- GROUNDWATER:
Groundwater consists of water that in the ground rather than in rivers and streams.
Most groundwater originates as rain or as meltwater from snow and ice.
Some groundwater also comes from the overflow of streams, especially during the Spring or in times of flooding.
Smaller still are the amounts that result from biological activity, including urine and decomposition.
Groundwater is held in most soils by surface tension and by adhesion to soil particles and organic matter.
The amount of space between soil particles is called porosity. Soil with higher porosity can hold much more water than unaltered bedrock.
Many soil particles contain small electrical charges (polarity), when helps hold soil moisture in place and increase infiltration.
Infiltration refers to water that percolates into soil and is held there. Plant roots and the tunneling activities of worms and other soil creatures increase porosity.
Runoff is water that does not seep into soil, but runs along the surface directly into streams and then into ponds, lakes, and rivers.
Excess groundwater slowly seeps into local streams and rivers.
Groundwater also seeps downward into underground Aquifers, from which it can sometimes be pumped.
Water wells can also be used to draw water from underground aquifers, underground streams, and other small accumulations.
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