Adelaide
Physical information

Area: 5,350 km²

Population: Approximately 1.3 million (Australian Bureau of Statistics [ABS] 2011a, 2011b, 2011c).

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 P2 Contextual and catchment boundary map of the Adelaide region

The Adelaide region is physically defined by the hydrological boundaries of the following catchment areas, from north to south (refer Figure P2):

• 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 (2,095 km²) .
  
• The River Torrens, which flows from the Mount Lofty Ranges through Kangaroo Creek Reservoir to Adelaide and then to the Gulf St Vincent and the Little Para River (1,135 km²).
• The Onkaparinga River, which flows west from the southern Mount Lofty Ranges to Hahndorf, then through Mount Bold Reservoir to the Gulf St Vincent (930 km²).
• Myponga River, which flows into the Myponga Reservoir and then southwest to the Gulf St Vincent (153 km²).
• The Fleurieu Peninsula, which 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 (1,037 km²).

The Adelaide region water accounting statements include 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 systems
• groundwater aquifers beneath the region
• irrigation schemes within the region.

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

• off-channel water storages, such as farm dams and private commercial water storages; however, as farm dams represent an important water resource in the Adelaide region, information on off-channel water stores and transactions is presented in the Water resources and systems note
  
• 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.

The dominant land use in the Adelaide region is agriculture, including grazing and urban (Table P1 and Figure P3).

The major population centres in the region are:

• Adelaide metropolitan area (including Gawler)—1,225,235 (ABS 2011a)
• Barossa region—33,199 (ABS 2011b)
• Fleurieu Peninsula—46,350 (ABS 2011c).¹
  

¹ This estimate includes population estimates for Kangaroo Island, which is not part of the Adelaide region; however, this number is expected to be small in comparison to the total population for the Fleurieu Peninsula area.

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 NRM Board 2008; Zulfic et al. 2008).

Table P1  Land use in the Adelaide region¹

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
Total2	5,332

¹ Source: Australian Bureau of Agricultural and Resource Economics – Bureau of Rural Sciences 2010.

² This area is less than the total region area reported in 'General description' above due to the spatial resolution of the land use data

Figure P3  Map of land use in the Adelaide region

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 used in the region comes from the following sources:

• surface water including watercourses
• groundwater including managed aquifer recharge
  
• 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 Prescribed Wells Area (PWA) and Mt Lofty Ranges are considered to be overdeveloped. This is shown in a comparison of demand versus sustainable extraction limit for groundwater  in the Western Mount Lofty Ranges PWRA.

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

The Adelaide Desalination Plant provides a flexible, climate-independent alternative water source to the surface water generated within the Adelaide region or transferred from the River Murray (see the Desalinated water section for more information).

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 and potential evapotranspiration pattern of the region, where mean monthly rainfall is higher in May–October and potential evapotranspiration is low. Figure P4 shows the location of representative flow gauging stations on unregulated reaches of the North Para, Onkaparinga and Myponga rivers. Flow data collected at these stations were used to represent the seasonal flow patterns along these rivers in Figure P5.

Figure P4  Location map of selected flow gauging stations on the North Para, Onkaparinga and Myponga rivers within the Adelaide region



Figure P5  Graph of mean monthly flows along the North Para, Onkaparinga and Myponga rivers and mean monthly rainfall for the Adelaide region

Surface water storages and weirs operated by SA Water and used for urban water supply are detailed in Figure P6 and Table P3.



Figure P6 Map of surface water storages and weirs in the Adelaide region

Table P3  Surface water storages and weirs capacity

Surface water storage type	Name	Total storage capacity (ML)	Dead storage (ML)	Purpose
Reservoir1	Kangaroo Creek Reservoir	19,000	300	urban supply
	Little Para Reservoir	20,800	188	urban supply
	Millbrook Reservoir	16,500	188	urban supply
	Mount Bold Reservoir	45,900	27	urban supply
	Myponga Reservoir	26,800	163	urban supply
	South Para Reservoir	44,800	310	urban supply
	Warren Reservoir	4,770	22	urban supply
	Barossa Reservoir	4,510	19	urban supply
	Happy Valley Reservoir	11,600	71	urban supply
	Hope Valley Reservoir	2,764	123	urban supply
	Onkaparinga Summit Reservoir	427	64	urban supply
	Subtotal	197,871	1,475
Weir2	Barossa Weir	136	0	divert water for urban supply
	Clarendon Weir	320	2	divert water for urban supply
	Gorge Weir	24	0	divert water for urban supply
	Gumeracha Weir	200	0	divert water for urban supply
	Subtotal	680	2
Total		198,551	1,477

^1-2 According to the National Water Account Glossary reservoirs are reported at line item 1.1 Storages and weirs are reported at line item 1.2 Unregulated river

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.

