Method and device for determining the nautical depth of a water mass

The invention relates to an improved method for determining the nautical depth of a water mass such as a water channel. The method characterized in that a measuring body is immersed in the fluid mass to a determined depth; the depth position of the measuring body is determined; the measuring body is set into a stationary movement at the depth position; the energy required for this movement is measured; and the nautical depth is determined from the measured movement, the energy required therefor and the depth position of the measuring body. The invention also relates to a device for performing the method.