Artesian Springs

Hope springs – supporting artesian springs through practical property planning.

With hope springing eternal, DCQ is currently implementing a 5-year project working with land managers on improving spring condition. This Commonwealth Government funded project aims to improve property planning to ensure that the current threats to springs are reduced. Through a reduction in threats, the health of the springs will improve and be able to support the many unique species that live in them.

Artesian springs are caused by the natural releases of water from the Great Artesian Basin (GAB).  The pressure from the GAB causes water to discharge at the surface.  This can be caused by faults in the underlying rock, outcrops which cause the water to come to the surface or where the basin is very close to the surface.

The GAB is one of the largest groundwater basins in the world, covering about 22% of Australia. As the water travels across the GAB at only a few metres per year, the water when it reaches the surface can be millions of years old.   The GAB is filled or replenished at recharge sites which mainly occur in the eastern part of the basin.  These recharge areas are higher in the landscape causing the water to become pressurised in the lower parts of the basin.

The map shows the GAB within Central Australia with the recharge sites where water enters the GAB shown by the grey areas.  The dotted lines include areas where groups of springs occur.  The three main groups that exist within the DCQ region include Barcaldine, Springvale and Mulligan River.

Value of the springs.

The artesian springs are highly valued because of their outstanding natural and cultural features.  The water release in the springs has been relatively constant over thousands of years which has allowed a range of species to evolve.  These endemic species found in the springs are often found nowhere else.  These species include small fish such as the Red-Finned Blue Eye – Australia’s rarest fish, small snails and a range of plants that only grow in the artesian water. In addition, often these springs are in arid environments meaning they provide the only reliable water in the landscape and are very important for a range of other species.  Given that these species rely so heavily on artesian water and are found at a number of springs, they have been listed as Endangered under both Commonwealth and State government legislation.  The Red-Finned Blue Eye (Scaturginichthys vermeilipinnis) is only found in the Barcaldine super group – photo by Adam Kerezy.

Given that these species rely so heavily on artesian water and are found at a number of springs, they have been listed as Endangered under both Commonwealth and State government legislation.

These springs also have significant cultural heritage to Indigenous people and to current graziers. For Indigenous culture, they have been found to be intrinsically sacred and of vital importance as campsites as part of trade and communication routes (Fensham et al. 2016).  A range of artefacts are often found at spring sites and further documentation is required about the value of springs to Indigenous groups in Central Australia.

The pastoralists saw springs as key reliable water to support grazing development. Often the first roads and track follow lines of springs. Due to their value of water, often springs were drilled, drained or dug out to improve their water flow – however this often lead to their degradation and sometimes reduced their water flow (Fensham et al. 2016).  The springs also provided clues to the source of underground water, which led to experiments in bore drilling, eventually leading to the wide network of bores that support the grazing industry today.

Threats to the springs

Due to their small size and being the only water source in vast arid landscapes, the springs are subject to a range of threats. The key threat is the reduction in artesian pressure caused through the establishment of bores throughout Australia.  Since European settlement, it has been reported that 40% of discharge spring complexes in the GAB have become completely inactive (Fensham et al. 2016). However, today, this drop in bore pressure is being managed through the Great Artesian Basin Sustainability Initiative, which is working with landholders cap and pipe any free flowing bores.

High grazing pressure on springs is also a significant threat as the cattle can cause disturbance to the vegetation, changing the water quality and reducing the habitat value.  Feral animals such as pigs can also cause significant damage by changing the local topography through wallowing, disrupting the soil properties and water quality. Mosquito fish or gambusia found throughout the region is a serious pest fish that can predate the rare fish like the red-finned blue eye that live in the springs.  Weeds are also a significant threat. In some locations, weeds can drain the springs due to using the water, changing the availability of free water to be used by fish.  Weeds such as rubber vine can also smother the surrounding vegetation changing the structure of the springs.

Management of springs

DCQ is currently working with landholders to manage these threats under this project. In some instances property planning can occur to find ways to reduce impacts on springs. Actions that are currently being scoped include:

  • Improving the placement of stock waters in paddocks that contain springs to reduce grazing pressure on springs.
  • Undertake weed control in areas that are of strategic importance to springs.
  • Scope out measures to prevent exotic animal damage to springs such as feral pigs or the invasive fish species – gambusia.
  • Monitor springs following recent bore capping to determine if there are any changes to spring condition.

 

Further Information

If you would like more information on the project, contact DCQ via phone at (07) 4658 0600.

A range of publications has also been prepared on springs.  Some examples are found at the links below: