What is an aquifer?

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Welcome to CoreFacts, where we're always short on time and big on science. I'm Brian Campbell. Today's question is ...

What is an aquifer?

An aquifer is a geologic formation that can store and transmit water to wells, springs and some streams. An aquifer is more like a sponge than an underground river: geologic materials have connected pores that allow water to move from one space to another, but unless the rock is fractured, water does not move through large, hollow tunnels at rapid rates. Wells can be drilled into aquifers and water can be pumped out. Precipitation adds water into the porous rock of the aquifer. This is called recharge. The rate of recharge is not the same for all aquifers, though, and that must be considered when pumping water from a well. Pumping too much water too fast draws down the water in the aquifer and might eventually cause a well to yield less water or run dry. Pumping your well too fast or too often might also cause your neighbor's well to run dry if you both are pumping from the same aquifer. Aquifers can be quite extensive, possibly stretching for tens of miles, feeding hundreds of ground water wells and streams. This is why usage of your well can influence other people miles away. More information on aquifers may be found online.

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