A simple technique which approximates the continuously disturbed line (CDL) using the relationship between water content and matric suction of compacted fine-grained soils, or apparent continuously disturbed line (CDLa) is presented. The CDL is defined as the relationship between a soils water content and suction reached by a soil specimen sheared under constant water content conditions (Croney and Coleman, in J Soil Sci 5(1):75–84, 1954). The critical state line (CSL), generated from specimens sheared under constant net normal stress, and the approximate continuously disturbed line (CDLa) appear to overlap at higher suction values. From plots of water content against matric suction, the CSL appears as a bi-linear relationship which lies below the CDLa with a shallower slope at lower matric suctions. The intersection point of the CSL and CDLa corresponds to the point where a unique value of the microstructural water content, e wm , can be back-calculated from the shear strength data. The relationship between the void ratio and the water content of compacted specimens provides an indication of the moisture content when the air entry value is reached.