Manual depth sounder: purpose
The manual depth sounder is a portable instrument used to determine the depth of wells, piezometers, and boreholes. It consists of a graduated cable wound on a manual reel, with a stainless-steel weight or metal probe attached to its end. During use, the probe is lowered into the borehole until it reaches the bottom; the depth is then read directly from the cable graduation at the reference level. The instrument does not require an electrical power supply, is easy to use in the field, and enables quick checks of borehole depth, well bottom depth, or drilling progress.