Age 1: 1
A spring is a water resource formed when the side of a hill, a valley bottom or other
excavation intersects a flowing body of groundwater at or below the local water
table, below which the subsurface material is saturated with water. A spring is the
result of an aquifer being filled to the point that the water overflows onto the land
surface. They range in size from intermittent seeps, which flow only after much rain,
to huge pools flowing hundreds of millions of gallons daily.
Springs are not limited to the Earth's surface, though. Recently, scientists have
discovered hot springs at depths of up to 2.5 kilometers in the oceans, generally
along mid-ocean rifts (spreading ridges). The hot water (over 300 degrees Celsius)
coming from these springs is also rich in minerals and sulfur, which results in a
unique ecosystem where unusual and exotic sea life seems to thrive.
Water flow from springs
The amount of water that flows from springs depends on many factors, including the
size of the caverns within the rocks, the water pressure in the aquifer, the size of the
spring basin, and the amount of rainfall. Human activities also can influence the
volume of water that discharges from a spring-ground-water withdrawals in an area
can reduce the pressure in an aquifer, causing water levels in the aquifer system to
drop and ultimately decreasing the flow from the spring. Most people probably think
of a spring as being like a pool of water-and normally that is the case. But springs
can occur when geologic, hydrologic, or human forces cut into the underground
layers of soil and rock where water is in movement.