The porous tube piezometer is a device for measuring pore water pressures primarily in a foundation though it can also be used to measure pore pressure in an embankment. It is more sensitive to foundation pressures or ground water fluctuations and is more resistant to plugging due to silting than the conventional observation well which it replaces. The porous tube piezometers may not indicate the correct pressures where sufficient flow of water into the standpipe of the piezometer is not available as in partially saturated soils. Even though the foundation pore pressure can be measured by the conventional twin tube hydraulic type foundation piezometer, there are locations not easily accessible to these piezometers, in view of the depths at which the tips are required to be installed and of the necessity of terminal facilities. This is especially true in case where the depth of water level is more than 5 m below the observation room. Every porous tube piezometer being an independent installation, the porous tube piezometer can be installed at such locations. Because of its simplicity, and reliability, the porous tube piezometer can be used by taking advantage of the drainage tunnels and grouting culverts to provide permanent access to the top of the holes. Since porous tube piezometers can be installed after completion of construction, obstruction to construction equipment can also be avoided.