Piezometer

A piezometer is an unused borehole which enables the level of groundwater at a given point on the body to be measured. This level, which varies with use, provides information about the aquifer’s production capacity.

A water point can be used to find out about the resource’s quantitative status. In that case it is equipped with a piezometry measuring unit: a piezometer. This is an access point to the groundwater body (borehole, well, piezometer) via which the level of the body or the hydraulic head, using an instrument (manual probe, water level recorder, digital recorder, which may be remotely transmitted) can be measured.

In the strict sense of the term, a piezometer is a device used to measure the piezometric head at a given point on an aquifer system. This indicates the pressure at this point, enabling the measurement of the unconfined water level or a pressure reading to be recorded (G.Castany, J.Margat (1977) Dictionnaire français d’hydrogéologie).

The piezometer concept has been extended to cover all artificial (wells, boreholes, gravel pits) and natural (potholes, caves) points which provide access to groundwater.

Each piezometer is allocated a national number. This corresponds to the BSS file code linked to the BSS designation (see National Code).