What is a water table?

Question

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Answer 1

More info on link below:-

http://en.wikipedia.org/wiki/Water_table

Good luck!!

Answer 2

Layer of water underground.  Wells tap into the water table.

Answer 3

When I work with schoolkids, I tell them it's the level below ground where free water is encountered.  Pinecone's answer was a good one except for the thing about the water pressure being equal to atmospheric pressure.  The depth of the watertable(s) can vary quite a bit depending upon the time of year and how much rain has fallen.  

The claypan soils of Missouri have what's called a "perched" watertable.  A tight layer of clay approximately 12 inches below the surface slows or prevents the infiltration of water in wet times.  As a result, water will stand for days at a time before evaporating or infiltrating.  The permanent watertable below the clay layer varies in depth during the year and this is very evident in old hand dug wells.  In the spring the water level may be near the surface and 10 feet down in the summer and is not due to surface water entering the well.  It's quite evident that the atmospheric pressure does not vary enough to cause such fluctuations in the depth of the water table.

It's true that stagnant water tables are on a horizontal level, but whenever water is withdrawn from a well, it creates a depression in the water table in a funnel shape.  In addition, if a very large area of porous material is saturated with water coming from a higher area such as a mountain range, the water table will be higher (closer to the surface) near the mountains and increasingly deeper the farther away.

Answer 4

In simple terms it is the upper level of water in sub surface or under ground water bodies on earth.

Answer 5

The water table, or phreatic surface, is the level at which the ground water pressure is equal to atmospheric pressure. It may be conveniently visualized as the 'surface' of the ground water in a given vicinity. As water infiltrates through pore spaces in the soil, it first passes through the zone of aeration, where the soil is unsaturated. At increasing depths water fills in more spaces, until the zone of saturation is reached. This relatively horizontal plane atop this zone constitutes the 'water table'.



Cross section showing the water table varying with surface topography as well as a perched water tableA sustainable amount of water within a unit of sediment or rock, below the water table, in the phreatic zone is called an aquifer. The ability of the aquifer to store groundwater is dependent on the primary and secondary porosity and permeability.

Answer 6

water table-the upper surface of underground water ; the upper boundary of the zone of saturation. the water table rises during wet seasons and falls during dry seasons. in wet regions, the water table can be at or just beneath the soil's surface. un dry regions, such as deserts, the water table may be hundreds of meters beneath the ground.

Answer 7

The water table, or phreatic surface, is the level at which the ground water pressure is equal to atmospheric pressure. It may be conveniently visualized as the 'surface' of the ground water in a given vicinity. As water infiltrates through pore spaces in the soil, it first passes through the zone of aeration, where the soil is unsaturated. At increasing depths water fills in more spaces, until the zone of saturation is reached. This relatively horizontal plane atop this zone constitutes the 'water table'