Groundwater is water located beneath the ground surface that fills pore spaces of soil and fractures in rock. It is recharged from precipitation and flows through aquifers, which are underground layers of permeable materials like sand or gravel, until reaching streams, wells, or other discharge points. Pumping groundwater can lower water tables and reduce stream flows, and contaminants on the surface can pollute groundwater sources over time as the water flows through the aquifer. Lowered water tables and reduced flows can negatively impact the environment.
