case of need.

Urban

Metropolitan Adelaide water supply system

Delivers potable water from the water treatment plants and the Adelaide desalination plant. Includes the North South interconnection system that allows transfers of water across the urban water system.

Urban

Metropolitan Adelaide wastewater system

Delivers wastewater to Adelaide wastewater treatment plants (WWTPs)

Urban

 

More information about the pipelines transferring water from the River Murray is available at South Australian Water Corporation (2010a).


The urban water infrastructure summarised in Table P5, including urban water supply area, WTPs, desalination plant, WWTPs and major pipes that are used to service the Adelaide region's urban water needs are depicted in Figure P8.



Figure P8  Map of urban water system infrastructure
Figure P8  Map of urban water system infrastructure




Table P6 lists the WTPs located within the geographic boundaries of the Adelaide region. Urban users in the Adelaide region are also supplied with water treated at the Swan Reach WTP and Mount Pleasant WTP, which are located outside the region.

 

Table P6  Water treatment plants in the Adelaide region
WTP Water source – reservoir
Anstey Hill Millbrook Tank
Barossa Barossa Reservoir
Happy Valley Happy Valley Reservoir
Hope Valley Hope Valley Reservoir
Little Para Little Para Reservoir
Myponga Myponga Reservoir
Summit Storage Summit Reservoir

More information about those water treatment plants is given at South Australian Water Corporation (2010b)..



Irrigation schemes

Three major irrigation schemes operate in the Adelaide region as described in Table P7.

Table P7  Major irrigation schemes operating in the Adelaide region
Irrigation scheme Location Water sources Purpose

Virginia Pipeline Scheme

public-private partnership between SA Water and Water Infrastructure Group

Services the Virginia and Angle Vale districts in the north of the Adelaide region Recycled water from the Bolivar WWTP Irrigation of 20 different crops including fresh vegetables
Barossa Infrastructure Limited
public company
Services the Barossa Valley The primary source of water is from the River Murray via the Mannum–Adelaide pipeline. River Murray water can also be supplied from the Swan Reach–Stockwell pipeline in case of need. Recycled water is received from the Nuriootpa Community Wastewater Management System (CWMS). Irrigation water for viticulture
Willunga Basin Water Company reclaimed water scheme owned and operated by its users Services the McLaren Vale region The primary source of water is recycled water from the Christies Beach WWTP. Recycled water is also received from the Aldinga WWTP and the Willunga CWMS. Predominantly irrigation water for viticulture, but is also used for irrigation of fruit trees, nut crops and flowers


Recycled wastewater

Recycling of wastewater is increasingly significant to the Adelaide region. Approximately 30% of the wastewater treated by SA Water is used in recycled water applications (Office for Water Security 2010). CWMSs, which harvest water from household septic systems, are another source of treated wastewater and are typically operated by local councils. The most significant recycled wastewater schemes in the Adelaide region are presented in Table P8.

Table P8  Recycled wastewater schemes in the Adelaide region
Recycling facility Capacity – approx Purpose Operator
Aldinga WWTP More than 390 ML/year Irrigation of vines SA Water
Bird-in-Hand WWTP 300 ML/year Irrigation SA Water
Bolivar WWTP 18,000 ML/year Mainly agricultural irrigation (Virginia pipeline scheme), some municipal irrigation and dual reticulation at Mawson Lakes SA Water, Allwater
Christies Beach WWTP 3,500 ML/year Irrigation of vines (Willunga Basin Water Company) and municipal irrigation
SA Water
Glenelg WWTP 3,800 ML/year Irrigation of parks and recreation facilities (Adelaide Park Lands pipeline) SA Water
Golden Grove Up to 280 ML/year (not yet supplying at capacity) Irrigation of parks and recreation facilities CWMS
Greenock, Kapunda, Freeling, Roseworthy 180 ML/year Irrigation of vines CWMS
Kersbrook, Birdwood/Mount Torrens, Charleston, Woodside, Verdun Unknown Irrigation of woodlands CWMS
Myponga, Yankalilla, Second Valley Unknown Irrigation CWMS
NPEC WWTP 250 ML/year Irrigation (reuse of winery wastewater) North Para Environmental Control (NPEC)
Nuriootpa, Lyndoch, Penrice, Mount Pleasant, Tanunda, Williamstown, Springton 700 ML/year Irrigation of vines CWMS
Other SA WTPs (e.g. Angaston, Gumeracha) Individual capacity <100 ML/year Irrigation SA Water
Victor Harbor WWTP 150 ML/year Irrigation of horticulture and parks SA Water
Willunga CWMS 340 ML/year Irrigation of vines and recreational facilities (Willunga Basin Water Company) CWMS operated by the City of Onkaparinga

(Barossa Council website; Kelly, Stevens & White 2003; Council staff at various councils, pers. comm.; SA Water unpublished WTP records 2010).


