Abstract: The device of the present invention comprises a frame having at least one sensor mounted thereon. The sensor includes a diaphragm flush with one surface of the frame, a porous filter flush with one surface of the frame, and a strain gauge bonded to diaphragm and in electrical communication with a read-out instrument. A passageway in the frame provides communication between the filter and the diaphragm such that the water pressure of the saturated soil is transmitted through the filter such that the soil pore pressure is exerted on the back side of the diaphragm. Simultaneously, the total pressure of the saturated soil is exerted on the front side of the diaphragm when the device is embedded in the soil. The strain gauge measures the net pressure on the diaphragm which is equal to the soil effective stress, thus giving a direct measurement of such stress.