The Model 4675 High Sensitivity Settlement System consists of a series of vessels containing liquid level sensors interconnected by a liquid filled tube. A reference vessel is positioned at a stable bench mark location with additional vessels positioned at different locations, at approximately the same elevation. Differential settlement, or heave, between any vessel and the reference vessel results in an apparent rise or fall of the liquid level in that vessel. This system is particularly suitable for critical situations where high resolutions are required. Elevation changes of as little as ±0.02 mm are detectable.