The pressure on the natural environment from human needs is clearly seen in the need for water. The Water Services Association of Australia report card 2009–201048 predicted residential water demand in the capital cities, based on population projections by the Australian Bureau of Statistics and projected per capita consumption. Relative to actual consumption in 2009, the estimates across all capital cities ranged from increases of 39–49% in 2026 to 64–107% in 2056. In response to both widespread drought and projected increases in demand, Australia invested $8.1 billion in capital expenditure by water utilities in 2008–09, compared with $4.5 billion in the previous year.
From 2006 to the present, several major water resource developments taking fresh water out of the environment were considered by governments around Australia, with some proceeding and some being rejected due to environmental concerns:
- In 2007, the Western Australian Government rejected the Water Corporation’s application to annually extract 45 gigalitres of groundwater from the south-west Yarragadee Aquifer, because of concerns about the potential impact on agriculture and biodiversity.
- A proposed dam on the Mary River at Traveston Crossing that would have added 70 gigalitres of supply for south-east Queensland was rejected by the Australian Government in 2009 on the basis of unacceptable impacts on the environment, including threatened species such as the Mary River turtle and the Australian lungfish.
- The Sugarloaf Pipeline was completed in 2010, connecting Melbourne’s water supply system with the Goulburn River system to deliver 75 gigalitres of water each year. This water resource was expected to result from improvements in irrigation system efficiencies of some 225 gigalitres per year, to be shared with the environment in northern Victoria (within the Murray–Darling Basin). In November 2010, the Victorian Government announced that the water resource would only be used to bring water to Melbourne during critical water shortages, due to concerns about potential impacts on regional development (including agriculture).
- A new dam wall is under construction to increase the capacity of the Cotter Reservoir, near the headwaters of the Murrumbidgee River, from 4 gigalitres to 78 gigalitres. This option to increase Canberra’s water supply was considered to have relatively minimal impact because the dam wall will be constructed in an area already affected by the existing reservoir, on land that was badly affected by the 2003 fires and previous forestry plantations.
- Tasmania is advancing plans for expanding irrigation across 13 schemes, totalling some 190 gigalitres of new water supplies, with a commitment to proceed only if the proposal is proven to be economically and environmentally sound.
- Queensland has completed the 30-gigalitre Wyaralong Dam on Teviot Brook, about 90 kilometres south-west of Brisbane, which began filling in December 2010. Before Wyaralong, the last major dam built in Australia was the Paradise Dam in central Queensland in 2005. Wyaralong is the region’s fifth largest dam and is connected to south-east Queensland’s new water grid. The grid, an interconnected network of dams, water recycling plants and the Tugun Desalination Plant, is capable of supplying 58 megalitres per day to residents.
Queensland has also introduced the Wild Rivers Act 2005. The Act aims to preserve a river that has all, or almost all, of its natural values intact by regulating new development activities that have the potential to impact on the river’s natural values. As at June 2010, nine rivers had wild river declarations: the Archer, Fraser, Gregory, Hinchinbrook, Lockhart, Morning Inlet, Settlement, Staaten and Stewart rivers. The Wenlock Basin also had a declaration, and the Cooper Creek Basin was under proposal. A declaration sets out caps on resources (including water) that can be taken in the declared wild river area, rules or limits that must be complied with when undertaking new development activities (such as quarrying, agriculture and mining) and development assessment codes that must be applied. Both agricultural and Indigenous interests, wanting further access to water for productive uses, expressed strong opposition to this program.
As part of its 50-year vision to meet water demand in the Perth region, the Water Corporation of Western Australia established Australia’s first groundwater replenishment trial for drinking water using treated wastewater at its Advanced Water Recycling Plant in November 2010. The trial recycles wastewater to drinking water standards, and can treat up to 0.5 megalitres per day before recharging it deep into the groundwater below. The current plant has the capacity to recycle 1.5 gigalitres per year; however, if a full scheme were to proceed, as much as 25–35 gigalitres per year (about 10% of current water demand) could be recycled from the Beenyup Wastewater Treatment Plant alone.
In Victoria, construction started in October 2009 on an upgrade of the Altona Treatment Plant to purify wastewater from the plant and pipe it to nearby industrial manufacturing sites, sporting clubs and councils. The plant was commissioned in April 2011 and will produce 2.5 gigalitres of class A recycled water per year, reducing the amount of wastewater discharged from the Altona Treatment Plant into Port Phillip Bay.
Most Australians live in metropolitan areas, and 2005–10 saw major transformations in how the water industry will meet future metropolitan demand. This was in response to drought, climate uncertainty, climate change, population increase and a new understanding of the need to provide water flows to the environment. The most salient features were moves towards demand management (reducing per capita water consumption) and ‘manufactured’ sources of water, such as seawater desalination and recycling, to complement historical sources of fresh water taken out of the environment. For instance, in 2004–05, Australia desalinated 231 megalitres of sea water; by 2008–09, this had grown to 33 270 megalitres.2 Desalination plants were commissioned in Sydney and at Tugun in south-east Queensland in 2010; others are under construction in Melbourne (completion 2011), Perth (completion 2011) and Adelaide (completion by 2013) (Table 4.5).
‘Water security through diversity’ has become the new dominant water management paradigm for our cities.
|Built capacity is 35% of capital city water consumption in 2008–09; the ability to increase capacity inherent in these plants is 49% of capital city water consumption in 2008–09.|
|Area||Location||Capacity (ML/year)||Ability to increase capacity (ML/year)||Completion date|
|Sydney||Kurnell||90 000||180 000||Completed|
|Melbourne||Wonthaggi||150 000||Up to 200 000||2011|
|South-east Queensland||Tugun||49 000||Completed|
|Binningup||50 000||100 000||2011|
|Adelaide||Port Stanvac||100 000||December 2012|
|Total||484 000||674 000|
|ML = megalitre
Source: Water Services Association of Australia48