piezometer for groundwater monitoring

Our vibrating wire piezometers go as deep as needed, provided the cable length is specified upfront. We’ve supplied units for boreholes over 200 meters. The key concern isn’t the sensor depth but ensuring proper saturation of the filter tip and a good grout seal at the installation level. We recommend talking to our support team about your hole diameter and water quality—saline or acidic groundwater might require a different housing material.

Once installed, a piezometer doesn’t need much hands-on maintenance. The main checks are data quality—looking for drift or sudden jumps that could indicate sensor damage or air bubbles. Every couple of years, it’s smart to perform a field calibration check if you have access, but permanently grouted piezometers usually just get compared against a nearby standpipe reading. Kingmach provides long-term zero drift specs and can advise on troubleshooting remotely if the readings go wonky.

It’s not the same unit. For standpipe installations, you’d use a much thinner probe that fits inside the pipe. Our custom piezometers come in various diameters, so you can get one that slides into a standard 50mm PVC standpipe. For fully grouted boreholes, the sensor body is thicker and often has a larger filter stone. We can build both types, but specify your installation method when ordering so we match the body geometry.

Response time depends more on the surrounding soil permeability and filter stone than the sensor. In sand, a clean filter tip will react within seconds; in tight clay, it can take hours. Our vibrating wire sensors have near-instantaneous response once the pore pressure reaches the diaphragm. If you need faster equilibration, we can supply a smaller diameter filter stone or pre-saturated tip. It’s all about matching the piezo to the ground conditions.