Groundwater is an important part of Victoria's water supply, comprising approximately 15 per cent of the state's total water use. It is critical to creating secure water supplies to meet growing food and fibre production, for drinking water supplies and to protect environmental values.
Groundwater is the water that is beneath the earth's surface in pores and crevices of rocks and soil.
The layers of soil and rock that contain useable quantities of groundwater are called aquifers. Aquifers lie beneath all parts of Victoria.
The groundwater within the aquifers varies from drinking quality to saltier than the sea.
Groundwater and surface water are interdependent and are affected by drought and climate change. In Victoria, the millennium drought not only reduced water levels in dams and streams, it also reduced the water levels in aquifers.
Refilling of aquifers can take many years.
Like surface water, groundwater is allocated for commercial and irrigation purposes under the Water Act 1989.