Groundwater is water that is found below the earth's surface and is stored in the cracks and spaces in soil, sand and porous rocks. Most groundwater comes from rain that has infiltrated through the ground and has accumulated over many thousands of years.
Groundwater is a hidden resource that our state relies on to prosper and grow. In some areas, it is the sole water supply to many towns. Our natural environment also depends on groundwater, so we need to balance its use carefully.
What we do
The Department of Water and Environmental Regulation is responsible for managing and regulating our state's groundwater resources. We do this by allocating and licensing groundwater use.
Read more about our work:
- Water allocation planning
- Groundwater investigations
- Groundwater bores in development areas
- Rebalancing groundwater systems in response to climate change.
Groundwater in Western Australia
Soil, sand and rocks that are able to store and transmit useable quantities of groundwater are known as aquifers. Aquifers that are closest to the ground surface are called shallow or unconfined aquifers (their upper surface is the watertable).
There are also deeper, confined (sometimes called artesian) aquifers where the water is confined under pressure between impervious layers, like clay. These aquifers can be hundreds of metres thick.
In Perth we are lucky because the city is built on a multi-layered aquifer system commonly called the Gnangara groundwater system. The aquifers of the Gnangara groundwater system are part of a sedimentary basin called the Perth Basin.
Other parts of Western Australia also contain vast quantities of groundwater, which is stored in other sedimentary basins. The most important ones we use are the Carnarvon and Canning basins.
Smaller groundwater resources can also be found in fractured rock aquifers, as well as in old, buried riverbeds, called paleochannels. There are important paleochannel aquifers found throughout much of the arid zone of Western Australia, where they are often the only reliable source of water.