South East Queensland
Physical information

General description

Area: 21,331 km² (provided by Seqwater)

Population: 3,178,030 (Queensland Government 2012a)

The South East Queensland (SEQ) region is located on the southeast coast of Queensland (Figure P1) and its water supply is physically defined by the following hydrological boundaries:

  • Moreton catchment, including the Pine River and Brisbane River
  • Logan Basin catchment, including the Logan River
  • Gold Coast catchment, including the Nerang River.

This region does not include Stradbroke Island, Bribie Island, the Sunshine Coast or Toowoomba.

The region is defined by the New South Wales–Queensland State border in the south, the Pacific Ocean in the east, the top of the Great Dividing Range in the west, and the headwaters of the Brisbane River in the north (Figure P2). Mountains exist along the western and southern edges of the SEQ region, while coastal plain dominates the east. The region contains several large, coastal-discharging rivers. The major catchments within the region are listed in Table P1.

 

Figure P1 Location map of the South East Queensland region within Australia
Figure P1 Location map of the South East Queensland region within Australia

 

Figure P2 Contextual map of the South East Queensland region
Figure P2 Contextual map of the South East Queensland region

 

Table P1 Major catchments within the South East Queensland region
Major catchment

Catchment area (km2)

Water resource plan area

Nerang/Gold Coast (Coomera River, Nerang River, Pimpama River, Tallebudgera Creek, and Currumbin Creek)

                                 1,367

Gold Coast
Logan/Albert (Albert River, Logan River)

                                 3,867

Logan Basin
Redlands Creek

                                     263

Bremer

                                 2,031

Moreton
Lower Brisbane

                                 1,174

Lockyer

                                 2,974

Mid Brisbane

                                     560

Upper Brisbane

                                 5,492

Stanley/Somerset

                                 1,535

Pine Rivers

                                     803

Pumicestone

                                 1,265

 Source:  The data were provided by Seqwater.

Scope of South East Queensland region water account

The SEQ region covered in this report consists of three water resources plan (WRP) areas: Gold Coast, Logan Basin, and Moreton. The total WRP area covered in this report is 21,331 km2. It is physically defined in the section above, and includes all water resources within or beneath the physical area as shown in Figure P2.

The region includes water stored in:

  • surface water storages
  • the Lockyer Valley groundwater management area (GMA) alluvial aquifer; this GMA is a part of the Clarence-Moreton, which is one of 25 management areas within the Queensland section of the Great Artesian Basin (GAB) 
  • urban infrastructure associated with SEQ water grid, off-grid local water supply schemes, wastewater systems, and recycled water systems throughout the region
  • desalinated water entering the region
  • recycled water from the Western Corridor Recycled Water Scheme.

The region report excludes:

  • water held in off-channel water storages, such as farm dams and private commercial water storages used to harvest runoff or collect rain water
  • water held in the landscape, such as soil moisture 
  • water held in wetlands that are not connected to rivers
  • water held in the GAB (except Lockyer Valley GMA), as it underlies a small portion of the SEQ region.
Population of South East Queensland region

The region is the most densely populated area of Queensland. The region's total population is approximately 3.2 million. The major cities, towns, and urban centres in the three WRPs of the region are shown in Table P2.

Table P2 Major population centres within the South East Queensland region
Locality Population
Brisbane 1,079,390
Gold Coast 536,480
Moreton Bay 389,680
Logan City 287,470
Ipswich 172,740
Redland City 144,940

Source: Queensland Government 2012a

A number of small towns are interspersed throughout the rest of the SEQ region, including Aratula, Beaudesert, Benarkin, Blackbutt, Boonah, Canungra, Esk, Fernvale, Gatton, Jimna, Kalbar, Kilcoy, Kooralbyn, Laidley, Linville, Lockyer, Lowood, Preston, Rathdowney, Somerset, Toogoolawah, Warrill View, and Yarraman.

 

Land use

Major land use activities in the South East Queensland (SEQ) region are summarised in Table P3.

