What is the water table?

The water table refers to the upper surface of groundwater in soil or rock, where the soil or rock is still saturated with water. It represents the boundary between the unsaturated zone above (where soil and rock might contain moisture but are not fully saturated) and the saturated zone below (where all available spaces in the soil or rock are filled with water). This is an essential concept in understanding groundwater resources, as it affects various aspects of water flow, aquifer behavior, and soil moisture levels which can alter the availability of water for use, both for environmental ecosystems and for human consumption.

In contrast, the lowest point of a river pertains to surface water bodies but does not relate to groundwater levels. A collection of surface water describes lakes or ponds rather than referencing the groundwater status. A measure of soil saturation is more about the moisture content of the soil and does not specifically define the water table itself.