High Quality Content by WIKIPEDIA articles! The water table is the level at which the groundwater pressure is equal to atmospheric pressure. IT may be conveniently visualized as the 'surface' of the groundwater in a given vicinity. IT usually coincides approximately with the 'phreatic surface', but can be many feet above it. 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. THe relatively horizontal plane atop this zone constitutes the water table. A 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 of the rock or soil.