Groundwater is the water beneath the earth's surface. It occurs in the cracks and spaces in soil, sand and rock. It is stored in and moves slowly through these geologic formations called aquifers. Managing groundwater sustainability is important to improve the quality of our waterways and ecosystems.
Groundwater is naturally replenished by rainwater that seeps beneath the land's surface. Although we can't normally see groundwater, it can be found almost everywhere under the ground.
Some groundwater facts
- Only 1% of the water on Earth is useable, and 99% of that water is groundwater.
- In Australia, groundwater makes up approximately 17% of accessible water resources and accounts for over 30% of our total water consumption.
- Groundwater in our upper catchment hinterland regions, such as Springbrook, accounts for 100% of surface water flows in creeks and rivers during dry conditions (no rainfall).
- Groundwater aquifers, like the basalt cap at Springbrook, have supported our rainforests for thousands of years.
- While groundwater volumes below ground may seem large, the sustainable use of groundwater depends on how quickly its levels restore and the properties of the aquifer.
Aquifers can contain chemicals and microorganisms that are potentially harmful.
Groundwater in urban areas can contain contaminants from a variety of sources, including industrial and vehicle fuel spillages, garden fertiliser, pesticide use, landfill leachate, seepage from sewer pipes and stormwater inflows. Pollutants in urban groundwater can include nitrates, petroleum and fuel oils, volatile organic compounds, heavy metals, pharmaceuticals, surfactants and PFAS (per- and poly-fluoroalkyl substances). Bacteria and viruses can also be found in urban groundwater.
Shallow groundwater bores and sand aquifers are particularly vulnerable.
Queensland Health advises that groundwater in urban areas is not recommended for the following domestic purposes:
- preparing food
- irrigating fruit trees, vegetable gardens, edible plants
- watering poultry where poultry or eggs will be consumed
- showering or bathing
- sprinklers for water play, or to fill swimming pools or paddling pools (due to the possibility of unintentionally drinking the water)
- consuming food products (eggs, milk, meat, fish, fruit, or vegetables) grown or produced using, or in, groundwater.
Limiting impacts on groundwater
The easiest way to limit impacts to groundwater is to avoid consumption of water-intensive products and be mindful of land use practices. There are also engineering solutions that can help. Managed aquifer recharge is the practice of putting water back into the ground to limit groundwater depletion. It can be accomplished by pumping treated stormwater or recycled water into special wells to replenish an aquifer.
Groundwater in Queensland is monitored and managed by the State Queensland Government with environmental impacts and issues considered by the Department of Environment and Science (DES).
Groundwater is regulated and you may need authorisation before you can access it.
For further information contact Queensland Government general enquiries on 13 QGOV (13 74 68).