dieptemeters

Dieptemeters are instruments that measure the depth of water, typically the distance from the water surface to the seabed. They are widely used in maritime navigation, diving, hydrography, and offshore operations. In English, the instruments are called depth meters, depth gauges, depth sounders, or echo sounders. The choice of name often reflects the measurement method rather than the user application.

Most modern dieptemeters fall into two broad categories: pressure-based depth meters and sonar-based depth sounders. Pressure-based devices sense the ambient hydrostatic pressure and convert it to depth using the known density of seawater and gravity. They provide real-time depth readings and are common on ships and diving gear, though accuracy depends on salinity, temperature, and local density. Sonar-based devices emit an acoustic pulse downward and measure the time it takes to return from the seabed; combining speed of sound in water with travel time yields depth. These can be single-beam or multibeam systems and are central to bathymetric mapping.

A third, traditional method is the use of a weighted line or lead line, which physically measures depth by lowering a plummet to the bottom. While largely superseded for regular use, it remains useful for quick checks or in environments where electronic systems are impractical. In operation, depth data from dieptemeters supports navigation safety, dredging and construction planning, scientific surveys, and underwater exploration.