Naturally Pure New Zealand Ltd
WHAT IS AN AQUIFER?
An aquifer is a body of saturated rock through which water can easily move. Aquifers must be both permeable and porous and include such rock types as sandstone, conglomerate, fractured limestone and unconsolidated sand and gravel. Fractured volcanic rocks such as columnar basalts also make good aquifers. The rubble zones between volcanic flows are generally both porous and permeable and make excellent aquifers.
In order for a well to be productive, it must be drilled into an aquifer. Rocks such as granite and schist are generally poor aquifers because they have a very low porosity. However, if these rocks are highly fractured, they make good aquifers. A well is a hole drilled into the ground to penetrate an aquifer. Such water must be pumped to the surface. Groundwater normally flows down the slope of the water table towards the well
HOW DOES AN AQUIFER WORK?
An aquifer is filled with moving water and the amount of water in storage in the aquifer can vary from season to season and year to year. Ground water may flow through an aquifer at different rates depending on the permeability. But no matter how fast or slow, water will eventually discharge or leave an aquifer and is then replaced by new water to replenish or recharge the aquifer. Aquifers are natural filters that trap sediment and other particles (like bacteria) and provide natural purification of the ground water flowing through them.