From the early 1900s water that came to the surface under natural pressure (artesian water) from bores in the Great Artesian Basin was allowed to flow uncontrolled into open drains and creeks for watering stock. However, even in well-maintained drains, up to 95 per cent of this water was wasted through evaporation and seepage.
Beginning in the 1950s regulation required that all new bores be fitted with headworks to control flows, and each of the States started programs to upgrade and control bores and to convert bore drains to piped delivery systems. However, inadequate technology to deal with hot, high pressure water along with a lack of commitment from governments and landholders meant that by the late 1990s more than 1,500 artesian bores continued to flow into more than 34,000 km of open bore drains.
Such uncontrolled flow of water from bores into open earth bore drains threatened the maintenance of pressure required to support important groundwater dependant ecosystems and the continued access to artesian water by pastoralists. The use of open bore drains also encouraged feral animals and weeds, and contributed to other land management problems such as salinisation and erosion.
Prior to 1999 a number of programs (initiatives of both government and private landholders) were commissioned to address the uncontrolled flow of water from artesian bores. These programs resulted in more than 650 flowing bores being controlled and 3,500 km of bore drains eliminated. This saved more than 126,000 Ml/yr of water and helped to restore artesian pressure. From a Basin-wide perspective these rehabilitation programs were uncoordinated and underinvested.
The Great Artesian Basin Sustainability Initiative
A basin-wide coordinated approach to bore rehabilitation was proposed as part of the Great Artesian Basin Strategic Management Plan in 2000. This resulted in the development of the Great Artesian Basin Sustainability Initiative (GABSI). Under GABSI and over a fifteen-year period, the State and Australian Governments and landholders agreed to work cooperatively and to invest significant public and private funds to repair uncontrolled artesian GAB bores and replace open bore drains with piped water reticulation systems.
GABSI entered its fourth three-year phase in October 2014 and continues to be delivered through state agencies. A decade of successful implementation has resulted in some remarkable outcomes. More than 450 flowing bores have been rehabilitated and more than 15000 km of bore drains eliminated. GABSI has installed more than 23,000 km of piping, tanks and troughs to deliver water to stock. This has resulted in returning 165,000 million litres of water back to the environment every year and continues to assist the recovery of artesian pressure in the Basin.
Over fifteen years GABSI will result in more than $350 million being invested in water infrastructure renewal. In Phase 1 of the program (1999-2004) the Australian Government provided almost $32 million of funding which was matched by State governments, and landholder contributions. In Phase 2 (2004-2009) Australian Government funding was $42.7 million (again matched by the State, and with landholder contribution). For Phase 3 of the program (2009-2014), the Australian Government commitment is now $85 million.
Controlled bores with closed water delivery systems enable landholders to harvest artesian pressure to distribute water to stock around their property without the need for costly pumping. Pastoralists have found stock water delivered through tanks and troughs enables them to control the location and delivery of water. This makes stock management and the management of total grazing pressure easier, increasing productivity and positive environment outcomes.
Importantly, the recovery of artesian pressure that results from controlling flowing bores and closing bore drains protects the range of values associated with Basin, including the ecological values of springs, the social and economic benefits supported by the Basin, and the Basin’s indigenous cultural values.
Great Artesian Basin Coordinating Committee Secretariat
Water Division, Department of Agriculture and Water Resources
GPO Box 858
Canberra ACT 2601
Phone 1800 900 090