water-table

water-table

The water-table is high after the heavy spring rains.

Definition
  1. Noun:
    • Underground water level: The "water-table" is the level below the Earth's surface at which the ground is fully saturated with water. It marks the upper boundary of the zone of saturation, where water fills all pores and cracks in the soil or rock.
Usage Examples
  • (The level of groundwater that determines soil moisture.)
  • (The saturated layer of soil becomes higher due to added precipitation.)
  • (The groundwater level has decreased because of excessive extraction.)
Advanced Usage
  • "to recharge the water-table": to replenish the groundwater level naturally or artificially.
    • Wetlands help recharge the water-table by allowing rainwater to slowly soak into the ground. (Wetlands restore the saturated zone.)
  • "above the water-table": refers to the unsaturated zone where soil pores contain air as well as water.
    • The root zone of most plants lies above the water-table. (The area where plant roots grow is not fully saturated.)
Variants and Related Words
  • Water-table (n): (no common variant spelling; the hyphen is often retained, though "water table" is also accepted as two words.)
  • Water-table aquifer (n): an aquifer whose upper boundary is the water-table (also called an unconfined aquifer).
    • A water-table aquifer is easily recharged by rainfall. (An aquifer with a free surface at atmospheric pressure.)
  • Perched water-table (n): a local, temporary water-table that forms above a main water-table due to an impermeable layer.
    • A perched water-table can create a small wetland in an otherwise dry area. (A small, isolated saturated zone above the main groundwater level.)
Synonyms
  • Groundwater level: the general term for the depth at which groundwater is found.
  • Phreatic surface: a technical synonym used in hydrogeology for the water-table.
  • Saturation zone boundary: descriptive term for the interface between unsaturated and saturated soil.
Related Idioms
  • "to hit the water-table": to reach the groundwater level when digging a well.
    • The well digger struck the water-table at 15 meters. (They reached the saturated zone during excavation.)
  • "below the water-table": refers to the zone of saturation.
    • The foundation of the building extends below the water-table, requiring waterproofing. (The structure is in the permanently saturated soil.)