Sources
Help build the largest human-edited directory on the web.
Submit a site - Become an editor
Wikipedia. Licensed under the GNU Free Documentation License.
Are you an expert in this subject? Join the discussion and share your knowledge at Wikipedia.org.
Piezometer
From Wikipedia, the free encyclopedia
A piezometer is a small diameter water well used to measure the hydraulic head of groundwater in aquifers. Similarly, it may also be a tube or manometer used to measure the pressure of a fluid at a specific location in a column.
Piezometers should ideally have a very short screen and filter zone, so that they can represent the hydraulic head at a point in the aquifer. If the filter zone is located at a specific isolated depth, the piezometer is defined punctual, or, if the piezometer has a filter on all its length, is defined windowed. The windowed piezometer is cheaper than the punctual one, but cannot give information on vertical flows. The main problem with the piezometers is the time-lag between the variation of piezometric level in the aquifer and the respective variation in the piezometer. This time-lag is related to the piezometer (type, shape, etc.) and the soil. Modern piezometers with little time-lag are the piezometric cells, where the pressure on a membrane is measured by the pressure of gas (pneumatic piezometric cells), by vibrating thread extensimeters or by electrical extensimeters (strain gauges piezometers).
