What are piezometers and slope inclinometers?

Although there are several different types of piezometers, they all do the same thing: they identify the depth of the groundwater table. They do this by measuring the static water level or the hydostatic pressure in the subsurface.

Slope inclinometers measure movement in the subsurface. There are multiple types of inclinometers, too, but the simplest kind consists of a plastic casing with orthogonal , positioned perpendicular to the movement plane you’re measuring. A trolley device is lowered to depth, and measurements are taken at regular intervals.


How do they work?

Some piezometers function as an opened standpipe, similar to a well. They are instruments that can be placed at the bottom of an open pipe with perforations or a porous base section that allows water to seep in. The water will continue to fill the pipe until it reaches the same level or pressure as the groundwater table, and can then be measured.

Another type of piezometer works using a similar hollow tube that allows water seepage. With this method, however, a deflecting diaphragm is used and, activated by the rising water level, vibrates a wire that indicates the depth of the water table.

There are variations on both types of piezometers, but these are two of the most basic (and common).

Inclinometers measure slope changes by using an accelerometer, which measures the pull and angle of the pull of gravity on a small component within the support structure (many cell phones also have accelerometers, which allow the device to detect movements like shaking or tilting). Inclinometers are installed to gather data over time, recording if the accelerometer detects the plane is gradually moving or shifting.


What are common reasons for using piezometers and slope inclinometers?

Both piezometers and slope inclinometers are standard geotech tools used for construction and infrastructure projects. They ensure public safety by providing data that allow proper engineering and monitoring of things like…

  • Landfills
  • Embankments
  • Dams
  • Tunnels
  • Ground movement and monitoring


Why choose piezometers and/or inclinometers?

For geotech and infrastructure projects, there are no viable alternatives to using piezometers and inclinometers. They are the industry standard to measuring water table levels and ground movement.




Related Resources