groundwater

Groundwater

is also often withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells.

saturated zone

The area where water fills the aquifer is called the

Saturated Zone

this zone also known as groundwater zone is the space in which all the pores of the soil are filled with water. the water table forms its upper limit and marks a free surface.

Zone of Aeration

in this zone the soil pores are only partially saturated with water. the space between the land surface and the water table marks the extent of this zone.

Soil water Zone

zone that lies close to the ground surface in the major root band of the vegetation from which the water is lost to the atmosphere by evapotranspiration.

Capillary fringe

in this water is held by capillary action. This zone extends from the water table upwards to the limit of the capillary rise.

Intermediate zone

this lies between the soil water zone and the capillary fringe.

Aquifer

is a saturated formation of earth material which not only stores water but yields it in sufficient quantity.

Aquitard

it is a formation through which only seepage is possible and thus the yield is insignificant compared to aquifer.

Aquiclude

it is a geological formation which is essentially impermeable to the flow of water.

Aquifuge

it is a geological formation which is neither porous nor permeable. There is no interconnected rock without any fractures is an aquifuge.

water table

is the top surface of the saturated zone, where the saturated zone is not confined by overlying impermeable rocks.

Recharge

is the processes of infiltration and migration or percolation by which ground water is replaced.

Groundwater discharge

occurs where ground water flows into a stream, escapes at the surface in a spring, or otherwise exits the aquifer.

Capillary Fringe

region above water table where water rises due to capillary forces in the porous medium.

Aquifer

a geologic unit that stores and transmits water

Unconfined Aquifer

water is in contact with atmospheric pressure – drill and well hit the water table

Confined Aquifer

recharge upgradient forces water to flow down and get trapped under an aquiclude.

Porosity

Percentage volume occupied by voids. Porosity is independent of scale.

Permeability

Measures the transmission property of the media and the interconnection of the pores.

Darcy

was a French engineer who lived in the mid-16th century.

Darcy’s law

says that if permeability remains uniform, the velocity of groundwater will increase as the slope of the water table increases.

Hydraulic gradient

is the water table slope and its determined by dividing the vertical difference between the recharge and discharge points by the length if flow between these points.

Hydraulic head

the vertical difference between the recharge and discharge points.

Cone of depression

is a circular lowering of the water table immediately around the well in an unconfined aquifer.

Salt water intrusion

is another problem arising from groundwater use in coastal regions

Filling in wetlands

is a common way to provide more land for construction.

karst

distinctive terrain known as

Well

is a hole drilled into the ground to access water contained in an aquifer.

Bored wells

are usually bored into an unconfined water source, generally found at depths of 100 feet or less.

Consolidated well

are drilled into a formation consisting entirely of a natural rock formation that contains no soil and does not collapse. Their average depth is about 250 feet.

Unconsolidated or sand wells

are drilled into a formation consisting of soil, sand, gravel or clay material that collapses upon itself.