Table P3 Land use in the South East Queensland region
Land use

Area (km2)

Area (% of total)

conservation and natural environments 3,303 15
grazing 11,905 56
forestry 1,558 7
dryland agriculture 236 1
irrigated agriculture 646 3
urban 2,428 11
other intensive uses 804 4
mining 3 <1
water 448 2
Total 21,331

Figure P3 shows the distribution of land use in the SEQ region. Land use activities that are major water users in the region include irrigated agriculture and urban (Department of Natural Resources and Mines 2005Department of Natural Resources, Mines and Water 2006a, 2006b; Department of Natural Resources and Water 2007).

 

Figure P3 Map of land use in the South East Queensland region
Figure P3 Map of land use in the South East Queensland region

 

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

Significant aquatic ecosystems


Wetland systems of international and national importance are located in the South East Queensland (SEQ) region. They are listed in Table P4 (Australian Government Department of the Environment 2011).

Table P4 Nationally significant wetlands in the South East Queensland region
Wetland

Area (km2)

Carbrook Wetlands Aggregation                       4
Conondale Range Aggregation

                   20

Dalrymple and Blackfellow Creeks                       9
Greenbank Army Training Area 

                   42

Karawatha Forest Park

                     3

Lake Coombabah

                  20

Moreton Bay

              2,475

Pine River and Hays Inlet

                   24

Pumicestone Passage

                   67

Upper Coomera River

                   14

Upper Pumicestone Coastal Plain

                   26

Further information can also be found on Queensland Government 2013a.

The distribution of the wetlands is shown in Figure P4. The wetlands of Moreton Bay, adjacent to the region and effected by outflows from the region, are listed in the Ramsar Convention of Wetlands (Ramsar 2013). They cover in excess of 11,000 km², most of which are on coastal islands or near shore marine areas. The habitat ranges from perched freshwater lakes and sedge swamps on the offshore sand islands, to intertidal mudflats, marshes, sandflats, and mangroves next to the bay's islands and the mainland.

 

Figure P4 Nationally important wetlands and Ramsar wetlands in the South East Queensland region
Figure P4 Nationally important wetlands and Ramsar wetlands in the South East Queensland region

 

Significant indigenous cultural places and practices

Experts are engaged each 10-year as part of formulating water resource plan (WRP) incorporating community and user interests through community reference panels. In Queensland, most of the WRPs have been finalised (Duff et al. 2011) and 'other than the limited cases where Indigenous working groups are established and cultural assessment is conducted, research indicates that there have been no mechanisms for effective Indigenous input onto the water resource plan process'.  The implementation of the recent legislative amendments in September 2013 recognised the basic rights of traditional owners to water for cultural and spiritual purposes applicable to all waters in Queensland (Australian Government National Water Commission 2013).

Landscape elements/values considered important to Indigenous communities and those have been verified with a number of other sources (Choy et al. 2011). Initially, the elements and values were combined during the research, but after discussion with the Indigenous communities it was necessary to seperate them to provide a conceptual distinction. The landscape elements used in this study  are geographical features such as rivers, lakes, mountains, valleys, and rocks, whereas the values indicate beliefs and ideals that are important to Indigenous people.

The Indigenous people emphasised four separate elements: boundaries, pathways, biodiversity matters, and important sites/areas. Within the boundaries, there are three categories: natural boundaries (including creeks, rivers, channels, mountain ranges); invented boundaries created through myth and stories for community safety (including forbidden areas and dangerous swamps, lakes, and snake habitat); and language boundaries, based on similarities or differences between dialects and language across the region.

The pathways are passages of land and water used to move through the landscapes. Usually valleys, wildlife corridors, beaches, waterways, channels, currents, and tides are recognised as pathways.

The Indigenous people spiritually believe that they are part of the landscape. They have an acute sense of even small biodiversity. In order to track the changes, they use a 'totem', a typical animal or plant species that is in some way connected to a clan group, family, or individual. This builds up a strong spiritual connection between the regional landscape and each individual. It is quoted that 'deep knowledge of the totem's spatial distribution and behaviour patterns means that the totem can serve as an indicator of the environmental changes. Hence, these various biodiversity matters which are linked to the SEQ landscape contribute to defining a spirit of place which confers particular indigenous values to those regional landscapes'.

