The elevation at which the fluid pressure is equal to atmospheric pressure. The surface separating the vadose zone (where water is held under tension) from the saturated zone (where fluid pressures are greater than zero). The level to which water will rise in a well just penetrating the saturated zone.
3.4 Standpipe Piezometer
Standpipe Piezometer is used to monitor piezometric water levels. Observation wells are used to monitor ground water levels. Typical applications include: -
Monitoring pore-water pressure to determine the stability of slopes, embankments, and landfill dikes;
Monitoring the effectiveness of dewatering schemes; and
Monitoring seepage and ground water movements in embankments, landfill dikes, and dams.