What is an Aquifer?

What is a Groundwater Aquifer?


An aquifer is the area underground where spaces between gravel, sand, clay, or rock fill with water. Water stored underground is called groundwater.

There are different types of aquifers. When water is found in cracks and pores in the rock, we call this a ‘bedrock‘ aquifer. When water is found in the spaces between sand and gravel, we call this a ‘sand and gravel‘, or ‘unconsolidated‘ aquifer. Both types of aquifers exist in the RDN.

How a Well Works:


Further Reading:

How Over-Pumping Can Impact Neighbours & Streams:


What Makes an Aquifer Vulnerable?


Saltwater Intrusion


Interactions between Groundwater and Surface Water

Groundwater and surface water are connected. Have you ever wondered how rivers continue to flow even if there has been no rain for weeks? One answer is ground water. It continues to supply water through the banks and beds of rivers and streams. Once in the river, ground water becomes surface water! And sometimes surface water goes back into the ground.

What is Aquifer Stress?

Water use is sustainable when supply and demand are in balance. When more water is extracted than replenished, an aquifer may experience stress.  Aquifer stress compares the total demand for groundwater to the amount of natural aquifer recharge.

  • Recharge = water from precipitation and surface waters that infiltrates down to the water table and adds to water storage in the aquifer.

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