The four key elements of boundaries, pathways, biodiversity, and important areas have great potential to be incorporated into the conventional regional planning process. 

In a study on Indigenous cultural heritage significance within the historical context of the Evandale site in the City of Gold Coast, Jabree Ltd (2013) mentioned that

'The southeast corner of Queensland contained fairly heavy concentrations of Aboriginal inhabitants prior to European settlement. It is estimated that the watershed areas alone of the Logan, Albert, Coomera, and Nerang rivers contained 1,500 to 2000, and while such estimates must be treated with caution, it is obvious from the number of 'tribes' mentioned in the various reports, that settlement was fairly dense in terms of Aboriginal populations. This would be consistent with the rich fishing grounds and the variety of game and plant life which is a feature of this area'. 

Water resources

Surface water makes up the majority of abstracted and used water resources within the South East Queensland (SEQ) region, with groundwater abstraction and use limited to various alluvial aquifers located along river valleys. Desalinated and recycled water resources within the region have been developed in recent years.

Based on the water use in relation to total inflows, available water resources and sustainable yield in the Brisbane water supply area, water resource is moderately developed (refer to Australian Government National Water Commission 2007), with surface water management plans in place across the entire region.

Groundwater resources within the region are being developed, with groundwater management areas (GMAs) now present across many high-use alluvial aquifers. It is expected that additional GMAs may be introduced as groundwater use is further developed. Agriculture and urban settlements are the main groundwater users within the SEQ region.

Water stored within surface water storages in the region is mainly for urban use and some dams provide flood mitigation facilities. As a flood mitigation measure, Wivenhoe Dam is designed to hold back 1.45 million megalitres of  additional water on the top of 1.15 million megalitres of normal storage.

Recycled water and desalinated water supplement the surface and groundwater resources for urban use and power supply.

Surface water


The main rivers in the region are the Albert, Bremer, Brisbane, and Logan. Figure P5 shows mean monthly flow volumes and rainfall for four main rivers within the South East Queensland (SEQ) region that are the Albert (Station 145102B), Bremer (Station 143107A), Brisbane (Station 143001C), and Logan (Station 145014A) rivers. Typically these rivers have flows throughout the year except Bremer; most of its flow occurs between December and June. The seasonal flow characteristics of these rivers reflect the rainfall pattern of the SEQ region, where a large proportion of rainfall occurs between December–March.

Figure P5 Mean monthly flow along the rivers and mean monthly rainfall for the South East Queensland region
Figure P5 Mean monthly flow along the rivers and mean monthly rainfall for the South East Queensland region

 

Figure P6 shows the location of flow gauging stations along these main rivers used in Figure P5.

 

Figure P6 Key flow gauging stations along the main rivers within the South East Queensland region
Figure P6 Key flow gauging stations along the main rivers within the South East Queensland region

 

Major storages

Details of major storages in the SEQ region are listed in Table P5, while the locations of these storages are shown in Figure P7.

Major storages are defined as storages with a storage capacity greater than 1,000 ML. In addition to the major storages listed in Table P5, numerous public storages with a storage capacity less than 1,000 ML exist within the SEQ region. These are not included in this account as the storage volumes could not be quantified in a way that was complete, neutral, and free from material error in accordance with Australian Water Accounting Standard 1 (Bureau of Meteorology 2012). It is estimated that these storages have a combined total storage capacity in excess of 7,000 ML which is less than 1% of total storage capacity.