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 Prescribed Water Resources Area (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

The Adelaide Desalination Plant, located at Port Stanvac (Figure P7), treats sea water taken from the Gulf St Vincent, providing an additional, climate-independent water source. Desalinated water is mixed with water treated at the Happy Valley Water Treatment Plant (WTP) before entering the Happy Valley distribution network. 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.  

The Adelaide Desalination Plant is able to produce up to 100,000 ML/year of water, which is about half of metropolitan Adelaide's annual water demand; however, the plant's production levels will vary depending on customer demand, impacts on other water resources and emergency responses (i.e., in response to flood events).  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.

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.

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
Mannum–Adelaide pipeline	Delivers untreated River Murray water to the 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 WTPs, or directly supplied to the WTPs.
Murray Bridge–Onkaparinga pipeline	Delivers untreated River Murray water to the urban water system. Water is discharged into the Onkaparinga Summit Reservoir and then the Onkaparinga River and other storages before diversion into the WTPs.
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 if required.
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.
Metropolitan Adelaide wastewater system	Delivers wastewater to Adelaide wastewater treatment plants (WWTPs)

More information about the pipelines transferring water from the River Murray can be found at the SA Water website.

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 P7.

Figure P7 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 the abovementioned water treatment plants can be found at the SA Water website.

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 providing water to irrigators through a large (>120 km) network of pipes	Recycled water from the Bolivar WWTP	irrigation of 20 different crops including fresh vegetables
Barossa Infrastructure Limited public company	Services the Barossa Valley providing water to irrigators through a network of approximately 189 kms of underground pipes	River Murray water is the primary water source, supplied via the Mannum–Adelaide pipeline and, if required, via the Swan Reach–Stockwell pipeline in case of need. Recycled water is received from the Nuriootpa community wastewater management scheme (CWMS).	irrigation water for viticulture
Willunga Basin Water Company reclaimed water scheme owned and operated by its users	Services the McLaren Vale region providing recycled water to irrigators through a network of approximately 120 kms of pipes	Recycled water from the Christies Beach WWTP is the primary source of water, including water injected to groundwater as part of the Aldinga Aquifer Storage and Recovery Scheme. 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.

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). Community wastewater management schemes (CWMS) 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 Wastewater Treatment Plant (WWTP)	more than 390 ML/year	irrigation of vines (Willunga Basin Water Company)	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), municipal irrigation and managed aquifer recharge through the Aldinga Aquifer Storage and Recovery Scheme	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
Nuriootpa, Lyndoch, Penrice, Mount Pleasant, Tanunda, Williamstown, Springton	700 ML/year	irrigation of vines	CWMS
Other SA WWTPs (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 website).

Stormwater harvesting (collection, treatment and use of urban runoff) is of increasing importance to the Adelaide region and forms an integral part of the South Australian Government's water security strategy (Office for Water Security 2010). 

There are currently eight stormwater harvesting and reuse projects underway in the Adelaide region, with the collective capacity to harvest approximately 8,000 ML of stormwater annually. The projects involve treating stormwater through constructed wetlands and storage in aquifers. Treated stormwater is generally used for agricultural irrigation, and irrigation of parks and ovals, as well as third-pipe supply to industrial, commercial and residential customers. For further information refer to the Department of Environment, Water and Natural Resources website.

Off-channel water storages (or farm dams) are an important water resource in the Adelaide region. The region has in excess of 15,000 off-channel water storages holding more than 39,700 ML of water when full. On average, off-channel water storages 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, water from off-channel water storages is predominantly used for irrigation purposes (Barossa Precribed Water Resources (PWRA) Water Allocation Plan: p26), whereas throughout the rest of the Adelaide region the majority of off-channel water services stock and domestic purposes (Western Mount Lofty Ranges PWRA Water Allocation Plan: p72)

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).