Search results
Results From The WOW.Com Content Network
A water level device showing both ends at the same height. A water level (Greek: Aλφαδολάστιχο or (υδροστάθμη) [Alfadolasticho]) is a siphon utilizing two or more parts of the liquid water surface to establish a local horizontal line or plane of reference.
A staff gauge or head gauge is calibrated scale which is used to provide a visual indication of liquid level. When installed perpendicular to an inclined or sloped surface, a staff gauge is usually calibrated so that the indicated level is the true vertical level .
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 foundations of large buildings, underground transit systems, and extensive ...
the design drain spacing (L) can be found from the equation in dependence of the drain depth (Dd) and drain radius (r). Drainage criteria One would not want the water table to be too shallow to avoid crop yield depression nor too deep to avoid drought conditions. This is a subject of drainage research.
Static level is the level of water in the well when no water is being removed from the well by pumping. [8] Water table is the upper level of the zone of saturation, an underground surface in which the soil or rock is permanently saturated with water. [9] Well yield is the volume of water per unit time that is produced by the well from pumping. [8]
The process of infiltration can continue only if there is room available for additional water at the soil surface. The available volume for additional water in the soil depends on the porosity of the soil [7] and the rate at which previously infiltrated water can move away from the surface through the soil. The maximum rate at that water can ...
The water table may vary due to seasonal changes such as precipitation and evapotranspiration.In undeveloped regions with permeable soils that receive sufficient amounts of precipitation, the water table typically slopes toward rivers that act to drain the groundwater away and release the pressure in the aquifer.
The first routine measurements of river flow in England began on the Thames and Lea in the 1880s, [2] and in Scotland on the River Garry in 1913. [3] The national gauging station network was established in its current form by the early 1970s and consists of approximately 1500 flow measurement stations supplemented by a variable number of temporary monitoring sites. [2]