The Standpipe Piezometer (also known as a Casagrande Piezometer) is used to monitor piezometric water levels in vertical boreholes and offers a simple and economical method for measuring water pressures in soil and rock.
The Standpipe Piezometer typically comprises two parts: at its lowest point is a porous piezometer tip; connected to the tip is a riser pipe which continues upwards out of the top of the borehole. To measure the borehole water level, the filter tip zone is packed with sand and then backfilled above. To isolate pore water pressure at the filter tip, a bentonite seal is required between the sand filter zone and the backfill.
Alternative filter tip types may be driven or pushed into soft soil, and different tip designs are available to suit various types of ground.