Stormwater harvesting

Stormwater harvesting (collection, treatment and use of urban runoff) is of increasing importance to the Adelaide region. The schemes are typically operated by councils and involve treating stormwater through constructed wetlands and storage in aquifers. Treated stormwater is generally used for irrigation of parks and ovals, and industrial processes, such as wool washing.

The current capacity of stormwater schemes is approximately 7,550 ML/year with many new schemes are under development (Adelaide and Mount Lofty Ranges Natural Resources Management Board 2012; Office for Water Security 2010; Stormwater Management Authority 2009 ).


Desalinated water

The first 50,000 ML/year desalination plant was completed during the 2011–12 year. The transfer of desalinated drinking water to the Adelaide urban water system commenced on 14 October 2011. 

Sea water is taken from the Gulf St Vincent and treated at the Adelaide Desalination Plant at Lonsdale. Desalinated water mixes with water treated at the Happy Valley WTP before entering the Happy Valley distribution network; however, the completed North South interconnection system project enables SA Water to deliver this desalinated water to customers in both Adelaide's northern and southern suburbs.  

At full capacity, the Adelaide Desalination Plant will be able to produce up to 100,000 ML/year of water1, about half of metropolitan Adelaide's annual water demand. In the future, however, the plant's production levels will vary depending on SA Water and plant requirements. The use of the desalination plant will be balanced with volumes stored in surface water storages and SA Water's River Murray licence to ensure customer demand is met in a sustainable and cost-effective manner. It is projected that the desalination plant could be placed in standby mode at the end of December 2014, subject to a review of the water supply situation in 2013-14. Under standby operation, the desalination plant will not produce water but will be maintained to a level where it can be brought online within a matter of weeks.

There are also more than 25 privately and publicly owned desalination plants with an individual capacity greater than 1.8 ML/year in the region. These desalination plants are typically used to improve groundwater, wastewater and mains water quality on a small scale to a standard suitable for irrigation, industry and medical purposes. Desalination of groundwater for food, beverages and industrial processes constitutes 95% of the capacity of the small scale desalination plants in the region.

1 The full capacity 100,000 ML/year plant was handed over for operation on 12 December 2012.


Off-channel water storages

Off-channel water storages are an important water resource in the Adelaide region. The region hosts in excess of 15,000 off-channel water storages holding more than 39,700 ML of water when full. On average, farm dams harvest around 10% of annual surface water flow, although on a seasonal basis this can be more than 70% in some catchments during the summer and autumn months.

The majority of off-channel water storages in the Adelaide region are filled by runoff from the landscape. Off-channel water storages filled by surface water diversions and groundwater extractions represent only a small proportion of off-channel water storage volume in the Adelaide region. Similarly, off-channel water storages in the Virginia and Angle Vale districts, which are filled from recycled water supplied by the Virginia pipeline scheme, also represent only small proportion of off-channel water storage volume in the Adelaide region.

Water held in and abstracted from off-channel water storages is used for a combination of purposes including industrial, irrigation, and stock and domestic purposes. In the Barossa PWRA, water from off-channel water storages is predominantly used for irrigation purposes (Barossa PWRA Water Allocation Plan: p26), whereas throughout the rest of the Adelaide region the majority of off-channel water services stock and domestic purposes (draft water allocation plan for the Western Mount Lofty Ranges PWRA: p63)


Mine, construction and quarry dewatering

Mine dewatering occurs in the Adelaide region to facilitate mining, quarrying and construction activities. Depending on water quality, the water is stored in above-ground storages, discharged into nearby watercourses or aquifers, or applied to the landscape. For example, Penrice dewaters the Angaston quarry within the Barossa PWRA (Golder Associates 2008).