enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Water table - Wikipedia

    en.wikipedia.org/wiki/Water_table

    The water table is the upper surface of the zone of saturation. The zone of saturation is where the pores and fractures of the ground are saturated with groundwater, [1] which may be fresh, saline, or brackish, depending on the locality. It can also be simply explained as the depth below which the ground is saturated.

  3. Watertable control - Wikipedia

    en.wikipedia.org/wiki/Watertable_control

    Watertable control. In geotechnical engineering, watertable control is the practice of controlling the height of the water table by drainage. Its main applications are in agricultural land (to improve the crop yield using agricultural drainage systems) and in cities to manage the extensive underground infrastructure that includes the ...

  4. Hydraulic head - Wikipedia

    en.wikipedia.org/wiki/Hydraulic_head

    Hydraulic head or piezometric head is a specific measurement of liquid pressure above a vertical datum. [1][2] It is usually measured as a liquid surface elevation, expressed in units of length, at the entrance (or bottom) of a piezometer. In an aquifer, it can be calculated from the depth to water in a piezometric well (a specialized water ...

  5. Vadose zone - Wikipedia

    en.wikipedia.org/wiki/Vadose_zone

    The vadose zone is the undersaturated portion of the subsurface that lies above the groundwater table. The soil and rock in the vadose zone are not fully saturated with water; that is, the pores within them contain air as well as water. The portion of the vadose zone that is inhabited by soil microorganism, fungi and plant roots may sometimes ...

  6. Water level - Wikipedia

    en.wikipedia.org/wiki/Water_level

    Water level, also known as gauge height or stage, is the elevation of the free surface of a sea, stream, lake or reservoir relative to a specified vertical datum. [ 1 ] See also

  7. Chart datum - Wikipedia

    en.wikipedia.org/wiki/Chart_datum

    A chart datum is the water level surface serving as origin of depths displayed on a nautical chart and for reporting and predicting tide heights. A chart datum is generally derived from some tidal phase, in which case it is also known as a tidal datum. [1] Common chart datums are lowest astronomical tide (LAT) [1] and mean lower low water (MLLW).

  8. Sea level - Wikipedia

    en.wikipedia.org/wiki/Sea_level

    Sea level. This marker indicating sea level is situated between Jerusalem and the Dead Sea. Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth 's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datum – a standardised ...

  9. Vertical datum - Wikipedia

    en.wikipedia.org/wiki/Vertical_datum

    Vertical datum. In geodesy, surveying, hydrography and navigation, vertical datum or altimetric datum is a reference coordinate surface used for vertical positions, such as the elevations of Earth-bound features (terrain, bathymetry, water level, and built structures) and altitudes of satellite orbits and in aviation.