Table P5 Major water storages in the South East Queensland region
Water resource plan (WRP) area

Water supply scheme (WSS)

Storage name

Total storage capacity1

Dead storage capacity2

(ML)

(ML)

Gold Coast Nerang Hinze 310,730 0
Little Nerang 6,705 0
Total Gold Coast WRP area 317,435 0
Logan Basin Logan River Bromelton Off-Stream Storage 8,210 0
Cedar Grove Weir 1,144 0
Lake Maroon 44,319 0
None3 Leslie Harrison 24,868 0
Wyaralong
102,883 0
Total Logan Basin WRP area 181,424 0
Moreton Central Brisbane River and Stanley River Mount Crosby Weir 3,430 0
Wivenhoe 1,165,238 0
Somerset 379,849 0
Central Lockyer Clarendon 24,276 0
Bill Gunn 6,947 0
Cressbrook Creek Cressbrook Creek
81,842 1,136
Perseverance 30,140 3,472
Lower Lockyer Valley Atkinson 30,400 0
Pine Valleys North Pine 214,302 0
Warrill Valley Moogerah 83,765 0
None3 Enoggera 4,567 0
Gold Creek 801 0
Lake Kurwongbah
14,370 0
Lake Manchester
26,217 0
Splityard Creek 28,700 6,400
Total Moreton WRP area 2,094,844 11,008
Total  SEQ region 2,593,703 11,008
1Total storage capacity does not include flood mitigation capacity. The volume in storage may be greater than the total storage capacity if the storage was retaining flood water or spilling at the time of measurement.

2All major surface water storages managed or owned by Seqwater have zero dead storage. Seqwater advised that due to installation of pumping systems none of their major surface water storages have any dead storage;  all water is now able to be abstracted.

3The storages are operated under additional licences within resource operations plan (ROP).

 

Figure P7 Locations of the surface water storages in the South East Queensland region
Figure P7 Locations of the surface water storages in the South East Queensland region

Groundwater

Groundwater extracted from alluvial aquifers is the primary source of water for the irrigation-dominated upland valley such as the Lockyer Valley. Groundwater use is minor in the south of the South East Queensland (SEQ) region. Occasionally, groundwater throughout the region is sourced from local confined aquifers for agricultural and domestic uses. Shallow bores are used to access groundwater for garden watering on the coastal plain.

The groundwater systems of the region can be categorised into the following types:

  • Palaeozoic age basement rocks
  • Early–Middle Triassic age metasedimentary rocks
  • Permo–Triassic age intrusive rocks
  • Mesozoic age sedimentary basins
  • Mesozoic age volcanics
  • Tertiary age sedimentary basin sediments
  • Tertiary age basalts
  • Quaternary age valley alluvial fills.

The Great Artesian Basin (GAB), one of the world's largest groundwater resources with an estimated total stored volume of 65,000 million megalitres, underlies 22% of Australia's land mass and a large portion of Queensland. The groundwater resources in the GAB in Queensland are managed under the Great Artesian Basin Plan 2006 (Queensland Government 2013b) and the Great Artesian Basin Resource Operations Plan 2007 (Department of Natural Resources and Mines 2013a). This divides the Queensland component of the GAB into 25 management areas. One of these areas, the Clarence-Moreton management area, is located partially within the SEQ region and is made up of Walloon Coal Measures, Marburg Sandstone, and Helidon Sandstone. The Clarence-Moreton management area is 400 km in length and 125 km in width and extends from Toowoomba in the west to Darr Creek in the northwest, Esk in the north, Ipswich in the east, and Rathdowney in the south (Department of Natural Resources and Mines 2013a). It underlies the Lockyer Valley, Bremer River Valley, and Teviot Brook catchment.

There are four GMAs within the SEQ region (Figure P8): Lockyer Valley, Warrill–Bremer Alluvial, Cressbrook Creek Alluvial, and Watercourse Buffer Zone (Queensland Government 2013c). These are all located within the Moreton Water Resource Plan (WRP) area. They have yet to be included in the Moreton Resource Operations Plan. A model has been developed to estimate the groundwater asset in Implementation Area 1 of the Lockyer Valley GMA. Methods for calculating groundwater assets in the other GMAs in the SEQ region are still under investigation.

Figure P8 The groundwater management areas in the South East Queensland region
Figure P8 The groundwater management areas in the South East Queensland region

Desalinated water

Desalinated water from the Gold Coast desalination plant feeds directly into the South East Queensland (SEQ) water grid. With the region's dams full or near full, the Gold Coast desalination plant has been operating in 'hot standby' mode to minimise operating costs since December 2010. Under this mode, the plant will typically produce up to 25 ML/day twice a week, with no production in between. This small amount of production is needed to keep the membranes wet and the water in the pipes fresh, while retaining the capacity to increase production to 44 ML/day (33%), 88 ML/day (66%) or 133 ML/day (100%) within 24–48 hours whenever required.

The plant may be called on if there are interruptions to supply in other parts of the SEQ water grid.

Other water resources and systems

Urban water system infrastructure

Major urban infrastructure within the South East Queensland (SEQ) region are illustrated in the Seqwater major assets maps (Seqwater 2013a).

Potable water is supplied to residents across much of the SEQ region. In the heavily populated areas around Brisbane, City of Gold Coast, Logan City, and Ipswich, potable water is supplied through the SEQ water grid. A number of SEQ residents live in communities where the drinking water supplies are not directly connected to the water grid. These communities obtain water from a range of sources including unregulated rivers, groundwater and recycled water, with varying levels of security.

The SEQ water grid was established in July 2008 to connect water supplies and treatment facilities across the region. The grid comprises an infrastructure network of treatment facilities and two-way pipes that move water between new and existing sources across the region. It provides the whole of SEQ access to more water sources, and is both dependent on climatic conditions (surface water storages) and resilient to climatic conditions (desalination and purified recycled water). The network includes about 600 kilometres of pipelines to move water from areas of surplus to areas of shortfall.

Key components include 26 major surface water storages, 51 weirs, 37 operational water treatment plants (WTP) and 14 groundwater bore fields. The roles of water retailers within the SEQ region are reported in Table  A2 in the Organisations responsible for water management section of the 'Contextual information'.

Located outside the SEQ region, Toowoomba Regional Council obtains raw water directly from surface water storages on Cressbrook and Perseverance creeks, both of which are within the region. Potable water is also supplied in times of shortage into the region from the Sunshine Coast (via the Northern Pipeline Interconnector) and Stradbroke Island (Eastern Pipeline Interconnector).

More information on the SEQ region's urban water systems can be found in the 'Urban water system' section of the 'Water resources and systems' and the Australian Water Resources Assessment (Bureau of Meteorology 2011).

Recycled water

Two main recycled water schemes exist within the SEQ region.

1 Gold Coast residential supply

Class A+ recycled water is supplied to 3,700 homes and businesses in the Pimpama–Coomera area of the City of Gold Coast for toilet flushing and external use. Industry also receives recycled water.

The recycled water treatment plant is part of the Pimpama–Coomera Waterfuture Master Plan.

2 Power station supply

The Western Corridor Recycled Water Scheme provides purified recycled water to power stations, future industrial customers and, potentially, agricultural users. It will also supplement the region's drinking water supply by supplying Wivenhoe storage when its levels fall to 40%.

The Western Corridor Recycled Water Scheme forms part of the SEQ water grid, and the power stations, namely  the Swanbank B and E power stations (located within the SEQ region) and the Tarong and Tarong North power stations (located outside the SEQ region) are the main customers for the recycled water. Treated effluent from six wastewater treatment plants (WWTPs) is further treated to purify recycled water at three separate advanced water treatment plants (AWTPs) located at Bundamba, Gibson Island, and Luggage Point.

When all three AWTPs are operating at capacity, the Western Corridor Recycled Water Scheme has a capacity of 232 ML/day subject to the availability of inflowing water from the WWTPs that supply the AWTPs.

Off-channel storages

There are approximately 1,700 off-channel storages within the region with a combined estimated storage volume of 59,000 ML.

Water resources outside region

The SEQ water grid (SEQ Water Grid Manager 2012) extends to the north and east of the National Water Account SEQ region, sourcing water from and servicing the Sunshine Coast, Bribie Island, and North Stradbroke Island. Surface water resources to the north of the SEQ region, in the Mary Basin, supply water to the SEQ water grid while North Stradbroke Island and Bribie Island supply groundwater to the grid. As the demand in these areas is less than the available supply, some of the water supplied from these three sources is transferred into the SEQ region via the SEQ water grid. This additional water is considered a water resource for the region.